LNG Tank Operations Manual

LNG  Vehicle Fuel Tank System

Liquid Natural Gas — The Clean Fuel for Today and Tomorrow 

OPERATIONS

MANUAL 

 A Chart Industries Company 

SAFETY Hazards of LNG

 A Chart Industries Company 

Vehicle Tank Customer Se Service:

Phone hone:: 77 7700-72 7200-6 -677 7700 Fax: 770-479-6539

Fuel Station Customer Se Service:

Phone hone:: 95 9522-8 -882 82--52 5204 04 Fax: 952-882-5080

Web site: www.nexgenfueling.com This manual dea d eals ls with wi th LNG vehicular fuel tanks, the hazards, hazards, and the safety pr eca ecauti utions ons that th at are neces nec essa sary ry w hen working with this type of equipment. The manual is designed to familiarize experienced mechanics and vehicle operators wi th the features, safety safety precautions, operating procedures and m aintenance of the th e LNG Fuel Fuel System provided by NexGen Fueling. For more generalizedd inform generalize inf ormation ation on o n LNG fuel systems systems refer to NFPA NFPA 57 and 59A available from the National Nation al Fire Protection Assoc Association, iation, ww w.nfpa.org, 617617770-30 770 -3000. 00. For inform in form ation on handli handling ng cryogenic cryog enic liquid liq uidss Refer Refer to CGA P-12 P-12 available from fr om the Compressed Gas Association, www.cganet.com, 703-788-2700. No attempt attempt should be made to fill or m ainta aintain in this equipment until this manual and its supplements have been been read and fully u nderstood. Throughout this manual items appearing in Bold Text highlight conditions that can result in serious injury or death.

Table of Contents Section

I II III IV V VI VII VIII IX X

1

Description

LNG is predominately m ethane gas. gas. ItIt is cooled to very low temperatures (less (less than m inus 200° F) and stored stor ed as a cryogenic liquid liqu id under un der pressure pressure (up to 230 psig). psig). Working wi th the equipm ent can can expose you to the follow ing hazards. hazards. Flammable Gas : Although the liquid is not flamm able it

rapidly evaporates in air into i nto large vol um umes es of gas. The The gas expands expands to 600 tim es its original orig inal liquid li quid volum v olum e. So even small liqu liquid id leak leakss can can pose p ose a large fire haz h azard ard near the leak. The gas is flammable in concentrations of between betw een 5% and and 15% in air. ai r. Cryogenic Temperatures :

The liquid LNG is below minus mi nus 200 200° F. Since this liquid is stored under pressure you can be cryogeni cryogeni ca cally lly b urned very easily easily b y coming in i n contact wi th a pressurized pressurized liquid liqu id stream. You You can also be cryogenically cryogenically burned by hard contact contact w ith a cryogenic temperature fuel line. Large Expansion Ratio :

Since S ince LNG wil l expand to 600 times its original volume when w armed from a cryogenic liquid to a room temperature gas it will build extremely high pressures (over 3000 psig) if trapped in lines. lin es. Press ressures ures this high w ill caus causee lines and fittin gs to fail. Care Care must be taken taken in the design of pi pin pingg systems and durin g maintenance main tenance operations to assure assure that liquid ca cannot nnot bec become ome trapped t rapped between two valves valves.. Althoug h natural gas is non-toxic it is an inert Inert Gas : Although gas and and can cause cause asphyx asphyxiatio iationn if prese pr esent nt in very v ery large concentrations. conce ntrations. This is a minim min imal al hazard hazard with w ith vehicle v ehicle fuel systems sys tems as they they simply simp ly don’t don ’t contain enough product prod uct to displace large large quantities of oxygen o xygen around the vehicle.

Page No.

Saf et y In t r o d u ct i o n Pl u m b i n g Co m p o n en t s A ccesso r i es In st al l at i o n Fu el i n g Tr o u b l esh o o t i n g Co m po po n en t Rep l acem en en t Par t s Li st A p p en d i x W ar r an t y

1 2 3 -4 5-6 7 -1 0 1 1 -1 2 1 3 -1 6 1 7 -1 8 1 9 -2 1 2 2 -2 5 26

Safety Precautions

Keep the equipment Keep equipm ent area well ventilated. This This will w ill prevent the buildup bui ldup of methane m ethane gas if leaks are are present. present. Cover eyes and exposed skin skin when w hen working w orking on LNG systems. Isolate the fuel tank and and rem ove the pressure from t he system sys tem prior p rior to m aintena aintenance nce operations. operations. Keep equipment away from open flames, sparks, and temperatures over Ò 1200° F. 1200 Utilize Util ize leak detection equi pm pment ent to locate lo cate small leak l eaks. s.

INTRODUCTION Congratulations !!

You have just purchased the worl ds most advanced LNG vehicle fuel tank. Despite its high tech appearance you will find it easy to use and maintain. It will give years of trou ble free service and is designed to outlive the vehicles on wh ich it is installed. Cryogenics

The LNG fuel tank is a cryogenic container. This means that it stores the natural gas fuel as a highly refrigerated liquid at low pressure. Typically the fuel temperature is about –220°F, and the fuel pressure is about 70 psig. The reason for cryogenic storage is that natural gas is much more dense as a low temperature liquid than it is as a compressed gas. Typically you can get three times as much gas in the same space at about half the weight if it is stored as a cryogenic liquid instead of as a compressed gas. The Storage Tank

To contain thi s cryogenic fuel with out the use of any outside source of refrigeration the tank has to be extremely well insulated. To achieve the high level of insulation efficiency needed the LNG pressure vessel is covered w ith i nsulation and enclosed by an outer vacuum vessel. A vacuum is pulled betw een the LNG tank and the outer shell. This combinati on of insulation and vacuum, called super-insulation, has the highest thermal efficiency known with an R value exceeding 5000. This type of insulation allows for standby times of over a week with no loss of product.

I

Both the in ner pressure vessel and the outer v acuum vessel are constructed o f stainless steel. Stainless has both the lo w temperature strength necessary to contain the cryogenic fuel and the hig h temperature toughness to allow the vacuum casing to armor the inn er pressure vessel. With an all stainl ess vessel support structure as well, the LNG fuel tank can withstand years of vehicular service with no loss of performance. Fuel Delivery System

The driving force for delivery of the fuel to the engine is provi ded by the fuel pr essure itself, there are no pumps in the system. When the engine demands fuel the pressurized liquid natural gas flow s out of the tank toward the engine. The cold pressurized fuel then passes through a Heat  Exchanger . The Heat Exchanger  uses engine coolant to vaporize the liquid and turn it into a gas. Once out o f the Heat Exchanger the fuel is a warm gas, at tank pressure, ready t o be bu rned by the engine. Tank pressure is maintained by a tank mounted Pressure Control Regulator  that vents excess pressure into the fuel li ne during periods of engine operation.

Super Insulation Inner Vessel Evacuation Port

Relief Valves Vapor Shutoff  Valve

Pressure Control Regulator 

Outer Vacuum Jacket

Excess Flow Valve

Fill Check Valve Fuel Shutoff Valve

2

II PLUMBING COMPONENTS 1 Fill Check Valve

3 Excess Flow Valve

The fill l ine check valve is a bronze swing check with a soft seat. Its function is to prevent backflow through the fill li ne in the event of a fuel coupler failure or vehicle accident. It relies on tank pressure to seal and despite the soft seat should not be regarded as a positive shutoff valve. The Fill Check Valve connects to a top fill line inside of the tank.

