Table of Contents
| Section | Title | Page |
| Purpose | 2 | |
| Scope | 2 | |
| Related Documents | 2 | |
| Definitions | 4 | |
| Proposal | 5 | |
| General Requirements | 5 | |
| Materials of Construction—General | 6 | |
| Rotating Equipment | 6 | |
| Pressure Vessels | 7 | |
| Shell and Tube Heat Exchangers | 7 | |
| Instrumentation and Process Controls | 7 | |
| Pressure Relief Devices | 9 | |
| Electrical | 9 | |
| Piping | 10 | |
| Structural Steel | 11 | |
| Insulation and Heat Tracing | 13 | |
| Pressure Testing | 13 | |
| Painting and Internal Cleaning | 13 | |
| Shipping | 14 | |
| Engineering Deliverables and Documentation | 14 | |
| Tagging | 17 | |
| Change Log | 17 | |
| Flammable/Toxic Gas Service | 18 |
1. PURPOSE
- This engineering specification defines the general requirements of packaged process systems.
2. scope
2.1 This specification, together with the equipment specification, applies to the design, fabrication, inspection, testing, painting, and shipment of packaged process systems which will be mounted on skidded systems or modules.
2.2 Appendix A applies when the packaged process system is in flammable or toxic gas service.
2.3 This specification includes requirements pertaining to the following equipment for packaging:
- Pumps
- Fans
- Heat Exchangers
- Blowers
- Pressure Vessels
- This specification does not apply to:
- Supplier standard utility packages such as packaged boilers, refrigeration systems, and instrument air drier systems.
- Process and reciprocating compressor packages.
2.5 Project-specific requirements related to a particular service will be defined in the equipment specification. Examples include piping specifications and internal cleaning requirements.
2.6 Requirements for the following items are not included in this specification and will be defined in the equipment specification as needed:
Lighting
Piping specifications
Process requirements, such as allowable pressure drop and line sizing criteria
2.7 The supplier shall furnish all detailed engineering and design, equipment supply, and skid fabrication.
2.8 All skids and equipment modules will be installed on foundations provided by others.
2.9 The supplier shall provide all interconnecting piping between skids and any off-skid equipment that is part of the packaged process system.
2.10 Each skid shall have all equipment installation, piping, wiring, and both prime and finish painting completed before shipment. Skids shall be ready for field tie-ins for piping, wiring, and instrumentation after they have been set on their foundations
2.11 All field construction activity will be provided by others.
3. related documents
3.1 Air Products Engineering Documents
3.1.1 Mechanical Equipment
4WEQ-1051 Welding of HyCO Plant Equipment
4WEQ-1010 Supplier-Designed, Shop-Fabricated Pressure Vessels
4WEQ-1020 Insulation Supports for Warm- and High-Temperature Heat Exchangers and Pressure Vessels
4WEQ-1105 HyCO Plant Positive Material Identification (PMI) Requirements
4WEQ-1430 Shell and Tube Process Heat Exchangers and Compressor Coolers
4WGN-20001 Supplier Quality Requirements
4WME-551002 Centrifugal Fans
4WME-556001 Critical Centrifugal Pumps and Auxiliaries
4WME-556002 Ring Section Boiler Feedwater Pump
4WME-556003 General Purpose Centrifugal Pump for Water Service
4WME-55623 Single Stage, High Speed Centrifugal Hydrocarbon Pumps
VDR Set Vendor Documentation Requirements (for Packaged Process Systems and applicable specific items)
3.1.2 Piping
4WCE-670200 Fabrication and Erection of Process Piping
4WPI-FWZM04 Perforated Conical, Truncated-Cone or Weld End Truncated-Cone Strainers Fabrication Specification
4WPI-PW45001 Perforated Conical, Truncated-Cone and Weld End Truncated-Cone Strainers
3.1.3 Electrical
4AEL-620302 Standard Wire and Cable Types
4WEL-52312 NEMA Standard Reliability Low Voltage Induction Motors
4AEL-620301 Hazardous Area Requirements for Class I Areas
4AEL-620305 Electrical Work on Equipment Skids
STD-P306A Electrical Standard-Conduit Connection-Solenoid Valve
STD-P308A Electrical Standard-Conduit Connection to Pigtailed Switch
STD-P310A Electrical Standard-Conduit Connection to Pigtailed Low Level Devices
STD-P314A Electrical Standard-Temperature Element Connection
3.1.4 Process Controls
3PS15002 Use of Thermowells in Pressurized Systems
3PS25001 Minimum Lengths of Straight Piping Required for Primary Flow Elements
4WPS-TEMP02 Resistance Type Temperature Detectors (RTDs) for Cryogenic and General Service
4APS-630290S Instrumentation Work on Equipment Skids
4API-630292 Instrument Air Supply Piping Specification
3.1.5 Safety Relief Valves
4WPI-EW80010 Safety Relief Valves
3.1.6 Structural Steel
4ACS-640130 Fabrication of Structural Steel
4ACS-640131 Fabrication of Miscellaneous Metals
4ACS-640132 Structural Steel Erection
309710D Standard Ladders and Safety Gates Drawing
