| Reference Documents | ||
| 1.20.10 | Selection of Cleaning Agents and Methods for Equipment in Oxygen Service | |
| 3CB00003 | Requirements for Perlite Insulated Cold Boxes | |
| 3PI55005 | Piping Sealants and Threading Compounds for Oxygen Service | |
| 3ES30600 | Materials for Oxidizer Service Application Guidelines | |
| 4PI55002A | Piping Specification Standard Notes | |
| 4PI55005 | Pipe Thread Sealants Service Index | |
| 4WCB-30001 | Cold Box Penetration Details | |
| 4WCB-70001 | Cold Boxes, Sealing for Shipment | |
| 4WMA-007017 | Shop Alignment Tolerances for Distillation Columns and Cold Boxes Containing Distillation Columns | |
| 4WMA-007018 | Site Plumbness Tolerances for Distillation Columns and Cold Boxes Containing Distillation Columns | |
| 4WPI-FWAJ10 | Transition Joint Installation | |
| 4WPI-SW70002 | Process Clean (Class B) Inspection and Acceptance Requirements | |
| 4WPI-SW70003 | Oxygen Clean (Class AA) Inspection and Acceptance Requirements | |
| 4WPI-VALV02 | Mounting Plate Installation Procedure for Fully Extractable Valves | |
| 4PI57902 | Flanged Assemblies Bolting Materials and Procedures | |
| 579.03 | Gaskets for Pipe and Equipment Flanges | |
| 4WCB-50003 | Perlite for Cold Box Insulation | |
| 4WCB-50002 | Mineral Wool for Cold Box Insulation | |
| 4WCE600276 | Packing Process Equipment Jackets with Mineral Wool | |
| 4WCE600277 | Perlite Loading of Process Equipment Jackets and Field-Erected Storage Tanks | |
| 4WCE640130 | Fabrication of Structural Steel | |
| 4WCE640131 | Fabrication of Miscellaneous Metals | |
| 4WEQ6804 | Painting and Corrosion Protection for Design Temperatures to 649 C (1200 F) | |
| 4WCE-670200 | Process Piping | |
| 4WPIEW44001 | Pressure Testing Process Piping and Equipment | |
| 4WPI-FWZM01 | Field Installation of Expansion Joints and Flexible Hoses. | |
| 670.231 | Dimensional Tolerances for Cold Close Radius Pipe Bending and Forming | |
| 680.001 | Cold Box Shop or Field Fabrication | |
| 683.001 | Shop-Fabricated Cold Boxes Shipping Pipe Supports | |
| 683.015 | Cold Box/Can Expansion Joint Installation Instructions | |
| 683.200 | Cold Box Field Attachments Standard Details | |
| 4ACB-684001 | Cold Box/Can Temperature Element Wiring Installation Procedure | |
| 4ACB-684002 | Temperature Element Terminal Boxes for Cold Boxes and Cans | |
| 685.002 | pH Determination of Mineral Wool | |
| 685.003 | Packed Density Determination of Mineral Wool | |
| M01 | Site Cleaning of Piping, Vessels, and Valves | |
(Verify specification numbers are correct)
1. Preparation
1.1 Review specification 680.001 for procedures on inspections and specific tests that must be performed and documented during fabrication. The contractor is required to turn in a Quality Control (QC) binder at the end of the job which is detailed in 680.001.
1.2 Review the project generated cold box fabrication specification, for specific information and concerns related to the cold box being fabricated.
1.3 Hold a kick-off meeting with the contractor as defined in specification 4WCE-600001. Discuss items in 680.001 such as schedules, welding, inspections, pipe cleaning, testing, and quality control documents.
1.4 Verify that all ASME Weld Procedure Specification (WPS), Weld Procedure Qualification (WPQ), Procedure Qualification Record (PQR), Braze Procedure Specification (BPS), and Braze Procedure Qualification Record (BPQ) documents have been reviewed and approved. Copies must be kept in the project QC binder.
1.5 Air Products has the option to witness every inspection listed in 680.001 as well as others as deemed necessary. In 680.001 there is language giving Air Products right of rejection of poorly fabricated pieces, or when an inspection wasn’t done that was specified to be done.