The Excess Flow Valve i s a specialized check valve with a hard metal seat designed to cut off fu el flow if it exceeds a certain lim it. Its function is to pr otect the fuel line between the tank and Heat Exchanger against uncontrolled fuel release in the event of a vehicle accident. It is not designed to protect piping downstream of the Heat Exchanger , this is the function of the Auto-  matic Fuel Shutoff Valve . The Excess Flow Valve is not a positive shuto ff valve. Its hard seat allow s a small flow to pass by to allow the valve to automatically reset when the Fuel Shutoff Valve is closed.

2 Fuel Shutoff Valve

The Fuel Shutoff Valve (Liquid Valve) is a bronze globe valve with a soft seat. Its function is to provide a positive shutoff of the fuel line for service and maintenance operations. The fuel shutoff valve connects to the liquid withdrawal line at the bottom of the tank and to the vapor withdrawal line at the top of the tank through the Pres-  sure Control Regulator . The fuel shutoff valve is open for normal vehicle operation.

4 Vapor Shutoff Valve

The Vapor Shutoff Valve (Vent Valve) is a bronze globe valve with a soft seat. Its function is to provide a positive shutoff of the vapor withdrawal line for service and maintenance operations. The valve connects to the vapor withdrawal line at the top of the tank. The Vapor Shutoff Valve is closed for normal vehicle operation.

Shrouded Tank (Truck Style)

Headring Tank (Bus Style) 8

8 12

10 2

6

3

2

6 7

7

1

4 5

3

3

1

4 5

PLUMBING COMPONENTS II 7 Secondary Relief Valve

5 Pressure Control Regulator

The Pressure Contro l Regulator (Econom izer) is a bronze pressure reducing v alve that is op en at pressures above its setpoint and closed at pressures below its setpoint. Its function is to allow vapor to flow into the fuel line during vehicle operation to reduce the tank pressure to i ts setpoint. It is assisted in its operation by an Internal Check Valve in the fuel pickup line provi ding a 2 psi bias pressure to aide vapor flow. The setpoint of the regulator is nonadjustable being set at the time of m anufacture. Flow throug h the regulator is not directional, it will be an open valve w henever the fuel line pr essure is above its setpoint.

The Secondary Relief Valve is a brass cryogenic relief valve set at 1.5 tim es the maxim um allowable working pressure of the tank. Its function is to vent product to atmosphere to prevent a catastrophic failure of the tank in the event of a malfunction of the Primary Relief Valve  or line. It is connected to the vapor wi thdrawal line provi ding a secondary relief path to th e tank. It is protected from debris by a red vinyl cap and should never be piped away. Since this is the last line of d efense for the tank if the red vinyl

6 Primary Relief Valve

Evacuation Port

The Prim ary Relief Valve is a brass cryogeni c relief valve set at the maximum allowable working pressure (MAWP) of the tank. Its function i s to vent pro duct to atmosphere if the tank pressure exceeds the MAWP. It is connected to the top fill line thereby providing additional safety against over pressurizing the tank during filling operations. The Prim ary Relief Valve is equipped with a pipeaway adapter to permit piping the vent gasses to a safe location on the vehicle.

The Evacuation Port is located on the non-plum bing head of the tank. Its functio n is to pro vid e a re-sealable connection for evacuating the tank. Its secondary function is to prov ide a pressure relief path in the event of a produ ct leak in the vacuum space. Do not remove the plug, not only will it cause the tank to lose vacuum, but it w ill void yo ur warranty as well.

cap is ever missing the vehicle should be immediately removed from service and the primary relief system inspected.

LNG Piping Schematic 9 Gas To Engine

11

13

Top Fill Line

Vapor Line

6

7

To Vent Stack

3

10

12

2 14

1

4 5

8 Fuel Pickup Line

4

III ACCESSORIES 8 Fuel Contents Gage

Each LNG fuel tank com es equi pped w ith an electronic Fuel Contents Gage. The gage consists of two parts: the fuel gage sender and a dash m ount f uel gage. The fuel gage sender com es mount ed to the fuel tank. Its function is to convert the electronic signal from the internal fuel level probe to a signal compatible wi th the dash mount gage. It is a solid state, sealed unit and no field adjustments are possible. The sender accurately reflects the actual m ass of the product in the tank and is unaffected by produ ct state, pressure or temperature. It is designed to dampen the effects of acceleration, braking, cornering and hi lls, although some variation wil l be seen on the gage under these transient conditions, similar to its gasoline or diesel counterpart. The fuel gage is a standard autom otive typ e gage calibrated to the sender. It reads out empty to full and has an accuracy of ± 1/16th of a tank. Note: The gage, the sender and the cable connecting t he sender to th e fuel tank are calibrated as a system and must be replaced with identical parts to maintain gage accuracy.

9

Heat Exchanger

Every LNG fuel system m ust contain a Heat Exchanger. The function of the Heat Exchanger is to v aporize the cryogenic liquid fuel and deliver it as a warm g as to the engine. The Heat Exchanger is mou nted in the fuel line near the LNG tank. It gets its heat from the engine cooling system and connects to the engines water jacket through flexible coolant lines. Note: The Heat Exchanger do es not affect the f uel pressure it sim ply raises its temperature and turns the fuel from a liquid into a gas. 5

10

Fill Fitting

Every fuel system must contain a cryogenic fill connection. The function of the fill connection is to provide a connecting point to the re-fueling station that permits a cryogenic pressure transfer to occur. The Fill Fitting incorporates a positive shutoff d evice to prevent fuel leakage when disconnected. Each fuel connection needs to be moun ted to th e vehicle at a location capable of w ithstanding a 250 pound load. This is necessary to assure that in the event o f a dri veaway the breakaway devices on the fuel station will fail first. Each fuel fitting shou ld be fitted w ith a dust cap to prevent the introduction of water or debris into the fuel tank. 11

Automatic Fuel Shutoff Valve

Every LNG fuel system m ust contain an Autom atic Fuel Shutoff Valve. Its function is to shut off the fuel flow to the engine when the ignition is switched off or when activated by an out of limits sensor. Its recommended mo unting location is at the warm g as outlet of the Heat Exchanger , this enables a wide selection of valves to be used. If a cryogenic valve is used it can be mounted directly to the liquid shutoff valve in place of the Excess Flow Valve , this configuration is not recommended as it requires the use of a relief valve in the fuel line.

ACCESSORIES III 12

Tank Pressure Gage

Standard on shrouded tanks, an optional mechanical pressure gage can be mounted to any LNG fuel tank. A 1/4” pip e size pressure gage port is located on th e Primary Relief Valve  tee at the 12 o’clock position on the plumbing m anifold to allow for direct or remote mounting of a Tank Pressure Gage. 13

Overpressure Regulator

Some natural gas engines are unable to accept pressures up to the MAWP of the fuel tank. The fuel systems on these engines needs to be equipp ed with an Overpressure Regulator to keep the operating pressure window within acceptable limits for the engine. The Overpressure Regulator i s mo unted i n engine fuel line downstream of the Heat Exchanger  and Automatic Shutoff Valve . It works in conjunction with the Pressure Control Regulator on the fuel tank to establish the fuel systems operating pressure window. The Pressure Control Regulator on the tank is set to th e norm al operating pressure of the engine. The Overpressure Regulator in th e fuel line is set to the maximum operating pressure of the engine. The settings on these two regulators assure that the engine will always see pressures within its operating range. Note: If an Overpressure Regulator is used it m ust be set at least 25 psig above the Pres-  sure Control Regulator on the tank to avoid transient low pressure spikes on acceleration.

14

Vent Connector

Some refueling stations either require or have provision for venting the tank during re-fueling. Vehicles operating at these stations should b e equipped wi th Vent Connectors compatible with the fuel stations design. The Vent Connector is piped to the Vapor  Shutoff Valve on the LNG tank. By connecting the station to the Vent Connector and opening the Vapor  Shutoff Valve  th e tank pressure can be vented to its desired l ocation at the fuel station. Note: Depending on the design of the Vent Connector and vehicle piping a relief valve may be necessary in t he vent line to prevent liq uid fro m becomin g trapped between the Vapor Shutoff Valve  and the Vent Connector.