309711D Standard Stairs Drawing
309712D Standard Handrails Drawing
3.1.7 Painting
4WEQ-6804 Painting and Corrosion Protection of New Construction for Operating Temperatures to 649°C (1200°F)
3.1.8 Insulation
3PI99001 Thermal and Acoustic Insulation Guideline
3.2 American Institute of Steel Construction (AISC)
AISC 360 Specification for Structural Steel Buildings
3.3 American Society of Mechanical Engineers (ASME)
BPVC, Section VIII, Div. 1 Pressure Vessels
B31.3 Process Piping
B73.1 Specification for Horizontal End Suction Centrifugal Pumps for Chemical Process
3.4 American Welding Society (AWS)
D1.1 Structural Welding Code Steel
3.5 International Conference of Building Officials (ICBO)
Uniform Building Code
3.6 National Fire Protection Association (NFPA)
70 National Electrical Code
3.7 Welding Research Council (WRC)
Bulletin 107 Local Stresses in Spherical and Cylindrical Shells Due to External Loadings
3.8 Instrumentation, Systems, and Automation Society (ISA)
75.01.01 Flow Equations for Sizing Control Valves
- DEFINITIONS
- A packaged process system is custom designed and fabricated by a supplier, and normally consists of one or more skids that perform(s) a specific process function. Examples include drier systems, CO2removal systems, and argon deoxo systems.
- Packaged System. A system which incorporates equipment, piping, instruments and electrical components in shop assembled modules. The system shall have minimal interconnections (electrical, instrumentation and piping) to other modules resulting in quick, easy re-assembly in the field. Factors to be considered when designing packaged systems are layout, fabrication, constructability, operability, and shipping. If a package system is too large to be mounted on a single module, it may be built in multiple modules composed of skidded sub-systems.
- Skidded System. An assembly of components, primarily piping and valves that are attached to a structural frame for support. The assembly may also contain vessels, heat exchangers, machines, instruments, controls, electrical equipment, and other equipment. Skidded systems are typically fabricated, assembled and tested at a fabrication shop, then transported intact to a plant site for installation
4.1.3 Modules. Discrete skidded systems which are based on a complete process function. The P&ID shall be optimally divided into modules to minimize interconnects and skidded subsystems. Each module shall precisely define the contents of a structural frame, piece of equipment or other support system for the components which make up the module. These components may include but not be limited to equipment, valves, instruments, piping and electrical equipment. It is anticipated modules will be built and staged by the same supplier.
- PROPOSAL
5.1 The following information shall be provided with the proposal:
5.1.1 Process Flow Diagram, showing the following:
Control loops
Valves and instruments
Materials of construction
Equipment
5.1.2 Preliminary heat and material balance, including a pressure drop profile through the system, and all streams exiting the skid battery limits.
5.1.3 Preliminary design pressures, design temperatures, and relief valve settings for each piping circuit.
5.1.4 Preliminary utility requirements.
5.1.5 Equipment list.
5.1.6 Preliminary equipment sizes and weights.
5.1.7 Quantity of skids.
5.1.8 Preliminary shipping envelope size and weight of all pieces shipped to the job site.
5.1.9 Preliminary equipment arrangement, including space required for bundle pulls and other routine maintenance.
5.1.10 List of suppliers for major equipment such as:
- Pressure vessels
- Heat exchangers
- Control valves, including model numbers
- Manual valves and check valves, including model numbers
- Instrumentation, including generic model numbers
5.1.11 Names of all software used for design, including the following activities as a minimum:
- Process modeling
- Heat exchanger rating
- Pipe stress
5.1.12 Preliminary list of equipment and bulk materials being shipped loose.
5.1.13 Preliminary schedule showing significant milestone dates in weeks after award. Milestones shall include delivery of drawings, ordering major equipment and materials, beginning of fabrication, and shipping date.
5.1.14 Inspection plan for in-house and subcontracted work.
- GENERAL REQUIREMENTS
6.1.1 All equipment shall be skid mounted to the fullest practical extent. Required field work shall be minimized.
6.1.2 Quality assurance, quality control, and inspection requirements as defined in 4WGN-20001 shall be adhered to.
6.2 Layout
6.2.1 Skid layout shall provide access to all manual valves and control valves by locating them either on the skid perimeter or by providing an access aisle on the skid. Access aisles shall be 760 mm (30 in) wide minimum. Extension handles and chain wheels are acceptable.