1.6 Inspect all Air Products supplied vessels and piping upon arrival at the fabricator’s facility and prior to unloading. Note any damages including indentations, score marks, blisters, distortions, and cracked welds. After documenting their condition release the equipment to the contractor.
2. Frame Work
(Note: Looking at Audit #8 (Structural Audit) and 640.130 will help with some aspects of this work.)
2.1 Verify the support points on the shipping side of the box are correct and adequate.
2.2 The support bed, box frame, and column saddles must be within 3mm (1/8”) of level. The front left corner column is the most critical since this edge is used to check the box vertical alignment.
2.3 Verify dimensions against design drawings are within specified tolerances.
2.4 Verify that the frame is square by checking diagonal dimensions.
2.5 Check the frame leveling as shown in 680.001. The final measurements shall be documented and placed in the QC binder.
2.6 Verify that all frame diagonals (size, location, welds, etc.) are installed correctly.
2.7 Check the column bolster and record the hole and slot dimensions and locations.
2.8 Verify that the base is square to the front side and that the base welding is per design both inside and outside.
2.9 Check the expander pedestal to make sure it is flat, level, and square.
2.10 Verify that the lugs are installed in the proper locations.
2.11 Check that the lifting lugs are drilled (not burned) and that all hole sizes are correct.
2.12 Make sure that all lug welds are the proper size both in length and throat depth. Welds shall be inspected using dye penetrant or magnetic particle inspection methods. Documentation shall be placed in the QC binder. In addition, these reports shall be forwarded to the project engineer for inclusion into the erection contract.
3. Panel Work
3.1 Make sure that all welded surfaces are ground flush for all external or panel attaching surfaces.
3.2 Verify that weld pickup puddles are ground smooth.
3.3 Verify that the roof has a proper pitch to permit proper drainage.
3.4 Cold box roof shall be covered with checkered plate to provide slip resistance.
3.5 Ensure that the roof panel seal welding is complete and tested for water tightness.
3.6 Inspect finished panels for complete welding, weld pickup, or warpage.
3.7 Verify that the base vent screens are installed and welding is complete.
3.8 Verify that all exterior welding is complete and 100% free of porosity and gross irregularities.
3.9 Check exterior welding again after surface preparation prior to painting.
3.10 Verify that all penetrations are in the correct locations within correct tolerances and the proper materials are used. A non-conformance report shall be issued for those penetrations out of specified tolerances and forwarded to project engineering for resolution. Specific details on penetrations are given in 4WCB30001. The contractor shall record the as-built location of all penetrations and a copy shall be included in the QC binder.
4. Equipment and Piping Cleaning
4.1 The fabricator needs to clean all pipe to Class B or Class AA as stated in the fabrication package. In Air Separation Unit (ASU) cold boxes all piping and in-line components shall be AA clean. The requirements of Class B and AA cleaning can be found in 4WPI-SW70002 and 4WPI-SW70003, respectively. Audit #7, (Piping and Pressure Testing), also has a section on pipe cleaning.
4.2 Approved cleaners can be found in the Air Products Standard 1.20.1 or in 3ES30600.
4.3 APE spec M01 references common chemical names generally available overseas, and is similar to pickling.
4.4 The contractor needs to provide a cleaning procedure for review and approval. Approved documentation shall be placed in the QC binder.
4.5 Inspections shall be performed after cutting and fit up, prior to making joints with backing rings, and prior to making joints that prohibit a straight-line view for inspecting internal surfaces.
5.6 Witness and confirm cleaning inspections. Ensure that complete records of all cleaning are being kept in the Cleaning Inspection Log as given in 680.001. Copies shall be placed in the QC binder.
4.7 Verify that cleaned items are properly protected from the time of acceptance through installation. This will require periodic inspections of pipe in the storage and installation areas.
4.8 Confirm that all cleaned pipe stored outdoors or shipped separately from the cold box assembly has all pipe ends and fittings sealed weather-tight with plastic or metal pipe caps. Flanged ends shall be sealed with metal blinds and rubber gaskets.
4.9 Ensure the open ends of pipes, valves, and other components are kept capped until final connections are made. Wood or rag plugs or covers shall not be used.