6

IV INSTALLATION – Materials Many materials are unaffected by cryogenic tem peratures. In general 300 series stainl ess steel, copper and brass, alum inum , fiberglass, wood, polyethylene, polypropylene, teflon and epoxies can be safely used. Carbon steel, 400 series stainless steel, zinc, PVC, and rubber become brittle at low tem peratures and wil l fail if flexed while cold. When running low temperature piping care should be taken in its mounti ng to stand it off of the vehicle frame, electrical wiring, and brake or air lines that can embrittle and fail. Some paints, notably enamels, tend to de-bond and flake off at cryogenic temperatures. Piping

All piping material must be able to withstand the effects of low temperatures without failure. On fuel lines that carry LNG liquid we recomm end the use of rigid 300 series stainless steel tubing. Fill and fill crossover lines may be rigid o r flexible m etallic or non-metallic tu bing rated for cryogenic service. Vent and relief pipeaway li nes may be constructed out of flexible tubing or hose suitable for natural gas service. Since liquid and v ent lines repeatedly go from ambient to cryogenic temperature allow ances for thermal expansion must be designed into the piping system. This is typically accomplished by incorporating S bends or expansion l oops into ri gid l ines. In general if one end of the tube can be mov ed 1/2" by hand while the other end is fixed it i s flexible enough for low temperature service. If the tube is ri gid it m ust be redesigned since it wi ll m ove when it gets cold easily pulling itself from supports and fittings. Tube Fittings

Rigid t ube fitting s should be either a double ferrule type (Parker A-lok, Swagelok, or equivalent) or 3 piece 37°flare type (Parker Triple Lock or equ ivalent). Tubing wall thicknesses used should be per fitting manufacturers specification for gas service. Pipe Threads

All pipe fittings should be installed using thread sealants. After the sealant is applied to the fitting it should only be tightened in the clockwise direction to its final position. If the fitting is tightened past its desired position do not turn it counterclockwise to reposition. Remove the fitting clean both surfaces and start over. Turning a pipe thread counterclockwise will cause 7

tiny thread leaks to develop over tim e. If multiple pipe fitting s are stacked up be sure to use two w renches to keep the back fitting from breaking loose. There are many types of commercial pipe fittings available. Nexgen recomm ends the use of NPTF fitti ngs for leak resistance. When stainless fittings are used we recommend the use of stainless to brass fittings to prevent galling during installation. When maintenance is performed replace the brass fittings wi th new. The use of stainless to stainless pipe threads is not recommended as severe galling during installation makes achieving leak tight fittings nearly impossible. If maintenance is required it is difficult, if not imp ossible, to get the fittings apart w ithout destroying the threads. If stainless to stainless threads must be used be sure to use a pipe sealant with anti galling compounds incorporated into it. Pipe Sealants

For small threads (less than 1/2” pipe size) anaerobic sealants li ke Loctite 569 are recom mend ed. For f ittings 1/2” pipe size and over use an anaerobic sealant with a teflon lubricant such as Loctite PST 567. When using anaerobi c sealants on stainless steel the fitt ing must first be prim ed with an activator for th e sealant to cure. A typical activator is Loctite Kleen-N-Prim e. All anaerobic sealants have a cure tim e before pressure can be applied, the primers shorten these tim es. PST on brass requires 3 days to cure (4 hours prim ered), 567 requires 1 day (30 minutes primered). When applying anaerobic sealants apply a small amount to the male thread 2 threads up from the end. Do not allow the sealant to run into the piping system as it will seal up valves and regulators as well as fittings. The use of thread tapes is not recomm ended as tape filaments from maintenance operations can interfere with regulators, relief valves, and engine components. Pipe Support

Piping and tubing should be supported along its length to gu ard against vibrati on. A general guideline is one support per tw o feet of tubing. A practical test is to “ strum” the installed tube by hand. If it vibrates it is not supp orted w ell enough. Stainless P clamps, and polyethylene or polypropylene tube clamps are commonly used on cold lines. Care must be taken in support placement to allow fo r thermal expansion and contraction of the lines.

INSTALLATION – Components IV Vehicle Tank

Since the fuel pickup is located near the plumbing head the vehicle tank should be installed with the plum bing head of the tank facing the rear of the vehicle. Rear facing mounting assures that at low fuel levels that the fuel pickup wil l remain submerged during acceleration or w hen climbing hills. The tank should be secured to the chassis wi th tw o steel straps located just inb oard of the head to shell welds. The straps should incorporate rubber p ads to prevent rotation o r slippage of th e installed tank. In accordance wi th NFPA 57 guid elines the mo unti ng system should be sufficiently strong to hold 8 times the full weight of the tank.

The Heat Exchanger shoul d be piped so that the LNG inlet and the coolant i nlet are on the same side. It can be m ounted either vertically o r ho rizontally. To pr event air from becomi ng trapped in the coolant side of the Heat Exchanger the coolant ports must be pointed up in hori zontal m ounts, the gas out and coolant out ports must be up on vertical mounts. Note: The if the Heat Exchanger is installed in series with the cab heater the coolant piping must allow coolant to flow even when the cab heater is turned off. Automatic Fuel Shutoff Valve 11

To m inim ize the flow restriction to the engine the Autom atic Fuel Shutoff Valve should have a mini mu m Cv of 2.0. It should b e mount ed to the warm gas outlet of the Heat Exchanger . Even tho ugh t he valve is screwed directly into th e Heat Exchanger its weight should be supported by a mounti ng bracket. The valve should close when the vehicles igni tion switch is placed in the off p osition. It also may be activated by out of li mi ts sensors on the engine or fuel system. Nexgen recomm ends the inclusion of a low t emperature limit swit ch on the warm gas line to protect the valve and dow nstream compon ents in the event of a cooling system m alfunction.

Heat Exchanger 9

To assure proper Excess Flow Valve function the Heat Exchanger should be m ounted w ithin 8 feet of the tank. The LNG inlet to the Heat Exchanger is pi ped to the tank using rigid 300 series stainless steel tubing. If the Heat Exchanger is less than 3 feet from the tank 3/8” od x .035 wall tub ing can be used. If greater than 3 feet 1/2” od x .049 wall tubing is used. The recom mended coolant flow to the Heat Exchanger is 1 gallon per m inute of 180 F° coolant per 50 horsepower engine output. For coolant l ines less than 10 feet in length this flowrate can be achieved using 5/8” heater hose. For runs longer than 10 feet use 3/4” heater hose.

8

IV INSTALLATION – Components Primary Relief Valve Vent Stack

Engine Fuel Line

The Primary Relief Valve should b e piped to a safe point on the vehicle. Since methane gas rises it is typically piped to a vent stack that exhausts at the top of the vehicle with fl ow directed upw ards. Since there is a possibility of relieving liquid through this line its discharge path should be away from persons, igni tion sources or materials that could be damaged by exposure to cryog enic temperatures. To prevent t he possibility o f water accumulating and freezing in the relief valve line the vent stack should include pro visions for excluding rain and wash water from the line and incorporate a low point w ater drain. The min imum recomm ended size for vent stack is 1/2” tubing.

The fuel line from the Automatic Shutoff Valve to the engine can be either metallic or n on-metallic tubing suitable for natural gas service. If non metallic tubing is used a low temperature shutoff switch must be incorporated into the fuel system. The engine fuel line should be, at a minim um, 1/8" larger in diameter than the LNG liquid line into the Heat Exchanger to prevent a flow restriction as the fuel expands when it is vaporized.