6.2.2 Piping, conduit, and tubing shall not cross skid walkways, which might result in a tripping hazard.
6.2.3 Skid layout shall provide space for removal of routine maintenance items such as heat exchanger bundles, pump motors, pumps, and filter elements.
6.2.4 Diagonal bracing of vertical steel members is not permitted when it limits personnel access to equipment, valves, or instruments.
6.2.5 Field tie-in points for instrumentation and wiring shall be centrally located at or along the skid perimeter. Field tie-in locations for piping will be defined in the equipment specification.
6.3 Design Pressure
6.3.1 Design pressures shall be a minimum of 10% greater than the maximum operating pressure.
6.3.2 Equipment in steam service shall be designed for full vacuum.
6.3.3 Equipment that might experience a partial vacuum, during either normal operation or upset conditions, shall be designed for full vacuum.
6.3.4 The number of individual pressure circuits and relief valves shall be kept to a minimum.
6.4 Design Temperature
6.4.1 Design metal temperatures shall be a minimum of 28C (50F) above the maximum operating temperature.
6.4.2 Minimum design metal temperature will be defined in the equipment specification.
6.5 Noise
6.5.1 The maximum sound level shall not exceed 85 dBA measured 4570 mm (15 ft) from the sound source during start-up, normal operation, and shutdown.
6.6 Packaged process systems, including structural steel, equipment, and piping shall be designed according to the Uniform Building Code. Site-specific loads will be defined in the equipment specification.
6.7 All equipment and commodity items purchased by the supplier shall be obtained from subsuppliers approved by Air Products.
- MATERIALS OF CONSTRUCTION—GENERAL
7.1 Unless otherwise noted, a 1.6 mm (1/16 in) corrosion allowance shall be provided on carbon steel and low alloy steel equipment. Corrosion allowance on piping is defined in the applicable piping specifications. No corrosion allowance shall be provided on stainless steel.
- ROTATING EQUIPMENT
8.1 Equipment includes, but is not limited to, pumps, fans and blowers.
8.2 Pumps shall be furnished with the following (see also specific equipment specifications):
- Suction and discharge block valves and a discharge check valve.
- A 1/2 inch NPT pressure tap with steel plug shall be provided in the suction piping.
- A temporary suction strainer. Strainer shall be conical type, Mack Iron Works StylePCL with 200% open area and 3 mm (1/8 in) diameter holes in accordance with 4WPI-FWZM04. Wire mesh size shall be accordance with 4WPI-PW45001.
- Piping rated for the shutoff head at maximum suction pressure or discharge piping provided with an appropriate over-pressure device.
8.3 All rotating equipment shall be furnished with the following:
- Non-groutable baseplates.
- Baseplate leveling screws M20 (3/4 in) minimum.
- PRESSURE VESSELS
9.1 Pressure vessels shall be designed and fabricated according to 4WEQ-1010.
9.2 Manway size shall be 500 mm (20 in) minimum as standard.
9.3 Process nozzles shall be flanged when vessel entry is possible.
9.4 Tanks falling outside the scope of ASME BPVC, Section VIII, Div. 1 shall be designed and fabricated in accordance with AWS D1.1.
- SHELL AND TUBE HEAT EXCHANGERS
10.1 Heat exchanger design and construction shall be according to 4WEQ-1430.
10.2 Heat exchangers in cooling water service shall have the cooling water on the tubeside, whenever practical.
10.3 Heat exchangers with cooling water on the shellside shall have removable tube bundles.
10.4 Fixed tubesheet exchangers and their related control systems shall be designed considering start-up, shutdown, and upset conditions.
- INSTRUMENTATION AND PROCESS CONTROLS
11.1 General
11.1.1 All instruments shall be easily accessible for maintenance and calibration. Indicators shall be oriented for easy, unobstucted viewing.
11.1.2 Instrument installation shall generally follow API RP 550.
11.1.3 Instrumentation shall meet the requirement of the NEC where applicable.
11.1.4 All instrument tubing and wiring that must leave a skid shall be brought to a separate bulkhead panel for tubing, and separate junction boxes for each type wire (e.g., 120 VAC, dc). All bulkhead panels and junction boxes shall be located on the perimeter of the skid.
11.1.5 The size and type of connections required for piping and vessel instrumentation shall be standardized.
11.1.6 The use of plastic for pressure-containing devices [equipment exposed to pressure of 1.0 bar g (15 psig)] shall be avoided. If for some reason a plastic pressure-containing device needs to be used, the following approval process must be followed:
- Verify that there are no other acceptable metallic solutions.