5. Equipment Installation
5.1 Audit #5 (Machinery and Equipment), covers equipment handling, and has portions that are applicable here.
5.2 Upon receipt, verify the shipping pressure for all pressurized vessels by attaching a provided pressure gauge to each circuit valve. The pressure reading shall be recorded for the QC binder as listed in 680.001. If the vessel or equipment is received without positive pressure a non-conformance report shall be completed and specifier notified for resolution.
5.3 Columns and other equipment shall be set level and true in their proper orientation. The front left corner of the box is the reference point and alignment line for the columns and other equipment. Specification 680.001 details horizontal and vertical deviation tolerances.
5.4 Additional requirements for column alignment can be found in 4WMA-007017 for shop work and in 4WMA-007018 for columns erected vertically on site. Final equipment alignment deviations need to be recorded and kept in the QC binder.
5.5 Verify the location and orientation of all installed vessels including distance from cold box wall.
5.6 Check that all vessel nozzles are square and oriented correctly.
5.7 Some vessels may have adsorbent installed and are slightly pressurized. The vessels shall be depressurized and caps for these vessels removed only when all connecting piping to the first block valve can be attached in less than 12 hours. It is imperative that contact with ambient air is minimal.
5.8 Ensure that adsorber vessels are opened, fitted, and welded only with an Air Products representative present.
5.9 Inspect all equipment nozzles and the vessel interiors for cleanliness just before connecting piping spools. Remove desiccant bags and verify against quantity installed prior to shipment. Section #4 in this audit discusses inspection requirements. Their condition needs to be documented and a record kept in the QC binder.
5.10 Check joint preparation of pipe to vessel nozzle connections.
5.11 Make sure that all equipment anchors, support welding and support installation details are in accordance with the design drawings and details.
5.12 Make sure that any Klingersil material is installed in accordance with fabrication drawings and details. This will usually be on the vessel sliding supports.
6. Piping Installation – Preparation
6.1 Piping work is covered in Audit #7 (Piping and Pressure Testing) and shall be reviewed. Specification 4PI55002A and 4WCE-670200 should be reviewed as well.
6.2 Check all lines for proper material of pipe, fittings, and type; size, length of bolting hardware. Ensure to include certification documents in the QC binder as required.
6.3 Check individual spool dimensions. All pipe bends need to conform to 670.231.
6.4 Make sure all spool pieces are permanently marked and are recorded on a check sheet.
6.5 Verify contractor welding consumables, materials and equipment are in compliance with the specifications.
6.6 Confirm that the fabricator is recording details for each weld. Consult the log sheet given in 680.001 for requirements. Periodic checks are recommended to confirm that the contractor is updating the logs regularly.
6.7 Discuss with the contractor about the use of welding dams in regards to specification requirements. There needs to be a record of where dams were used, and when they were removed so that no dams are left behind.
7. Piping Installation – General
7.1 Verify that all welded or brazed joints are clearly and permanently marked by the welder to indicate their assigned identification number. Markings shall be made by use of electric pencil, rubber stamp, permanent marker or metal stamp as allowed by the applicable code and piping specification. Method to be used will be dependent upon type of base pipe material.
7.2 Downhill welding is not permitted unless approved in writing by the Air Products representative.
7.3 Slag from stick welding shall be removed before welding the next pass.
7.4 The finished weld shall be uniform in appearance with the edge of the weld merging smoothly into the base metal.
7.5 Make periodic checks of piping fit-ups and installations to ensure that pipe is not being pushed or pulled which creates stress and strain in the piping system or connecting equipment. Cold springing is not allowed.
7.6 The longitudinal seams of welded pipe in adjoining pipe sections need to be staggered.
7.7 Verify that all large fabricated tees and mitered bends are back-welded on the inside.
7.8 Check branch and weld-o-let connections to ensure 100% penetration. Branch connections cannot intersect the longitudinal seam of welded pipe headers.
7.9 Branch stub-in welding is not permitted unless specifically noted on the drawings.
7.10 Verify that piping seal loops are located at proper elevations per contract drawings.
7.11 Check that flow elements and orifices are completely installed and documented. Record this information as shown in 680.001 and keep a copy in the QC binder.
7.12 Make sure that flow meter orientations are correct per the contract drawings and have proper upstream and downstream straight-line distances. Meter runs shall be installed without the use of backing rings.