The tubing connecting the Primary Relief Valve  pipeaway to the vent stack can be either m etallic or non-metallic tubing suitable for low temperature methane service. The minim um tubing size is 1/2” . Fill Line

Many vehicles have remote moun ted fill connections and require a fill line to connect to the fuel tank. Since the fill lin e is handling hi gh pressure, high flow cryogenic liquid NexGen recomm ends metallic tubin g be used. The minim um fill line size depends on the tank size and fill connector, but it generally would be 1/2” tubing for tanks less than 50 gallons and 3/4” tubing for tanks larger than 50 gallons. If rigid tu bing is used it should i ncorporate at least one S bend betw een the fill connector and the fuel tank to allow for flexibility and collapsibility in the event of a vehicle accident.

9

Fuel Contents Gage 8

The Fuel Contents Gage consists of tw o part s: the sender and the gage. The sender is a sealed unit that comes mo unted to t he fuel tank. It is connected to the vehicle vi a a 3 pin female Weatherpak connector. The pins are power (red) A, signal (green) B, and grou nd (bl ack) C. The sender shoul d be pr otected wi th a 1 amp fast blow automotiv e type fuse. The gage is a standard automotive type fuel gage and should be mo unted on the dashboard inside of the vehicle. The power, signal and g round wi res shoul d be common to the sender for proper gage function. Gage Wiring Schematic

Gage +

S -

1A

Pin A Red

Sender 

Pin B Green

12 V Pin C Black

INSTALLATION – Multiple Tanks IV When available space on th e vehicle won ’t accom modate the vehicles fuel requirement i n a single tank it is easy to manifold multiple tanks together. The fill, liqu id, vent , relief valve, and gage lines are simpl y connected in parallel in accordance with the foll owing recommendations. The tanks will fill and supply product independently of one another, but act as a system, appearing to the engine as a single large tank. Note: During refueling it is comm on for the tanks to go full at different ti mes. This causes the flow and pressure to change several tim es during m ultiple tank fills. The multiple pressure spikes can confuse the automatic shutoff system in some fuel stations into shutting down before all of the tanks are completely fill ed. Therefore NexGen does not recomm end mu ltiple tank systems of m ore than thr ee tanks per vehicle.

Relief Valve Lines

The Primary Relief Valve  discharge lines may be piped together into a single vent stack. 1/2” minimum tubing should be used. Vapor Shutoff Valves

The Vapor Shutoff Valves (Vent Valves) can b e piped to a common connection, but they must have Check Valves  15 placed in series with them only allowi ng flow out of th e tanks. This will prevent depressurizing the system if the vent valves are accidentally left open du ring vehicle operation. Fuel Contents Gage 8

The Fuel Contents Gage can be configured to have one gage read out the multiple tanks contents as if it were a single tank. In this configuration a capacitance cable is run between the tanks and the sender simply sums the tanks contents and displays them on a single gage. The connecting cable is p art of the gage calibration and m ust be replaced with an identical part if damaged to assure proper gage operation. Alternatively each tank can have its own sender and display its contents on a separate gage. Note: On m ulti ple tank systems the tanks fill and drain i ndependently from one another. It is unusual, except after a fill, for all of the tanks to have the same liquid level. While it is interesting to watch it has no effect on engine operation, range or system re-fueling.

Fill Crossover Line

The fill l ine size requirem ent is the same as a single tank systems. To achieve reasonable fill tim es use 3/4” (min) line size for tanks whose aggregate capacity exceeds 50 gallons, 1/2” (min) line size can be used on tanks w hose aggregate capacity i s less than 50 gallons. On grou ps of tanks that are mounted side by side a fill m anifol d is generally the easiest solution to m ultiple tank fill lines. Fuel Line

The fuel lines to the engine are simply teed together before they enter the Heat Exchanger . Line sizes are the same as in single tank installations to assure proper Excess Flow Valve function. No te: Since the fuel lines are comm on to all of the tanks the fuel pressure will be the same in all tanks except im mediately after filling.

11

13

9

Dual Tank Schematic

Gas To Engine To Vent  Stack

Top Fill Line

Vapor Line

6

7

6

7 3

3 2

2 15

10

12

12 14

Top Fill Line

Vapor Line

1

4

15

1

4 5

5

Fuel Pickup Line

8

Fuel Pickup Line

10

V FUELING Fuel Station Requirements

Vent Filling

Your LNG fuel tank is designed to be fi lled fro m any LNG fuel source. The only requirements on the station are filtration and delivery pressure. Since LNG, like any liquid fuel, can pick up and transport debris that can cause fuel system problems a 100 micron or finer fuel filter is m andatory on all fuel station fill lines. The LNG fuel tank has a 230 psig Primary Relief  Valve on its inl et line therefore the delivery pressure of the fuel statio n should be 225 psig or less.

Although the preferred method of fueling is via a single hose top fill it is possible to vent fill the tank. This procedure is usually used w hen pressure transferring fuel out of a temporary fueling facility or portable fuel tank. Since this normally is a manual procedure it requires more operator knowl edge of the system. If the product is vented to atmosphere it should be directed to a vent stack discharging to a safe location. The vehicle tank must be vented slow ly if i t is above its normal operating pressure so that liquid isn’t drawn out of the Pressure Control Regulator into the vent gas stream. Care must also be taken to monitor vehicle tank pressure during a fill so th at at the end of the fill it arrives at its normal operating pressure.

Normal Fueling

The LNG fuel tank is designed to be top filled through a single fill hose with no vent return. This is accomplished by spraying subcooled LNG into the vapor space of the tank. The cold liquid condenses the vapor and creates space for itself inside of the tank eliminating the need to vent product. Since this will result in a 100% fill a small tank (ullage tank) inside of the m ain tank guards against overfilling. A typical fill sequence would involve connecting the fill hose to the tanks fill coupler. Open the stations fill valve and m onitor the flow or line pressure as the fill progresses. Initially at the start of the fill there is a brief pressure spike as the fill piping cools down. The flow and pressure then remain stable duri ng the remainder of the fil l. When the tank becom es full the pressure rapidly spikes up to the station’s delivery pressure and the flow rate falls off dramatically. The reason the flow doesn’t immediately go to zero is because of the ullage tank. The ullage tank has a small opening (relative to the main f ill l ine). Once the main tank goes full there will still be a small flow (typically 1-2 gpm) into the ullage tank. When the rapid pr essure rise or flow drop is observed the tank is full and th e station fill valve should be shut. Even though it is still possible to put more liquid into the tank by continuing to fill the ullage tank, the ullage tank is there to allow for fuel expansion and standby tim e. If the ullage tank is completely filled the hold tim e will be zero and the Primary  Relief Valve will open almost imm ediately after the fill. If the fill is stopped at the onset of the rapid pressure rise/ flow d ecay, when the ull age tank is emp ty, the tank will have about a week of standby time even if the vehicle isn’t driven. Most permanent fuel stations automatically monitor and perform these functions so the fueler’s only duty is to connect and disconnect the fuel hose and push the Start button. 11

Vent Filling from a Station with a P/B

When Vent Filli ng fro m fu el station w ith a pressure building system the LNG in the station should be saturated to w ithin 10 psig of the vehicle tanks Pressure  Control Regulator setting (vehicle operating pressure). The fuel station sho uld be pressurized to at least 50 psig above the vehicle operating pressure. The vehicle fuel tank’s pressure should be vented to 20 psig below the vehicle operating pressure. Connect the fil l li ne from the station. Open the station’s fill valve and the vehicles Vapor Shutoff Valve . Once liquid starts flow -

FUELING V ing into the vehicle tank close the Vapor Shutoff Valve . Filling should no w proceed much like a single hose fill. Once the flow stops or the pressure on the vehicle tank rapidly rises shut off the station’s fill valve. Confirm the tank is full using the Fuel Contents Gage on the dash. If the filling tank lo ses pressure before the vehicle tank is completely fil led, vent the vehicle tank pressure dow n, this time only to the vehicle operating pressure, allow the filling tank to re-pressurize and repeat the process. Vent Filling from a High Saturation Source

If the fuel station’s saturation pressure is above the vehicle operating pressure and the station has no pressure building system a vent fill should be performed as follows. Vent the vehicle tank down to 30 psig below the vehicle tanks Pressure Control Regulator setting (vehicle operating pressure). Connect the fil l line from the station. Open the station’s fill valve and the vehicles Vapor Shutoff Valve . Throttle the vehicle tank’s Vapor  Shutoff Valve (and station’s fill valve if necessary) during the fill to maintain the vehicle tank pressure between 10 and 20 psig below the vehicle operating pressure during the fill. When the tank reaches 3/4 full, close the Vapor Shutoff Valve and continue filling until the pressures equalize and flow stops.

