15-SAIP-50

Inspection Procedure 15-SAIP-50 Inspection Procedure for Conduit and Cable Seals Document Responsibility: Inspection Department

31 August, 2004

Saudi Aramco DeskTop Standards Table of Contents 1 2 3 4 5 6

Scope........................................................... Purpose........................................................ Abbreviation.................................................. References................................................... Inspection Procedure.................................... Inspection's Reporting Methods...................

Previous Issue: 31 December, 2000 Next Planned Update: 1 September, 2008 Revised paragraphs are indicated in the right margin Primary contact: Nasser M. Balhareth on 874-6604

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Document Responsibility: Inspection Department Issue Date: 31 August, 2004 Next Planned Update: 1 September, 2008

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15-SAIP-50 Inspection Procedure for Conduit and Cable Seals

Scope 1.1

This Inspection procedure describes how to inspect conduit and cable seals used in hazardous locations and will include verification of suitable location use of approved materials and a proper installation.

1.2

This SAIP is intended to establish a standardized methodology by Saudi Aramco inspection personnel in the implementation of inspection programs within Saudi Aramco facilities. The SAIP shall not be included in purchase order or contract documents issued to outside agencies.

Purpose The purpose of this procedure is to present all of the relevant information needed to assure that seals are properly installed and to ensure that all inspections are done uniformly.

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Abbreviation CSD

Consulting Services Department

SAEP

Saudi Aramco Engineering Procedure

SAIP

Saudi Aramco Inspection Procedure

SAES

Saudi Aramco Engineering Standard

NEC

National Electrical Code

References NEC Article 500 through 504 SAEP-1150

Inspection Coverage on Projects

SAES-B-068

Electrical Area Classification

SAES-J-902

Electrical Systems for Instrumentation

SAES-P-104

Wiring Methods and Materials

DC-950043

Electrical Connections for Field Mounted Instruments

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Document Responsibility: Inspection Department Issue Date: 31 August, 2004 Next Planned Update: 1 September, 2008 5


Inspection Procedure Seals are made mandatory by the National Electric Code (NEC), Article 501-5. The following step-by-step instructions provide direction for the proper inspection of most conduit seals. Special applications not covered should be reviewed with CSD prior to installation. 5.1

5.2

5.3

Incorrect design and installation of hazardous area seals are the most prevalent problems electrical inspection encounters in the field. Specifically problems in conduit/cable seal installations are: 1)

Seals improperly located in the wiring system.

2)

Improper selection of seals for particular applications.

3)

Improper installation (position, damming and pouring).

The major purposes of conduit and cable seals are as follows: 1)

Prevent the passage of gasses or vapors from one portion of a conduit system to another.

2)

Prevent the passage of gases or vapors through the cable core and cable interstices on multi-conductor cables.

3)

Limit an explosion to the enclosure in which it occurs.

Preparation 5.3.1

It is the inspector's responsibility to identify missing and/or excess sealoff devices as well as to inspect the devices. A careful study should therefore be made of the pertinent drawings to ascertain that all the necessary boundary and equipment seal-off devices are called out on the drawings. Unnecessary seal-off devices should be brought to the attention of the construction agency or responsible maintenance group.

5.3.2

Identify any situations where it is not possible to go strictly by the NEC or applicable SAES and make a decision on possible trade off's for these situations based on experience and/or conferences with CSD. Waivers may be required.

5.3.3

Instruments (transmitter, transducer) that have potted leads, and solenoids with low operating temperature, do not require seals per the NEC. However, subsequent replacements may not have potted leads for the instruments, and the solenoid may have an operating temperature

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higher than 80% of the auto ignition temperature in degrees Celsius of the gas involved. For the preceding reason, all instruments and solenoids shall be sealed per drawing AC-036561 to insure plant safety. Exception: Thermocouple and Resistance Temperature Detector conduit seals shall be installed in accordance with the NEC.

5.3.4

5.4

Determine the type of marking system that will be used for the inspection, i.e., tags, paint, etc., (experience has proven that it is better to make these inspections by area rather than by system, if possible. This eliminates a great deal of confusion. This is not always possible).

First Inspection 5.4.1

The first inspection should be made after all seal-off devices have been installed and dammed but before the compound is poured.

5.4.2

The following items should be checked: 1)

Make certain that all necessary devices are installed.

2)

Determine that the dam has been properly installed. This includes determining that the lower end is dammed for vertical seals and both ends are dammed for horizontal seals.

3)

In the case of the cable seal (See 5.1 for cable seal definition) make sure that the conductors have been properly separated so that the compound will flow between them. Metal tools should not be used for this purpose as the cable could be damaged.

4)

Assure that the conductors are not against the wall of the seal.

5)

Assure that a full five threads of the conduit have been engaged by the seal off device.

6)

Assure that the cable sheath is brought high enough so that it will end inside the compound.

7)

In the case of twisted pair multi-conductor cables, the twisted pair will not be separated for Class I, Div. II areas. For Class I, Div. I areas twisted pairs must be opened so that the compound can surround the individual conductors. Individual pair's grounding shield must be taped to prevent accidental grounding within the

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seal fitting. To accomplish all this, oversized seal fitting might be required. 5.5

Second Inspection 5.5.1

The second inspection should include witnessing the proper mixture of the compound and pouring it. Commentary Note: Use cold and pure water for mixing the compound, unless if it is specified otherwise in the manufacturer catalog.

5.5.2

The compound should only be poured once, i.e., a second pour after the first has hardened would probably leave a void.

5.5.3

In the case of a drain seal, make certain that the rubber drain hole was properly placed during pour and hardening.

5.5.4

Ascertain that sufficient compound was poured to give a thickness at least equal to the width of the conduit but not less than 5/8 inch thick.

5.5.5

If possible, pouring should be done at an ambient temperature of 100° or less. Otherwise, the compound will not cure properly.

5.5.6 The pouring plug should be left off for at least 24 hours to allow for proper drying and curing. Unless if it is specified to be closed by the manufacturer. For example, Crouse-Hinds require closing the seal fitting's plug immediately after pouring. 6

Inspection's Reporting Methods Any deficiencies in the above Mentioned methods or procedures should be reported by one of the methods outlined in SAEP-1150, Inspection Coverage on Projects, or through the worksheet system within the operating plants.

31 August, 2004

Revision Summary Revised the "Next Planned Update". Revised Section 4 to add "through 504". Revised Section 4 to add references names. Revised Section 5.5.1 to add the commentary notes. Revised section 5.5.6 to add" Unless if it is specified to be closed by the manufacturer. For example, Crouse-Hinds require closing the seal fitting's plug immediately after pouring".

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15-SAIP-50

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