- Obtain test data showing acceptable accelerated aging with UV or any other environmental condition (e.g., ozone, sulfur, chlorides) for the life of the facility (typically 15 years).
- Document the pressure rating of the device.
- Determine if additional environmental protection is required.
- Review the above with Air Products and request a written approval. Devices may only be used with written approval from Air Products.
The use of plastic pressure-containing parts is not allowed in indoor locations or in panels/boxes without adhering to the approval process listed above.
11.2 Wiring
11.2.1 Wiring shall be according to 4AEL-620305 and the standard details shown in STD-P306A, STD-P308A, STD-P310A, and STD-P314A.
11.2.2 Electrical supply for instrumentation shall be 120V, 60 Hz, single phase ac with grounded neutral or as modified in the equipment specification.
11.2.3 Electronic instruments shall be nominal 24 Vdc, two-wire type. Dc power will be supplied by others.
11.2.4 Instrument wiring shall be Dekoron-type, twisted, shielded stranded pairs of #18 AWG minimum wire. Each pair of wires shall be terminated on three terminals: positive, negative, and shield.
11.2.5 Thermocouple wiring, dc signals, and ac current lines shall not be run in the same conduit. Conduits shall be spaced a minimum of 305 mm (12 in) apart and shall intersect when necessary at right angles.
11.3 Tubing
11.3.1 Instrument tubing shall be according to 4APS-630290S. Tubing material will be specified in the equipment specification.
11.3.2 Plastic Instrument air tubing may be used if it has been approved by Air Products in writing and is clearly marked as suitable for outdoors and UV protected or installed inside a panel or box and will not be subjected to UV light. Plastic tube fittings are not permitted.
11.3.3 Tubing in which moisture can condense shall be free draining. When this is not practical, condensate traps shall be provided at all low points.
11.3.4 Process tubing shall meet the following requirements:
All process tubing to a pressure-measuring instrument shall include a two-valve manifold installed between the process root valve and the instrument and shall be located at the instrument unless the instrument is close-coupled to the process piping.
Differential pressure instruments shall include a three-valve manifold for pressures up to and including 40 bar g (600 psig) and five-valve manifold for pressures exceeding 40 bar g (600 psig). Toxic fluids require five-valve manifolds regardless of pressure.
Unless impractical, instruments in steam service shall be installed above the tap. If the instrument must be located below the tap, a fill tee shall be provided in the tubing.
Instruments in liquid service shall be installed below the tap, with the tubing sloping toward the instrument.
Siphons shall be used for pressure measurement in steam service.
Condensing legs shall be used for flow measurement in steam service.
11.3.5 Pneumatic tubing shall meet the following requirements:
For instruments with pneumatic signal outputs, a tee and plug shall be installed in the tubing, adjacent to the instrument.
When a single pneumatic signal is controlling two or more process variables, an isolating block valve shall be installed on each circuit.
11.4 Control Valves
11.4.1 Control valve sizing shall be according to the Instrumentation, Systems, and Automation Society (ISA) 75.01.01.
11.4.2 Control valves shall have a wide open Cv approximately twice that calculated for normal process conditions, and not less than 1.05 times maximum conditions, unless process considerations require a different value.
11.4.3 Control valves shall have, as a minimum, steel bodies and stainless steel trim.
11.4.4 Whenever the pressure drop across a control valve exceeds 10.3 bar (150 psi), hardened trim such as Stellite shall be used.
11.4.5 Butterfly and ball valves may be used, subject to Air Products’ approval, when the pressure drop is low and high capacity is required.
11.5 Temperature Sensors and Indicators
11.5.1 All process temperature sensors (RTD and thermocouple type) and indicators (bimetallic or filled types) require thermowells. Thermowells shall be provided according to 3PS15002. Piping may need to be increased in size to accommodate thermowells. Minimum thermowell connection size shall be 3/4″.
11.5.2 Duplex-type thermocouples and RTDs shall have both sensors wired to the skid thermocouple junction box.
11.6 Instrument air piping shall be supplied according to 4API-630292.
11.7 All pneumatic instruments shall have an individual filter regulator installed in the instrument-air supply tubing unless already furnished with the instrument. Filter regulators must have metal bowls and caps.
11.8 All transmitters shall be fitted with a local indicator.
- PRESSURE RELIEF DEVICES
12.1 Pressure relief devices shall be provided according to 4WPI-EW80010.
12.2 Pressure relief devices 50 mm (2 in) and larger shall be flanged; 37 mm (1 1/2 in) and smaller shall be threaded.
12.3 Pressure relief valves shall have carbon steel bodies and stainless steel trim, as a minimum, with additional requirements as necessary for the particular service conditions.