8. Piping Installation – Aluminum
8.1 Welding machines are the root of many aluminum welding problems. Recommended welding machines can be found in 680.001. Additional requirements are listed in Appendix D of specification 4WCE-670200; including power supply, welding torch, water cooler, electrodes, gas cup sizes and gas supply.
8.2 Make sure the contractor leak checks all hoses before starting. Leaks in purge hoses can cause an increase in weld porosity.
8.3 Check regularly to ensure that correct filler materials are used, especially that no high silicon content aluminum alloy filler materials are used. There is a list of approved filler materials in Appendix D of specification 4WCE-670200.
8.3 Plain backing rings shall be used for all aluminum pipe welds unless an alternate is approved by Air Products prior to award of the contract. See Appendix D of specification 4WCE-670200 for dimensions.
8.4 Aluminum socket welds are more likely to leak and be damaged than other welded joints. Make sure all aluminum sockets are dye penetrant checked and inspected thoroughly during the pneumatic leak test. Other weld examination requirements are listed in Appendix D of specification 4WCE-670200.
8.5 All cleaning is to be done using stainless steel wire brushes, grinding wheels are not allowed.
9. Piping Installation – Stainless Steel
9.1 Confirm that stainless steel pipe is cut using mechanical devices or plasma arc cutting torches. If plasma arc cutting is used, the cut surface must be ground or sanded to bright metal before further fabrication.
9.2 Inert gas shielded tungsten-arc welding, known as GTAW, of the root pass is required.
9.3 Backing rings shall not be used on stainless steel piping welds. A backing ring may be used for a final closure weld only if approved in writing by Air Products.
9.4 Confirm that the welds of orifice flanges on stainless steel piping are made without backing rings, and that the welds are ground internally, so that the inner diameter at the weld is within one percent of the published inner diameter for the pipe specified.
9.5 The distortion tolerance of welded joints is less than 1% of the inside diameter or 1.5mm (1/16”)
9.6 Conduct Charpy impact tests as called for in welding procedure.
10. Piping Installation – Silver Brazing
10.1 Check that the brazing procedures have been approved and are being followed. Many contractors are very lax on following brazing procedures.
10.2 All copper-to-copper or copper-to-stainless joints shall be brazed.
10.3 Fittings that were once brazed shall not be reused.
10.4 Whenever possible, the inside of the brazed joint should be visually inspected.
10.5 Brazing work must be kept away from threaded connections with thread sealant and other heat sensitive items such as valves with non-metallic seats.
10.6 Check all brazed joints for incomplete fillets or excess brazing alloy and evidence of base metal melting. Remove suspect joints.
10.7 Select completed joints randomly and perform a section test to check the reliability of the brazing The contractor pays for joints that are found not acceptable.
10.8 Ensure that all valve seats are cleaned and checked after brazing to ensure removal of flux and brazing alloy.
10.9 Verify that copper instrument lines are blown down, after the completion of the circuit pressure test to ensure that the lines are not plugged with brazing alloy or flux.
11. Piping Installation – Flanged and Threaded Connections
11.1 Review 579.02 and 579.03 for more information on flanged connections.
11.2 Confirm that threaded piping installations have as few joints as possible and that approved thread sealants are being used. Use 3PI55005 or 4PI55005A for reference.
11.3 Threaded couplings are allowed only when there is more than 5 meters (16’) of straight pipe between fittings.
11.4 Threaded unions should be used as located on the drawings or as required for proper assembly and disassembly. Unions shall not be used inside the cold box or on cryogenic fluid lines.
11.5 Some unions have a Teflon seal that needs to be removed before welding nearby.
11.6 Properly installed threaded connections do not need to be seal welded unless called for by either the contract drawings or the ORI (Operational Readiness Inspection punch list)
11.7 Flange faces shall be kept covered until installation for protection and cleanliness.
11.8 All flange bolt holes shall straddle the natural pipe centerlines in all directions unless noted differently on the isometric pipe drawings.
11.9 Verify that all slip-on flanges are welded on both the inside and outside of the pipe.
11.10 Check that flange studs are of the correct material and length and that they have been properly torqued. Verify that the nut is fully engaged and at a minimum flush with the nut.