Fueling a Warm Tank

An LNG fuel tank that has been idle for a long period of ti m e, still has fuel, and is at its reli ef valve pressure is considered to be a warm tank. This tank must be vented dow n below the fuel station delivery pressure prior to filli ng. First Fill or Hot Tank Fill

An LNG tank when first installed is considered to be a hot tank. Hot tanks will build pressure rapidly during the fill as the pressure vessel cools dow n, on m any stations this w ill prematurely stop the fill . The recomm ended first fill pro cedure is to put 5-10 gallons of LNG into the tank. Check the plumbing for leaks. Drive the vehicle for 10–15 minutes, this wil l pul l the pressure dow n to norm al and cool dow n the tank. Recheck for leaks and fill norm ally. This same procedure is recommended for tanks that have been empty and out of service for m ore than ten days. Alternatively put 5-10 gallons of LNG into the tank and fuel l ike a warm tank.

12

VI TROUBLESHOOTING – Components Rapid Pressure Rise

There are three main causes of rapid pressure rise on LNG fuel systems. They are overfilling, fuel system leaks or malfunctions and loss of vacuum . A properly functionin g, properly filled LNG fuel system should build less than 15 psig per day. Any system that builds more than 40 psig per day needs troubleshooting to discover the cause. Overfilling 

If the fuel tank is overfilled there wi ll be little or no space for the fuel to expand as it picks up heat through the insulation. The most common cause of overfillin g is not shutting off a single hose fill at the onset of th e rapid pressure rise at the end o f a fill. (See Fueling Section) Fuel System Leaks 

Since LNG has such a large expansion r atio piping leaks can cause pressure rise if th ey draw l iqu id into the external li nes. If the vehicle has not been operated for a few hours (and the outside temperature is above freezing) all external plum bing lines should thaw out. If a line remains frozen troubleshoot the pipin g to determine the cause. Vacuum Loss 

Total loss of vacuum is an unusual event for an LNG tank (resulting i n frosting of the entire ou ter shell), however the vacuum w ill slow ly decay wi th tim e as gasses diffuse out o f the tank materials. This will show up over time as more and more rapid pressure rise times, eventually exceeding 40 psi/day. Once the vacuum has decayed to this point the tank wi ll n eed to be re-evacuated by a competent maintenance facility. While the rate of decay varies with tank service conditions (higher pressure tanks vacuum decays faster) the vacuum life should exceed the engin e life of the vehicle. It is recomm ended that at engine overhaul or replacement that the fuel tank be re-evacuated. Pressure Rise Test

To establish the pressure rise of an LNG fuel system the follow ing test should be performed. Fill the tank to betw een 1/2 and 3/4 full. Drive the vehicle for about 10 minutes. Park the vehicle. After 15 m inutes record the tank pressure. After a prescribed period of ti me 13

(at least 8 hour s) record the pressure again. Check to see that the plumb ing is thawed, if so this is the pressure rise for the fuel system. Fuel Contents Gaging System

Problems w ith the fuel contents gauging system can be easily diagn osed by th e use of the Fuel System Tester (P/N 11656419). The tester enabl es diagnosis of both tank side and vehicle side problems wit h the gage circuit. The Fuel System Tester p lug s into the Weatherpak connector between the fuel gage sender and vehicle wi ring h arness. It gets it’s power from the vehicle itself. To use the tester sim ply connect the Weatherpak plugs, turn on the pow er to the gage circuit and read the li ghts on t he front p anel. If the gage circuit is functioning prop erly all three green lights will be lit and the fuel gage wi ll read 1/4 full. Fault condit ions on the fuel tank or wi th the vehicle wiring will be displayed on the tester. If an intermittent probl em is present wiggle the wiring connectors with the tester connected, an open or shorted connector wil l cause the fault li ghts to flash. The fuel tank can be tested off of the vehicle. Simply connect the tester to the Weatherpak connector on the tank and push the test button o n the top of the unit. On mul ti tank systems both tanks need to be connected since the connecting cable is an active part of the circuit.

Debris in Components

Debris comm only enters the tank in tw o ways. It is carried into the tank during refueling, from eith er dirty fill connectors or u nfiltered fuel, or parts that aren’t properly cleaned prior to reassembly duri ng m aintenance operations. Either way the end result is the same, the debris becomes lodged in a tank comp onent and interferes with its function. Debris In Relief Valves 

Debris in the Primary Relief Valve  will typically lodge underneath the valve seat and cause the

TROUBLESHOOTING – Components VI relief valve to remain open w ell below its 230 psig setpoint. More commonly the cause of a relief valve staying open is water fill ing t he discharge piping due to inadequate shields and drains on the pipeaway line. If a relief valve is stuck open due to water contaminatio n it can be quickly thawed by pourin g w ater on the outside of the valve. If the valve reseats when thawed th e pipeaway drains and shields should be inspected. If the valve do es not reseat w hen thawed it will have to be replaced. If the Primary Relief Valve becomes plugged wi th debris the tanks pressure could ri se above 230 psig up to the Secondary Relief Valve  setting of 350 psig. If tank pressures of over 250 psig are observed or if the red vinyl cap is gone from the Secondary Relief Valve  the vehicle should be immediately removed from service and the Prima-  ry Relief Valve  and pipeaway lines inspected to

Pressure Control Regulator Test Procedure

The Pressure Contr ol Regulator and Internal Check  Valve  can be checked for proper function without removing them from the tank utilizing the followi ng procedure. Vent the tank pressure to at l east 25 psig belo w the Pressure Control Regulator regulator setting. This in all cases should be less than 100 psig. Note: It is recomm ended, but not imp erative, to empty the LNG from the tank for this test. Connect a nitrogen gas cylinder w ith an adjustable non-relieving pressure regulator (0-150 psig) and a 0-100 scfh flowmeter rated for at least 150 psig (Dwyer VFB-53 or eq.) to the ou tlet of the Excess Flow  Valve on the cylinder. Minimum line sizes should be 1/4" to maintain adequate flow for the test. Do not use

determine the cause of failure.

air for this test. This will result in a flammable (explosive) gas mixture inside the tank.

Debris in Pressure Control Regulator 

Open th e Fuel Shutoff Valve on the tank. Adjust the nitrogen gas pressure until it is slightly (~5 psig) above the tank pressure and nitr ogen gas begins to flow into t he tank. The flow should be in the 10-20 scfh range. If the flow pegs the meter either the Pres-  sure Control Regulator is fully op en or the internal check is open, generally the sound will reveal which.