- ELECTRICAL
13.1 All electrical equipment shall be provided and installed according to 4AEL-620302 and 4AEL-620305.
13.2 Electric motors shall meet the requirements of 4WEL-52312.
13.3 All 120V wiring shall be completely shop installed. Wiring shall be run in rigid, galvanized conduit to a junction box at the battery limits of the skid. Individual neutrals shall be provided and wired from all control devices, such as 110 VAC solenoids, to terminals in the junction boxes.
13.4 A grounding system shall be provided.
13.5 Motors will be grounded at the Motor Control Center (MCC) by others.
13.6 Any electrical equipment other than 480V motors requires additional requirements to be specified by the Air Products Electrical Engineering Group.
- PIPING
14.1 General
14.1.1 Piping design and fabrication shall be according to ASME B31.3 and 4WCE-670200.
14.1.2 The following portions of 4WCE-670200 are not applicable:
- References to 670.219
- Underground piping requirements
14.1.3 Piping on each skid shall be completely shop installed.
14.1.4 Piping shall not be located below the top of the skid deck.
14.1.5 Off-skid piping DN65 (NPS 2 1/2) and larger shall be furnished loose, as welded spool-pieces. These spool pieces shall be fabricated as completely as possible, leaving an allowance in three planes for field adjustment.
14.1.6 Off-skid piping DN50 (NPS 2) and smaller shall be furnished in random lengths with the necessary pipe fittings.
14.1.7 A piping flexibility analysis is required for all hot [>121C (250°F)] and/or large bore [>DN200 (NPS 8)] piping.
14.1.8 Piping reactions at vessels and heat exchangers shall be evaluated according to WRC Bulletin 107.
14.1.9 Expansion joints and flexible hoses are not permitted. Dresser and Victaulic couplings will be accepted on a case-by-case basis.
14.1.10 A spectacle blind shall be provided at all flanged vessel connections to process piping, to isolate any vessel having a manway.
14.1.11 The supplier shall design and furnish all required pipe supports located off the skids for field installation by others. Foundation loads exerted by these pipe supports shall also be provided.
14.1.12 Piping terminations at skid battery limits shall be designed as anchor points. The supplier shall design, furnish, and install all piping supports and perform pipe stress analysis to these points. Exceptions, due to instances of large bore pipe, vessel connections close to the edge of the skid, and/or space limitations, will be evaluated on a case-by-case basis.
14.2 Instrument Connections and Piping
14.2.1 All instruments in service above 6.9 bar g (100 psig) shall have block and bleed valves for instrument removal and replacement. Valves shall be 12 mm (1/2 in) barstock needle valves or globe valves.
14.2.2 Instrument connections DN25 (NPS 1) and smaller shall be screwed couplings. Larger connections shall be flanged.
14.2.3 A thermometer with thermowell shall be provided in the shellside and tubeside outlet piping downstream of all heat exchangers.
14.2.4 Piping adjacent to flow elements shall meet the requirements of ISO-5167-1 per the accuracy needs of the measurement.
14.3 Manual Valves
14.3.1 Manual valves shall be rated for the maximum service temperature and pressure. Manual valves operating above 260C (500F) shall be either gate or globe valves with outside screw and yoke, and 11 1/2 to 13% Cr seat and disc.
14.3.2 Double block and bleed valves shall be provided at all control valves.
14.3.3 All manual valves shall have stainless steel trim.
14.3.4 Globe valves shall be used for control valve bypasses.
14.4 Vents and Drains
14.4.1 All low points and high points in water, steam, and condensate service shall be provided with drain and vent connections, respectively. These connections shall be furnished with valves.
14.4.2 Steam traps shall be provided with strainers and blowdowns.
14.4.3 Any section of piping that can be blocked-in between valves shall be provided with a vent that is equipped with a valve.
- STRUCTURAL STEEL
15.1 Structural steel design and construction shall be in accordance with the AISC “Specification for Structural Steel Buildings, Allowable Stress Design.”
15.2 Structural steel shall be provided according to 4ACS-640130, 4ACS-640131, and 4ACS-640132.
15.3 Equipment and piping supports shall be designed for weight full of water. Design loads shall also include the weight of insulation, when applicable.
15.4 Structural Steel Layout
15.4.1 Skidded systems and module structure steel shall be designed so that when grouted to their foundation, water and debris is not trapped. To this end, structural steel shall consist of a system of longitudinal and transverse members. The skidded system or module shall be designed to be supported on the foundation by grouting of the transverse members only.