11.11 Make sure that all flange nuts and studs have been torque checked. See 579.02 for a bolting procedure and torque levels. Document the final torque levels for the QC binder.
12. Temperature Element Installation
12.1 Review 4ACB-684001 for specifics on temperature element installation. Specification 4ACB-684002 has information on the terminal box installation.
12.2 Review the project generated cold box fabrication specification to learn the type of temperature elements installed in the cold box and what testing is required.
12 3 Check all thermo-wells, temperature elements, and couplings for correct installation. Thermo-wells should extend midway into the pipe for pipe diameters up to 300mm (12”).
12.4 Seamless EMT (Electrical Metallic Tubing) and aluminum or rigid fittings with compression style adapters must be used inside the cold box. Screw type adapters are not permitted. All conduit and fittings outside of the cold box must be rigid galvanized.
12.5 A conduit seal fitting must be used between the cold box face and the terminal box, to prevent purge gases from migrating into the terminal box.
12.6 The terminal box should have 2” air gap between it and the cold box face to minimize frosting inside the terminal box, unless the shipping profile dictates otherwise.
12.7 RTD (Resistant Temperature Device) wire cannot have splices between the element and the terminal box. There should be enough cable left in the temperature element head to allow the element to be withdrawn from the thermowell without disconnecting the wires.
12.8 Most project cold box fabrication specifications call for spare RTD wires to be installed for each temperature element. Ensure this wire is installed and tested.
12.9 RTD wire shall be landed on the terminal box strip without crimped attachments. Crimped attachments are needed for the connection inside the temperature element head.
12.10 There are multiple tests that are needed at various stages for temperature elements. Please review these as listed in 4ACB-684001. Test results are to be included in the QC binder as defined by the specification.
13. Valve, Transition Joint, Expansion Joint, Flexible Hose and Instrument Installation
13.1 Review 683.200 for details on all instrument taps, sample taps, and pressure indicator attachments.
13.2 Verify that all valves and instruments such as flow elements, orifice plates, and check valves are installed in accordance with the flow direction shown on the process and instrument diagrams (P&ID) and isometric drawings. When a discrepancy exists the P&ID rules.
13.3 Samson valves have stringent assembly, storage and disassembly requirements. Ensure the Samson valve shipping and installation Engineering Standards (reference specification numbers) are reviewed with the contractor.
13.4 Valves shall be open or have their internals removed before welding or brazing adjacent joints. See the manufacturer’s recommendations for specifics.
13.5 Valves with mounting plates shall be installed according to 4WPI-VALV02. The inner diameter of the mounting plate shall be fillet welded prior to the box panel fillet weld. Care must be used to avoid heat warping of the valve stem while fillet welding the plate.
13.6 Make sure that instrument lines are straight, vertical and horizontal, un-kinked, and that seal loops have been installed at the correct elevations
13.7 Review 4WPI-FWAJ10 for transition joint installation with the contractor. Review the manufacturer’s specifications and discuss weld cooling methods.
13.8 Prior to installation of all transition joints the Quality Assurance Transition Joint Check Sheet (Form 28) shall be initiated. Each joint shall be marked with a permanent water proof marker identifying the approiate line number next to the temperature indicator label. The fabricator shall then take a picture of the joint which shall include the line number ID and the temperature indicator label. This picture shall become part of the Quality Assurance documentation.
13.9 The fabricator shall install the transition joint in the piping system in accordance with 4WPI-FWAJ10.
13.10 Make sure all transition joints have undamaged heat indicating gauges before starting.
13.11 It is recommended that transition joints be welded into a subassembly outside the cold box first. Ensure that the proper cleanliness, weld spacing, and NDT requirements are followed for the transition joint welds.
13.12 After welding a transition joint, check the heat indicating gauge to make sure it was not overheated. Some joints can be overheated even when the gauge is not fully blackened. Those joints missing heat indication gauges need to be replaced.
13.13 After completion of the welding of both ends of the transition joint another picture shall be taken which shows both welded ends as well as the line number ID and temperature indicator label. This picture shall also become part of the Quality Assurance documentation.
13.14 If any transition joint is received without a temperature indicator label the fabricator shall not install the joint and shall notify Air Products immediately for further instruction.
