Basic Well Head Control Panel
Description WHCP Basic Instrumentation
WHCP as known Well Head Control Panel. Installation of WHCP is near the well, usually insi inside de of WHCP WHCP cont contai ains ns pneu pneuma mati tic c comp compon onen ents ts,h ,hyd ydra raul ulic ic comp compon onen ents ts and and othe other r instrumentations. •
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Pneumat Pneumatic ic compone components: nts: 3-way 3-way pilot pilot valve, valve, 3-way 3-way push button, button,pne pneumat umatic ic pressur pressure e switch, pressure regulator etc. Hydrau Hydraulic lic compone components: nts: interfac interface e valve valve (pneumat (pneumatic ic to hydrauli hydraulic), c), hydraul hydraulic ic pump, pump, hydraulic reservoir tank, PSV etc Instrumentations: Instrumentations: Pressure gauge, chart recorder recorder (pressure,tempera (pressure,temperature,and ture,and flown rate), pressure switch (PSLL,PSHH), temperature gauge etc.
All that components components installed together together in WHCP to do as control function to operate the well. Control line in WHCP usually using stainless tubing, the size 1/4",3/8" and 1/2". Generally WHCP using control pneumatic combined with control hydarulic. By WHCP we can operate the well to shut in or running the well. Here an example of main part well head:
The legend: X : Well head (X-mastree) X00: DHSV (down hole master valve) X01: isolation valve X02:Master valve X03:Wing valve X04: Manual choke valve X05:Manual isolation valve X06: SDV (shutdown valve)
Function WHCP Basic Well Head Control Panel As mention in other article, the main function of WHCP is to control the well, basically to open or close the main shut off valve which installed on well head. Usually each well has three main shut off valve : Wing valve, Master valve (surface master valve) and DHSV. Those valves can be closed by using local push button on WHCP or activated from ESD system. Same as PLC or other controller which has input and output, in WHCP also has it. Input WHCP: Usually from signal ESD like PSLL,PSHH,Fusible plug and emergency push button. Output WHCP: Usually signal command to final control element (Wing valve,Master valve,DHSV and SDV if flow line installed it), signal indicator (local pneumatic indicator). WHCP equipped with local chart recorder, means it can be used to record the pressure,temperatur and flow rate of well.
Function or application of wellhead control panel
Gas wells and oil wells has a high potential hazard, either because the material ejected flammable nor the potential hazard of the gas pressure is high. Making oil well or gas well in X-mastree (well his head) are always installed valve. Its function is to shut down the well in case conditions that harm or for other interventions as well as the work test, etc. Here I will only discuss WHCP from gas wells, as I understand. Function or application WHCP depending of each type of wellhead control panel . There is a simple, until there is a tricky. If it can be inferred is actually a function of well head control panel is to operate well, be it for shut in and POP (put on production). With the wellhead control panel we able to open or closed the DHSV via the push button contained in panel. Also we can also open or close a master valve or wing valve with button push button as well. It was all done manually, by pressing or pulling a button push button. But to close the DHSV, Master valve, Wing Valve can be done automatically, namely through the integration with shutdown system from the well. Surely this should follow the philosophy of the shutdown system used by each company .
By looking at the picture, then it will give an overview of what functionality or usability of the wellhead control panel. The components iare visible in the picture can be grouped into: All of these components will give feedback or as a input signal to the Wellhead control panel (WHCP). While in the well itself (flowline) there is a sensor that is used to monitor the condition of the well, either to shutdown the system, or just f or readability only. Instrumentation for shutdown system e.g.: • • •
PALL (pressure switch low low) PAHH (pressure switch high high) The Fusible plug (for detection of fires), usually mounted above fangles, or parts that there is a possibility of leaks (the source of fire)
The instrumentation used for reading, for example: • • •
FR (flow recorder) PR (pressure recorder) TR (temperature recorder)
The Final element of the system shutdown: • • • • •
DHSV, Down hole Safety valve ( drived by hydraulic power) MV, master valve (drived by hydraulic power) SSV, surface safety valve (drived by pneumatic power) Choke valve, manually operated SDV (shutdown valve) installed in flow line of well, outside the part of the wellhead (X-mastree)
Valves are a part of which will receive command of the signal to be opened or closed from Wellhead control panel . So if I can give analogical WHCP is a controller (within the science control system), SSV, MV, DHSV, SDV are the part that receives the output from the controller, while the PALL, PAHH, fusible plug is the input of the controller. But don't imagine WHCP like PLC in General. WHCP I discuss here is that it uses control pneumatic or hydraulic. Why WHCP
generally use pneumatic control, because most of the well gas wells far location (remote) so hard to find sources of energy such as electricity. And generally WHCP from gas wells using gas from the well itself as a source of pneumatic power. Later will be discussed where the pneumatic power source to run the WHCP. With pneumatic power from gas, we can also have hydraulic power, i.e. by install the hydraulic pump on run by pneumatic power. Hydraulic power is used to run valve actuator which relatively large power needs. Pneumatic-powered convert hydraulic power can become larger. By using the pump.