15.4.2 Transverse member spacing shall be maximum 4 m (12 ft) on centers for rotating equipment applications
15.4.3 Rotating equipment shaft centerlines shall be parallel with the longitudinal members.
15.4.4 Rotating equipment baseplates shall be supported by longitudinal members tied to transverse members. In addition, the longitudinal members shall be crossbraced with full size structural members at each end of the equipment baseplate. For rotating equipment with drivers 200 kW (250 hp) or above, an additional crossmember at the middle of the baseplate shall be provided.
15.4.5 The skidded system or module structure steel shall be provided with two minimum m30 (1-1/4 in) leveling screws at the end of each transverse support member. The leveling screws shall be located in the longitudinal members, 150 mm (6 in) from the transverse member to facilitate the placement of grout forms in the field. The leveling screws shall be provided with jack pads minimum 75 mm (3 in) in diameter for each leveling screw. Minimum pad thickness shall be 13 mm (1/2 in
15.4.6 Supplier shall demonstrate to the Purchaser the levelness of the skid or support mounting surfaces. Levelness shall not exceed +/- 3 mm (1/8”) total, based on starting at one anchor point and proceeding to all others
15.4.7 In addition, rotating equipment shall be level within .25 mm/m (.003 in/ft).
15.4.8 For rotating equipment applications with power less than 200 kW (250 hp), equipment baseplates shall be shall be bolted to module steel and gaps checked at each anchor bolt location prior to torquing. Gaps in excess of 1.0 mm (.030”) shall be shimmed with a solid stainless steel shim.
15.4.9 For rotating equipment applications with power greater than or equal to 200 kW (250 hp) baseplates shall be mounted on adjustable chocks, at each anchor bolt location, after leveling with leveling screws. Supplier shall furnish the chocks from Vibracon or approved equal. Information (technical & ordering) on Vibracon can be found at www.vibracon.com or from the following.
Machinery Support, Inc. or Causeway Machinery Ltd.
109B 86th Street 70 Pier Road
Virginia Beach, VA 23451 Erith, Kent DA8 1TA
(877) 621-1777 Toll Free United Kingdom
(757) 417-7411 +44-1322-346346
15.5 Ladders, Platforms, and Stairs
15.5.1 Platforms with ladders shall be provided at all manways, and remotely located manual valves and instruments when routine access is required for start-up, normal operation, and shutdown.
15.5.2 Ladders, platforms, and stairs shall be provided according to drawings 309710D, 309711D, and 309712D, and OSHA requirements.
15.5.3 Ladders and platforms shall be trial fit before shipment.
15.6 All lifting attachments shall be designed based on 1 1/2 times the dead load. Maximum stresses shall not exceed the normal allowable stresses.
15.7 Skid decking shall be walkway grating, or as otherwise defined in the equipment specification.
15.8 All fillet-welded attachments shall be completely seal welded.
15.9 Structural steel shall be designed to account for dead, live, wind, seismic, thermal, and shipping loads in combinations consistent with the appropriate design codes.
15.10 Vertical deflections shall not exceed L/240.
15.11 Galvanized grating, joined with stainless steel clips, shall be used in areas where access for operation or maintenance is required. The grating shall be designed for easy removal to facilitate access for grouting of the transverse members.
- INSULATION AND HEAT TRACING
16.1 Insulation shall be required on all piping and equipment that normally operates above 65C
(150F) or below 10C (50F).
16.2 Unless otherwise defined in the equipment specification, all insulation will be furnished and field installed by others. The supplier’s design, however, shall provide adequate clearances and be otherwise compatible with the insulation requirements outlined below.
16.3 Space allowance for insulation shall be based on the heat conservation requirements defined in 3PI99001, Table 2.
16.4 Vertical vessels requiring insulation shall be equipped with insulation supports in accordance with 4WEQ-1020. Horizontal vessels and heat exchangers do not require insulation supports. Insulation thicknesses shall be based on 3PI99001, Table 2.
16.5 Heat tracing requirements with the related Air Products specifications and standards will be defined in the equipment specification.
16.6 Project-specific insulation requirements will be defined in the equipment specification if applicable.
- PRESSURE TESTING
17.1 The ASME B31.3 piping code pressure tests shall be performed before painting.
17.2 Water used for pressure testing shall be potable. Chloride content shall be less than 50 parts per million (ppm) when stainless steel components will be tested.
17.3 Pneumatic testing shall be done using dry, oil-free air or nitrogen. Compressed air shall be passed through a silica gel or activated alumina drier, an oil coalescer, and a filter before entering the system to be tested. Dew point shall be -40C (-40F) or lower.
- PAINTING AND INTERNAL CLEANING
18.1 Platforms, ladders and cages, stairs, handrails, and grating shall be galvanized.
18.2 Galvanized and stainless steel surfaces shall not be painted.
18.3 All uninsulated carbon steel equipment, skids, structural steel, and piping shall have surface preparation, prime, and finish painting according to 4WEQ-6804.