13.15 If any transition joint fails to meet the inspection criteria established in 4WPI-FWAJ10 the fabricator shall notify Air Products immediately. The overheating of the temperature indicator label either by preheating the joint during the weld installation process will require the transition joint to be replaced.
13.16 Make sure all expansion joints and flexible hoses are installed as shown on the project contract drawings. They shall not be used to correct piping misalignments. Installation instructions are given in 4WPI-FWZM01 and 683.015.
13.17 The temporary supports on expansion joints need to be in place during installation. They shall remain if the box is going to be transported unpacked with rockwool. Temporary supports shall be removed prior to pressure testing. Expansion joints are flow sensitive and the flow arrow must align with the process flow.
13.18 Do not modify the expansion joints tie rods nor remove the tack welds from the nuts.
13.19 Flexible hose braids should be taut after installation but not bowed from compression of attached lines.
14. Support Installation
14.1 Review 640.130 and 640.131 for more specifics on supports.
14.2 Temporary supports left in place and improperly supported pipe or equipment are two common problems. Require the contractor to install the proper supports as the work progresses.
14.3 Verify that the correct equipment support material is installed as per the design drawings. Supports within the cold box frame should be aluminum or stainless steel.
14.4 Check that the bolts, nuts, U-bolts, and washers are in accordance with the design drawings.
14.5 Make sure that there is no gap between piping support attachments and the support steel.
14.6 Check to be sure that U-bolt nuts are tightened and that the double nuts are installed in correct orientation per support detail based on a guide-style or anchor-style support.
14.7 Make sure that a record of permanent pipe supports is documented as noted in 680.001, and a copy is placed in the QC binder.
15. NDT Requirements
15.1 Ensure that the radiograph identities are traceable to the welder who performed the weld and the date that the welding took place. A weld map shall be maintained to record this information.
15.2 For each rejected weld ensure tracer radiographs are performed for the specific welder associated with the original rejected weld.
15.3 Make a visual inspection of all joints and valves. Any joint that shows evidence of overheating, cracking, poor penetration or other defects shall be replaced.
15.4 Make a visual check of pipe and equipment support welding. Any areas in question shall be checked via NDE to verify acceptability. Rejected installations shall be reworked by the contractor.
15.5 All support lugs, trunions, and other supports welded to a pressure pipe shall be 100% dye penetrant examined.
15.6 The frame lifting lugs and trunions shall be subject to 100% dye penetrant or magnetic particle examination.
15.7 All fillet welds where instrumentation connects to a vessel or to process pipe shall be 100% dye penetrant examined. These items that are attached directly to the pipe wall shall be completed prior to pressure testing of pipe system.
15.8 All butt and mitered welds shall be subject to radiographic examination in accordance with ASME B31.3 and 680.001.
15.9 Unless specified otherwise, random radiography shall be performed a minimum of 5% of each welder’s diameter-inches. Each selected weld shall be 100% radiographed. See HyCO section in 4WCE-670200 for further requirements and an NDE logic diagram.
15.10 For each defective weld found, two additional (tracer) joints made by the same welder shall be promptly radiographed. If one or both of these tracers show unsatisfactory welding, additional welds made by this welder shall be radiographed, examining two welds for each tracer weld found to be unsatisfactory. Welds radiographed as tracer joints are not counted as part of the 5% sampling check.
15.11 Only x-ray examination shall be used for aluminum piping unless a variance is requested and approved due equipment not fitting into a confined area.
15.12 Ensure that all welds examined are recorded as shown in 680.001. The radiograph reader sheet shall contain all radiograph information and the final interpretation. A copy of the log shall be kept in the QC binder.
16. Pressure Testing
16.1 Review Audit #7 (Piping and Pressure Testing) and specification 670.219 for more information on pressure testing.
16.2 It is recommended that several panels be left off of the cold box until pressure testing is complete so that the confined space hazard is reduced.
16.3 An Air Products representative must flow check the box prior to any pressure testing.
16.4 Air Products shall supply the pressure test procedures for the pressure test unless defined differently in specification 600.002. The contractor shall provide calibrated safety relief devices, calibrated pressure test, and other piping and fittings in accordance with the specifications. Pressure testing of assemblies shall be carried out using dry, oil-free air or nitrogen at ambient temperature. Supply of the pressure test media is defined in specification 600.002.