Typically debris in the Pressure Control Regulator  (Economizer) wil l lodg e underneath the regulator seat holdin g the valve open b elow its setpoint. If this happens the tank wi ll graduall y lose pressure during operation. It can be diagnosed by observing the regulator on the vehicle when it comes in from its route. If the tank pressure is more than 10 psig below the Pressure Control Regulator setpoint, the tank still has fuel, and the regulator is frosted over it i s stuck open du e to debris. The first course of action to fi x the problem w ould be to take the vehicle out of service and allow the fuel to warm and its pressure to rise to at least 30 psig above the Pres-  sure Control Regulator setting. This will f ully open the valve and allow th e debris to be carried out into the fuel stream wi th use. Also since the debris may be ice it wil l have tim e to melt and correct itself. If the problem does not correct itself wi th use the regulator wi ll have to be replaced. On tanks that are heavily contaminated it is possible to completely plug the Pressure Control Regulator  with debris. In this case the tanks pressure will rise in service and the regulator w ill not be frosted over during use even though th e tank pressure is above it’s setpoint. The regulator will have to be replaced to correct this problem.

Slow ly in crease the pressure, opening the Pressure  Control Regulator , until the flow rapidly increases to the 60-80 scfh range. Decrease the pressure observing the flowm eter as you do. The point at which the flow stops rapidly fallin g w ith decreasing pressure is the Pressure  Control Regulator setting. Never exceed 150 psig du ring this test or you could rupture the flowmeter.

Close the Fuel Shutoff Valve before you remove the test equipm ent. Pressure Control Regulator Test Nitrogen

14

VII TROUBLESHOOTING – Leaks While none of us w ant leaks in our equipm ent any pressurized system w ith removable parts is subject to their development. Preventative maintenance activities on LNG fuel systems should include a program t o detect and repair leaks. Other than the economic impact of losing fuel, the primary hazard of leaking natural gas is a flamm ability hazard. If the lo cal gas concentration reaches 5% in air the gas mi xture wi ll be flamm able. In order to reach this concentration the natural gas must leak out faster than it can diffuse into the surrou nding air. This means that large leaks are more hazardous than are small leaks and th at the hazards and m aintenance program can be classified by leak size. Liquid Leaks

Liquid leaks are by defini tion hazardous. Even small ones release hundreds of times more gas than do gaseous leaks through the same size opening. They are always flammable. All liquid leaks should be im m ediately repaired. They are the easiest type of leak to detect since they are both visible and audibl e requiring no specialized equipm ent to find. The principal cause of liq uid leaks are parts failures or po or installation techniques. Loose or cracked fittings and worn valve packings would be typical examples. Gaseous Leaks

Gaseous leaks are by nature less hazardous than liquid leaks since they release less natural gas than liquid leaks. The difficulty in dealing with small gaseous leaks is that they are invisible, and require special techniques and equipment to locate. Audible Leaks

Gaseous leaks becom e audible, in a quiet envi ronment, at a flow rate of about 1 liter per m inute (1000 cc/min). Audible leaks are large leaks and alw ays flammable. These leaks should be im mediately repaired. They are caused, like their liquid counterparts, by loose or cracked fitti ngs, worn valve packings and failed seals. Inaudible Leaks

Although all audible leaks are flammable it is not true that all inaudible leaks are not. Because they are inaudible and invisible leak detection equipment must

15

be used to locate leaks smaller than 1 liter per minute. Most inaudible leaks are not the result of parts failures, but rather are the result of i mp roper assembly techniques or small defects in parts. Leaks that spiral through a pi pe thread, follow porosity through a casting, or seep past a particle trapped in a compression fitting are typical examples. These leaks typically don ’t grow larger with age and will generally show up in the first few hours of vehicle operation. Ultrasonic Leaks

Even though w e can’t hear leaks much smaller that 1 liter / minute they are still m aking sound. The sound is in the ultrasonic frequency range and can be “ heard” by the use of an ultrasonic leak detector. An ultrasonic leak detector will rapidly find and pinpoint leaks down to about 100 cc/min. Ultrasonic size leaks, while flammable, pose little threat to moving vehicles or to m aintenance f a ci l i t i e s. T he main threat would be accumulation of g as in a poorly ventilated compartment while the vehicle is parked. They should be repaired when discovered. Small Leaks (Bubble Testing)

Leaks small er than 100 cc/min .are most easily pi npointed via commercially available bubble test solutions. It should be noted that thi s is not soap. Mo st soaps contain high levels of chlorine and surfactants. While it is true that soap solutions will find the leaks, like bubbl e test solutions, it is also true that they w ill cause leaks by breaking dow n sealants and corroding fittings. Bubble testing w ill not o nly pinpoint the source of small leaks, but it wi ll also classify them by size. One caution on the use of bubb le test solution s, leaks larger than 100 cc/min blow out th e bub bles so fast and dry th emselves out so quickly that they mi ght be mi ssed in a piping check relying only on bubble testing. It is recommended that general leak surveys be done with an ultrasonic leak detector or flamm able gas detector then pinpo int small leaks with bubble test solutions.

TROUBLESHOOTING – Leaks VII Small Flammable Leaks

Insignificant Leaks (Diffusion)

Leaks between 25 cc/min and 100 cc/min are flammabl e in still air. If ignit ed the flame ranges in size from less than 1/16th of an inch tall, sustainable only in dead calm condi tions to a flame the size of a normal cigarette lighter flame. This size of leak is characterized by bu bbles that grow and burst at the site of the leak before they can flow away from it. These leaks pose no hazard in mo ving air, or in well ventilated compartments, but could accumulate inside of sm all, poorl y venti lated enclosed spaces. These leaks are typically caused by poor piping design or support that puts cyclic strain on the joints.

Leaks smaller th an 1/2 cc/mi n. are so small and di ffuse so rapidly that they can be ignored. They are characterized by a series of uniform size tiny (smaller than a pinhead) bubbles that emerge from the leak. This might show up im mediately as a chain of ti ny bubbles on leaks near the 1/2 cc/min size or appear as foam around the fitting up to 5 minutes after the fitting is sprayed with bubble test solution fo r the smallest ones. In either case the leaks are not flam mable and will not accumul ate inside of vehicle compartments.

Non Flammable Leaks

Leaks smaller than 25 cc/mi n. are not fl amm able in air. They are characterized by a stream of bubbles that grow in size and foam o ff of th e leak. Typically the bubbl es range in size from 1/8” to 3/8” in diam eter. The bubbles don’t burst at the site of t he leak, rather they flow away from the leak and burst downstream as they dry out. In a ventilated environment, even in still air they pose no flamm ability hazard and are mainly an economic nuisance. The largest leak in this group, 25 cc/min., will cost about $5.00 per year in lost product.

Flammable Gas Detectors

Handheld flammable gas detectors are available in a wide variety of configurations and sensitivities. The sensitive ones are good at detecting the presence of mi nute quantities of flamm able substances, but are difficult to use to pinpoint the source. The less sensitive ones can more easily pinpoint leaks, but have to be held qui te close and are difficult to use around mo st vehicle plumbi ng. They are useful for surveying for leaks, but not goo d at identifyi ng the sources.

16

VII COMPONENT REPLACEMENT Tank Mounted Components

Prior to starting any wo rk on tank mo unted plum bing com ponents that cannot be isolated by closing the Liquid Shutoff Valve or Vapor Shutoff Valve . De-fuel the tank. Release all pressure from the fuel tank. Do not leave the tank open to air any lon ger than it takes to replace the defective part. Piping Components

For plumbing com ponents that can be isolated from the tank by closing the Liquid Shutoff Valve or Vapor  Shutoff Valve . Close the liqu id and Vapor Shutoff Valve s. Release all pressure from the plum bing line under maintenance.

is stamp ed on the data plate located on the plum bing end of each tank. Do not replace a relief valve with a higher pressure one. Do not attempt to repair or reset a relief valve. Product Isolation Valves

The Liquid and Vapor Shutoff Valves have spring loaded valve packings. This automatically compensates for therm al shrinkage and w ear. If a valve packing does become damaged or wear out the valve stem assembly can be replaced as follows:

Bonnet Assembly Copper  Gasket

General

Fully open the Shut-off valve

When removing components use a backup wrench on pipe fittings so as not to disturb downstream plumbing.