18.4 All insulated piping and equipment shall have surface preparation and painting only as required by the equipment specification and according to 4WEQ-6804.
- Process-specific internal cleaning requirements will be defined in the equipment specification.
- The underside surfaces of the transverse members in contact with grout shall be prime paint coated only to facilitate adhesion with the grout.
- SHIPPING
19.1 All skid components and equipment shall be designed for shipping loads as follows:
| Condition | Load Direction | Load |
| 1 | Up | 0.5W |
| 2 | Down | 0.5W |
| 3 | Axial | 1.5W |
| 4 | Lateral | 0.5W |
19.2 The foregoing loads are given in terms of the static dead load, W, acting downward, and are additive to the static dead load.
19.3 Maximum stress for any of the above conditions shall not exceed the normal allowable design stress.
19.4 All temporary shipping supports shall be clearly identified by painting them a readily noticed color such as red or orange, and by tagging them with written instructions for removal at site prior to operation.
19.5 All equipment, piping, and tubing likely to vibrate during shipment shall be braced to prevent damage during shipment. Items that cannot be adequately braced (e.g., delicate instruments) shall be removed, packaged, and shipped separately.
- ENGINEERING DELIVERABLES AND DOCUMENTATION
20.1 Supplier drawings and other documents shall be submitted according to the VDR Set for “Packaged Process Systems” included with the purchase order. This form will be supplemented by additional VDR Sets for specific items such as pressure vessels, pumps, and heat exchangers as required, and as defined in the equipment specification.
20.2 The expected content and format of engineering deliverables are clarified below.
20.2.1 The Process Flow Diagram (PFD) shall include the following:
- All process equipment with item numbers.
- Heat and material balance point numbers (a minimum of one heat and material balance point is required upstream and downstream of each piece of process equipment).
- Basic control strategy showing control valve locations, type, and sensing locations.
- Circuit design pressures.
- Utility use points (for example, cooling water, and steam).
- Major process line sizes.
20.2.2 The Heat and Material Balance shall include the following:
- Design case and any alternate operating cases required, listing all balance points designated on the PFD.
- Data for all process, steam, and utility streams.
- Description of normal process excursions, specifying cause, temperatures, pressures, and flow rates.
- Guaranteed rates.
- Safe upper and lower limits for temperatures, pressures, and flows.
20.2.3 The Utility Summary shall include the following:
- Required quantity, pressure, and temperature of each fluid.
- Power consumption.
- Make-up fluid requirements.
- Guaranteed maximum quantity of each utility required.
20.2.4 Piping and Instrument Diagram (P&ID)
- P&IDs shall be prepared using standard Instrumentation, Systems, and Automation Society (ISA) symbols.
- The supplier shall provide the information and assistance required for Air Products to generate a table of critical safety systems, included in the P&ID. This table lists the following information for each critical safety system:
– Protected hazard (for example, overfill, and overpressure)
– Purpose of equipment (shutdown function)
– Instrument tag number
– P&ID sheet number
– Proof test frequency
– Proof test task number
– Shutdown/alarm set points
- The following information shall be shown on the P&ID:
– All equipment with equipment numbers
– All process lines and process valves
– Valve failure directions
– All control loops
– All critical elevations
– Heat and material balance points
– All process vents and drains
– Line sizes and line numbers
– Line specification numbers
– Insulation specifications and thicknesses
– All feed and utility system tie-in points
– All in-line instruments and devices
– Safety valves
– Scope of supply breaks
– Interlocks, computer signals, control and shutdown logic (or reference to instrument bubble diagrams)
– Heat tracing requirements
20.2.5 The Line List shall include the following information as a minimum:
- Line number
– The line number shall change when a line begins or terminates at a piece of equipment; changes piping specification; or branches, regardless of size.
– The line number shall identify the pipe size, service fluid, piping specification number, and line identification number.
- Line size
- P&ID sheet number(s) on which the line is shown
- Piping specification
- Wall thickness, if not defined in the piping specification
- Location (From and To)
- Intermittent service (Yes/No)
- Normal and maximum operating pressures and temperatures
- Design pressure and temperature
- Insulation, heat tracing, and painting requirements (I,H,P)
- Postweld heat treatment requirements (Yes/No)
20.2.6 The Plot Plan for the system shall include the following:
- Anchor bolt sizes and locations
- Piping tie-in locations and connection details
20.2.7 Electrical schematics shall include written start-up and shutdown philosophy.
20.2.8 Electrical physicals shall include junction box connection drawings
20.2.9 The valve summary for all manual valves and check valves shall be in numerical order.
20.2.10 Instrumentation and Process Controls
- Installation drawings, including physicals, shall show all required signal and control wiring brought to the main control room.