16.5 Expansion joint support bars need to be removed before the pressure test.
16.6 Verify that all vessel nameplates are installed on the vessels.
16.7 Air Products shall witness the entire pressure test including soaping of lines, the proof test, and reduction test pressure to design pressure. See 670.219 for specifics.
16.8 Witness the soaping of lines. An Air Products representative needs to sign the pressure test documents accepting the pressure test. Copies of the signed pressure tests are to be included in the QC binder.
16.9 At the completion of the pressure, before full depressurization, blow out individual instrument taps to ensure there are no obstructions or blockages. Document that this procedure has been done.
16.10 Depressurization of systems shall occur in systematic way to verify each in line valve will hold system pressure. Valves that do no hold pressure shall be noted and leak rate recorded. Control valve may require a source of instrument air to hold valve in closed position. This information will be provided to project engineering to determine if leak rtes are acceptable or if valves require repair.
16.11 Check all expansion joints or flex hoses for damage or irregularities after the test.
17. Insulating – Preparation
17.1 Review Audit #11 (Piping Insulation), for QC concerns about insulation. Specification 600.276 has specifics on mineral wool. Specification 600.277 and 3CB00003 have specifics on perlite.
17.2 Ensure that the perlite or mineral wool meets the Air Products specifications 4WCB-50003 or 4WCB-50002 prior to installation. Home office approval is required. The home office might request samples to be sent in that will be tested there. Approvals shall be placed in the QC binder.
17.3 Specifications 685.002 and 685.003 define tests for mineral wool that the home office may ask to be conducted on site. Please review and conduct them if request for these tests is made.
17.4 Ensure the interior of the box is thoroughly inspected with a bright white light and cleaned of debris and unused construction material. All beams, equipment, and panels need to be free of debris, scale, and oil films.
17.5 If the cold box interior calls to have a coat of prime paint make sure there are no bare areas, paying special attention to weld zones and in tight places.
17.6 All tape or flags used for pressure testing shall be removed.
17.7 Ensure all shipping plugs are removed from the exchangers and other equipment. Ports shall be stuffed with mineral wool.
17.8 If the cold box will be insulated with both mineral wool and perlite, there should be a barrier between the two. Verify this barrier is installed per the design drawings.
17.9 Where there will be perlite, all purge ports need to have their screens or sintered filters installed. Ensure any temporary covers or bags on purge ports are removed.
17.10 Ensure that there are no mechanical joints that require future access in perlite zones. These should be in mineral wool only.
18. Insulating
18.1 Proper health precautions, such as good ventilation, coveralls, gloves, goggles, and respirators are required depending on the proximity to the insulating work and requirements of the material safety datasheet (MSDS).
18.2 A slight pressure held on the piping circuits during insulation work is required, with a depressurization alarm, to serve as an indicator of piping or instrument line damage during the insulation process. Media shall be oil free dry air.
18.3 It is important that all insulation be kept dry during insulating. Any wet insulation shall be removed and discarded.
18.4 Mineral wool needs to be packed to a density of greater than 14 lb/cubic foot with special attention to areas under frame supports and in tight areas between the frame and piping.
18.5 Perlite installation shall not begin until all valve cages are built and packed with mineral wool.
18.6 Perlite needs to be blown into the jackets until they are completely full. During the operation the contractor shall hammer on the sides with a rubber mallet or use skin vibration to prevent voids. See 4WCB-50003 for specifics.
18.7 All thermocouples shall be continuity tested during and after the insulation process to make sure that they are not damaged. Have the contractor document all results.
19. Painting
19.1 This is covered in more detail in Audit #15 (Painting) and specification 4WEQ-680 rev.1
19.2 All cold box exterior panels shall be blasted clean and prime painted before installation
19.3 If panels are installed first before blast cleaning and prime painting than see 4EQ-6804 for requirements.
19.4 All surfaces to be painted need to be cleaned and washed prior to a new coat of paint. Rust and other flaking material shall be removed with a wire brush manually.