Loosen and remo ve the Bonnet Assembly. (The whole assembly should u nscrew out of the valve body.)

Clean all tr aces of p ipe sealants from pipe th reads, this will require the use of a stainless steel wire brush. On female threads the sealant residue must be blow n out of the fitting with nitrogen gas, this may require purging out the entire tank with nitrogen gas. Do not use shop air to purge out LNG tanks this can result in a flamm able (explosive) gas mi xture inside of the tank. Air also intro duces large quantities of water into the tank which can freeze and plug lines. Replace brass pipe fit ting s with new, don’t attempt to reuse the old fittin gs. Stainless steel pipe fittings must be primed with activator prior to the use of thread sealant. Allow sufficient time for the thread sealants to cure before pressure testing the piping. Pressure test the plum bing after all new parts installations and re-check after a days service.

Remove the old Copper Gasket and discard. Adjust the valve seat on the new Bonnet Assembly until no threads can be seen protrudin g from the bonnet. Place the new Copper Gasket onto the replacement Bonnet Assembly. Note: Due to the horizontal alignment o f the valve, care must be taken to properly align the Copper Gasket between the Bonnet and Body. The gasket should protrude evenly from all sides of the bonnet’s wrench fl ats. Thread in the new Bonnet Assembly and tighten it hand-tight. (It may be necessary to screw in the Bonnet Assembly until it almost touches the Copper Gasket and then align the gasket with the groove before hand-tightening the Bonnet Assembly.

Pressure Relief Valves

Tighten the Bonnet 1/8th turn fro m hand tight (~25 ft-lbf)

The inner pr essure vessel used in an LNG fuel tank is designed and rated for a m aximum operating pressure. The maximum operating p ressure for the vessel

If the valve leaks, tighten the Bonnet another 1/16th turn until leak stops.

17

COMPONENT REPLACEMENT VII Pressure Control Regulator Replacement

Since the Pressure Control Regulator regulator is mou nted in the in verted position care must be taken during its installation to prevent thread sealant from flow ing into and plugging the valve seat. To install the regulator first thread it two threads onto the stainless pipe nipple on the tank. Apply a drop of thread sealant onto the joint and continue tightening norm ally. Internal Check Valve Replacement

The internal check valve is located inside of the plum bing m anifold on the tank, behind the elbow connecting the manifol d to the economizer U tube. The tank must be empty and purged w ith nit rogen gas prior to startin g thi s procedure. To remo ve the check valve remo ve the economi zer U-tube and the elbow in the manifold. Insert the check valve wrench into the valve and unscrew. Flow nitrogen gas at ~20 scfm through the tank and clean out the internal 1/8" pipe thread with a 7/16" diameter stainless steel wire brush. Clean the pipe coupling on the manifold w ith a 5/8" diameter stainless steel wire brush. Primer both the internal thread and the 1/4" pipe coupling on the manifold with activator for the thread sealant using a fine brush applicator. Install a new check valve using the check valve wrench. Install a new elbow, taking care to stop at the proper ori entation to m ate with the econom izer U-tube. Re-install the U tube. BNC Connector Replacement

to the BNC connector. Push the w ire into the connector m aking sure it engages the internal pi n by about 3/8" after making contact with it. Once engaged it should easily rotate on t he pin. Screw the BNC connector into the elbow. Put a 4" piece of encapsulating heat shrink over the sender wi re and connect the BNC halves together. Heat the heat shrink until it uniformly shrinks onto th e fitting and the encapsulating liner m elts. Extra care mu st be taken to assure that the back side of the heat shrink gets heated and no voids, or lumps are present. Fuel Gage Sender Replacement

This is a non-pressure component and can be replaced without de-pressurizing the tank, however before using a heat gun around the plum bing shut off the product isolation valves and check for leaks. Follow instructio ns for BNC Connector Replacement to disconnect the BNC cable. Inspect the BNC connector on the tank for corrosion and fo r the presence of the garter band around the female contacts. Unlatch and pull apart the Weatherpak connector. Remove the mounting clips and pry off the old sender. Scrape off remnants of the VHB tape adhesive. Peel off the backing f rom the VHB adhesive on the new sender and place it on its mounti ng plate. Install the m ounting clips with the hooks onto the plastic box and the smoo th side on the stainless plate. Reconnect the Weatherpak conn ector. Conn ect the BNC cable per the instructions for BNC Connector Replacement.

This is the most diffi cult part on th e tank to replace since it has both pressure and electrical components in it. The tank must be empty and d epressurized prior to starting this procedure. To remove the connector put a longitudinal cut in the encapsulating BNC heat shrink tub ing encasing it. Connector  Heat the heat shrink w ith a heat gun to cause it to split away from the fitting. Grab one end of Garter  Band P/N 11657737 the still hot tube with a pliers and peel it from the connector. Heat Disconnect and inspect the male Shrink connector and sender wire for Tube P/N 11502575 damage or corrosion. Unscrew the BNC connector from the elbow. Pull the wire out of the fitting. Clean the thread sealant out of the mating elbow with a w ire brush. Prim er the replacement BNC connector with activator for the thread sealant. Make sure the garter band is installed around the female contact inside of the BNC connector. Apply thread sealant 18

VIII PARTS LIST 3 8

Headring Tank (Bus Style) 6

16

19

17 18

2

7

20

1

17

21

4 8

22 5

Item No.

Part No.

1

11556768 11556733 11673278 11556741

2 3

10614840 4

5 6 7

8

11673251 9715759 11055541 10524262 11208974 11209011 10645662 11718341 11718309 10923888 10484900 11718552 10692071 10692101 11055867

19

Description Fi ll Ch eck Val ve 1/2" (Tan ks > 50 g al lo ns) Fill Check Valve 3/8" (Tanks < 50 gallons) Fu el Sh ut of f Val ve Reb ui ld Ki t (Red Han dl e) Excess Fl ow Val ve 3/8" Bro nze (Headring Tank) Excess Flow Valve 3/8" Stainless (Shrouded Tank) Vap or Shutoff Val ve Rebui ld Kit (Silver Handle) Rego Valve Rebuild Kit (Obsolete) Pr essu re Co nt ro l Reg ul at or (Eco no mi zer ) Internal Check Valve 2 psi Pri mary Rel ief Val ve (230 psi ) Seco ndary Reli ef Val ve (350 psi ) Red Vi ny l Cap Fuel Gage Sender 12 Volt Singl e Tank 30" Lead Fuel Gage Sender 12 Volt Dual Tank 30" Lead Fuel Contents Gage 12 Volt (Dash Mount 2-1/16") BNC Connector Kit (Obsolete) New BNC Connector Kit Sender Mounting Clip Stainless Male Weatherpak Kit Fuel Gage Sender 12 Volts 15" Lead (Obsolete)

Item No.

Part No.