19.5 Check elapsed time before painting and condition of surfaces. Verify type of paint, dry film thickness, and coverage of welds. 5 mils of dry film thickness (DFT) paint cover is the minimum. 3 mils of DFT is allowed for Direct-to-metal (DTM) coatings.
19.6 When painting the inside of a cold box is required by project specification, the inside surface of the removable steel panels and the concealed areas under bolted panels shall receive a prime coat of paint only. No other areas of the inside of the cold box get paint.
19.7 Items projecting outside the cold box that are made of stainless, aluminum, copper, brass, or galvanized shall not be painted.
19.8 Ensure that the fabricator completes the required QC forms as given in 4EQ-6804 and includes them in the QC binder.
20. Shipping
20.1 Verify that all the temporary shipping supports, bolts, and plugs have been painted yellow and that a log sheet identifying their locations has been completed. Review 683.001. A copy of the log shall be included in the QC binder and sent with the cold box with shipping documentation.
20.2 Ensure that all projecting valves are removed per the project specific fabrication specification. Place a match mark on each piece to be removed for correct field installation.
20.3 Properly pack and identify loose items such as valves, instruments, and tie-down lugs. Check that all hardware and gaskets required for field installation are included.
20.4 “AA” cleaned components must be properly sealed to avoid contamination.
20.5 Confirm that the duplicate vessel nameplates are properly installed. A photocopy of them shall be placed in the QC binder.
20.6 Check external dimension of width, height, and length against shipping drawing requirements.
20.7 Witness weighing of box and make sure information is immediately submitted to AP home office. Obtain a copy of the calibration certificates of the weighing equipment and scale accuracy information for use in field rigging procedures and for the QC binder.
20.8 Ensure that all piping or nozzles have been securely capped.
20.9 Place nitrogen purge on piping systems prior to shipment. Record pressure of each circuit and place in QC log. Additionally, place warning signs on purge injection valves stating that pipe systems are under pressure and shall not be depressurized until receipt at site.
20.10 Double check that all previous non-compliance items have been corrected.
20.11 Review specification 4WCB-70001 which covers sealing the cold box for shipment. Packed boxes must be water tight to prevent entrance of rain or sea water during transport and storage. Pay special attention to all penetrations and tacked on panels.
20.12 Verify that all temporary equipment and pipe supports that are to be removed before shipment are removed from the cold box.
20.13 Verify the plans for transporting the box from the shop to the erection site or port.
21. QC Requirements
21.1 All of the forms given in 680.001 need to be completed and filed in a QC binder.
21.2 Review the final QC package for completeness and accuracy. Resolve any missing or incomplete QC documentation.
21.3 As-built information/drawings
21.4 Weld procedures and Welder qualifications for structural welds
21.5 Written confirmation of the adequacy of concrete strength prior to cold box erection Written notification to the steel erection contractor of all anchor bolt modifications or repairs Copies of all design approved changes to the structure, or for anchor bolt modification
21.6 Certified survey equipment calibrations records
21.7 Instrument tap flow and obstruction verification
21.8 MSDS sheets and approvals of all material substitutions
21.9 Torquing records of all flanged connections inside the cold box
21.10 Additional temperature element tests done
21.11 Cleaning procedure
21.12 Cleaning Inspection Log from 4WCE-670200
21.13 WPS, WPQ, PQR, BPS, BPQ
21.14 NDE reports and films
21.15 Frame leveling dimensions
21.16 Cleaning and inspection log
21.17 Weld maps and logs
21.18 Shipping and receiving pressure readings
21.19 Equipment alignment deviations
21.20 Vessel internal inspection documents
21.21 Material Test Reports (MTR’s)
21.22 bFlow check sign-offs
21.23 Torque records
21.24 Temperature element test reports
21.25 Record of permanent pipe supports
21.26 Pressure test documents Log of temporary supports Forms from specification 4WEQ-6904 Photocopy of nameplate Weight report Scale calibration certificate Purge log Include in the QC qualifying certifications of the NDT laboratory and of the technicians performing the work Eye test and certification records for NDT technicians Pressure test gauges and PSV calibration certificates Pressure test circuits signed and any marked up P&ID’s. Include other pressure test records including blind Log, QC-200, etc. Construction punch lists Any other requirements that are called out in reference documents that would apply here.