9

10682851 9722999 10668725 11488232 10492678 10797447 11019170 10557574

10

11 12 13 14 15 16 17 18 19 20 21 22

10798239 10624239 10924101 10644942 10586834 11674262 11548178 11666414 11359158 1211102 11708178 1210402 11646202 11502559 1111632

Description Heat Exch ang er 150 Horsep ow er Heat Exchanger 300 Horsepower Heat Exchanger 450 Horsepower Fill Fitting (Parker) Dustcap (Parker) Fill Fitting (JC Carter) Dustcap (JC Carter) Fill Fitting & Dustcap Tanks < 50 Gallons (NexGen) A ut om at ic Fu el Sh ut of f Val ve 12 Vo lt 3/8" Tan k Pressu re Gag e 300 p si 1/8"

Bushing 1/4" Male X 1/8" Female Ov er pr essu re Reg ul at or 30-100 p si (Red ) Overpressure Regulator 100-200 psi (Brown) Ven t Co nnecto r an d Dustcap (45 Flare Elbow 3/8") Vent Check Valve 3/8" Tee 1/4" Brass Street Elbow 1/4" Brass Plug 1/4" Brass Hex Nipple 3/8" Stainless Elbow 1/4" Brass U Tub e Assem bly 37°Flare Copper U Tube Assembly Stainless (Obsolete) 37°Flare Elbow 1/4" Brass

PARTS LIST VIII

29

Shrouded Tank (Truck Style)

8

30

28 27

25

31

26

3 32 28

12 33

10

34 37 36

38 35

Item No.

Part No.

25

11658975 2913921 2914071 2811726 2710131 1013356 1111602 10888656 10502004 10790982 11647862 11672742 10923765 11384505 2913701 2914071

26 27 28 29 30 31 32 33a 33b 33c

Description Sen der M ou nt in g Br acket Stai nl ess Bolt 1/4-20 X 1-1/2" Stainless Lock Nut 1/4-20 Stainless Tube 1/2" OD Nylon Tube 3/8" OD Stainless Elbow 1/2" OD X 3/8" Male Nylon 37°Fl are Connector 3/8" Brass Bu lkh ead Co nn ect or 3/8" Br ass Co mp ressi on El bo w 3/8" St ai nl ess 45°Street El bow 3/8" Brass Cover Plate Stainless - Single Tank Cover Plate Stainless - Dual Tank Cover Plate Stainless - Blank Grom met Bolt 1/4-20 X 1/2" Stainless Locknut 1/4-20 Stainless

Item No.

Part No.

34 35a 35b 36a 36b 37 38 39

11377751 11647846 11649227 11377823 11658596 11377778 11647871 10928902 10746359 11015144

Description 37°Flare Elbow 3/4" Brass Fill Tube Sub Assembly (Driver) Fill Tube Sub Assembly (Passenger) 37° Fl ar e El bo w 1/2" Br ass 37°Flare Elbow 1/2" Stainless - Dual Tank 37°Flare Elbow 3/8" Brass Vent Tube Sub Assembly BNC Patch Cord 3' BNC Patch Cord 8' BNC Patch Cord 10'

20

VIII PARTS LIST Shrouded Tank Configurations 25

25 33a

34 34

36a 36a 35b

35a

Driver Single

Passenger Single 25

25 33b

34

34 36a

35a

36b

35a

36b 35b

35b

Driver Dual

Passenger Dual 25 33b 33c

33c

36a 36a 39 35b

21

36a

35a

Driver Dual

Passenger Dual

Remote Fill/ No Sender

Remote Fill

APPENDIX – Connections IX

Relief Valve Connection - 3/8" FPT

7 Liquid Connection - 3/8" FPT

3

Vent Valve - 3/8" FPT

4

1

8

Fill Connection - 3/8" FPT (below 50 gallons) Fill Connection - 1/2" FPT (above 50 gallons)

3 Pin Female Connector Housing Weatherpak 12015793

Liquid Connection - 3/8" FPT 30 30

Relief Valve Connection - 3/8" FPT 30

Fuel Filling Connector

Vent Connection - 3/8" FPT

10

22

IX APPENDIX – Connections Heat Exchanger Part No.

9

Horsepower Rating

A

B

C

D

E

150 300 450

11-1/4 19-1/4 27-1/4

4-1/2 4-1/2 5

5-1/2 14-3/4 21-1/2

7-1/2 15-3/4 22-1/2

4-5/8 4-5/8 5-1/2

10682851 9722999 10668725

D

Coolant In (1/2'' FPT) LNG In (3/8'' FPT)

C (  Ma    x  ) 

Coolant Out (1/2'' FPT)

Specifications:

Max. Operating Pressure (LNG): 300 p.s.i.g. Max. Coolant Pressure: 50 p.s.i.g.

Gas Out (3/8'' FPT)

A

B

Automatic Fuel Shut Off Valve 11

Contents Gage 8 1/4" x .032 Spade Connector Light

2 Pin Female Connector Housing Weatherpak 12015792

Ground 3/8" FPT

+12 VDC

Overpressure Regulator 13

Gage Signal (Green)

Vent Check Valve 15 3/8" MPT

Ignition (+12 VDC)

Ground

3/8" FPT 1/2" FPT 1/4" FPT

3 Pin Female Connector Housing Weather Pack 12010717

Vent Connectors 14 3/4-16 x 45° Flare 3/8" MPT

3 Pin Male Connector Housing Weather Pack 12015793

Vehicle Half 

23

Sender Half 

APPENDIX – Labels IX

LNG 230 PSI Max – P/N 10647617: This label must be mounted in plain sight near the fill connector. It is the most impor tant label from

a safety standpo int since it noti fies the fuel station o perator of the pressure lim it o f the vehicle tank.

LNG (Diamond) – P/N 10586412: Place these l abels on

the right rear and left front of the vehicle. It identifies the vehicle as an alternative fueled vehicle, that runs on LNG.

Data Plate: Permanently

affixed to the tank this label gives the model number, serial number, date of manufacture, volumetric capacity and w orking p ressure inform ation about the tank. It also i dentifies the manufacturer and pl ant wh ere built.

METHANE

REFRIGERATED LIQUID DANGER: CRYOGENIC LIQUID AND GAS UNDER PRESSURE. CAN FORM FLAMMABLE MIXTURES WITH AIR. MAY CAUSE RAPID SUFFOCATION. MAY CAUSE ANESTHETIC EFFECTS. MAY CAUSE FROSTBITE. WARNING: SECURE ALL CYLINDERS WHILE IN STORAGE AND IN USE.

label i denti fies the LNG by it s HAZMAT identification number. Although not required, many safety, and emergency response org anizations u se this number to identify hazards and formulate suitable responses to accident situations.

Keep away from heat, flame and sparks. Store and use with adequate ventilation. Cylinder temperature should not exceed 250 F (121 C). Avoid breathing gas. Do not get liquid in eyes, on skin or clothing. Close valves to isolate tank for maintenance operations. Use in accordance with operation manual.

UN 1972 – P/N 3835959: This

P/N 3835959

P/N 3830599

METHANE REFRIGERATED LIQUID

FLAMMABLE GAS

UN 1972 2

P/N 3830619

ALWAYS KEEP CONTAINER IN UPRIGHT POSITION. THIS SIDE UP

FIRST AID: IF INHALED, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Call a physician. IN CASE OF FROSTBITE, obtain immediate medical attention. DO NOT REMOVE THIS PRODUCT LABEL.

P/N 3830709 24

IX APPENDIX – Tank Specifications LNG Tank Length — Volume 160

   )   s   n 140   o    l    l   a 120    G    (   e 100   m   u    l   o 80    V   s   s 60   o   r    G

16" Dia 20" Dia 22" Dia 24" Dia 26" Dia

40 20 0

20

30

40

50

60

70

80

90

Overall Length (Inches) LNG Tank Weights

140 120 100    )   s   n   o 80    l    l   a   g    (   y 60    t    i   c   a   p   a    C40

Empty Weight Full Weight

20 0 0

25

100

200

300

400

700 600 500 Weight (pounds)

800

900

1000

1100

1200

 A Chart Industries Company 

P/N 3835849 Rev C.1 7/02