- All process controls and instrumentation information shall be submitted in electronic format such as DBase, AutoCad, Word for Windows, or Excel for Windows.
- Instrument specification sheets shall be provided for all instruments, control valves, pressure relief devices, transmitters, positioners, recorders, indicators, and solenoids.
- Instrument specification sheets shall include a complete description of the process conditions, necessary turndown, measurement ranges, and scale ranges for all instruments.
- Instrument specifications shall include manufacturer, model, materials of wetted parts, part number, zero and span calibration setting, and alarm set points.
20.2.11 Vent/Flare Summary
- The supplier shall provide a flow rate summary for all control valves, safety valves, and vents that discharge into a vent or flare header for start-up, normal operating, emergency, and valve failure cases.
- The supplier shall provide a flow rate summary for all control valves, safety valves, and vents that discharge to atmosphere for start-up, normal operating, emergency, and valve failure cases.
20.2.12 Safety Relief Device Summary
- The supplier shall provide a Safety Relief Device (SRD) summary listing the following information:
– SRD tag number
– SRD size, inlet/outlet
– Orifice size
– Manufacturer’s name and model number
– Type of lifting device (plain lever, packed lever, none)
– Set pressure
– SRD type (pressure or thermal relief device)
– P&ID sheet number where SRD is shown
– Location (equipment tag or piping line number)
– Service (fluid normally seated against the closed SRD)
- The supplier shall provide the supporting calculations for relief device sizing. These shall include calculations for all possible overpressure events, including the governing case.
20.2.13 As-built drawings shall indicate the actual location of all field tie-in-points for piping and anchor bolts.
20.2.14 Shipping and lifting drawings shall include the following information:
Shipping envelope size
Shipping weight
Location of attachments for lifting and tie-down
Details of lifting and tie-down attachments
Reaction forces at shipping supports and tie-downs
Location of center of gravity
Recommended rigging arrangement for lifting
20.2.15 Manuals
The supplier shall provide all drawings, manuals, and instructions necessary for construction, operation, and maintenance.
The supplier shall provide detailed written start-up procedures, normal operating and shutdown procedures, and emergency shutdown procedures with step-by-step instructions that reference specific valve and instrument tag numbers. Valves and instruments shall also be identified by process and function.
Written operating procedures shall include the following information:
– Initial start-up of the system.
– Normal operating procedures, including start-up and shutdown.
– Procedures for temporarily operating under other than normal conditions, if applicable.
– Emergency shutdown procedures, including conditions which require shutdown.
– Consequences of a deviation from normal operating limits.
– Steps to avoid or correct a deviation from normal operating conditions.
– Properties of and hazards presented by chemicals used in the process, including Material Safety Data Sheets (MSDSs).
– Precautions necessary to prevent exposure to chemicals, including engineering controls, administrative controls, and personal protective equipment required.
– Measures to take if physical contact or airborne exposure occurs.
– Quality control for raw materials and control of hazardous chemical inventory levels.
– Safety systems and their functions.
- TAGGING
21.1 Every instrument, control valve, and manual valve shall be furnished with a stainless steel identification tag, with the tag number permanently engraved or stamped on it. Identification tags shall be attached with stainless steel wire.
21.2 Identification tags for all instruments shall be stamped with the tag number, purchase order number, and project number.
21.3 Valve tags shall be attached to valve bonnets or bodies, not to handwheels or levers.
Appendix A
Flammable/Toxic Gas Service
The following requirements supplement those in the body of this specification when the packaged process system is in flammable or toxic gas service.
Caution: Plastic components typically have low melting points and are not suitable in flammable gas plants in pressure-containment service. Plastic parts may never be used to contain pressurized flammable materials.
A1. RELATED DOCUMENTS
A1.1 Air Products Engineering Documents
4WEQ-1051 Welding of HyCO Plant Equipment
4WCE-670200 Specification for Process Piping
4WEQ-1105 HyCO Plant Positive Material Identification (PMI) Requirements
4AEL-620301 Hazardous Area Requirements
STD-P309A Electrical Standard-Conduit Connection to Field Devices-Class 1 Hazardous Areas
A2. PRESSURE VESSELS AND HEAT EXCHANGERS
A2.1 The supplier shall calculate the maximum allowable working pressure (MAWP) of pressure vessels and heat exchangers at design temperature, based on the as-built material thicknesses. These values shall be stamped on the nameplate. These values and the governing components shall be listed on the vessel or heat exchanger general arrangement drawing. Nozzle reinforcement shall not limit MAWP. Code hydrostatic test pressures shall be based on the calculated MAWPs.
A2.2 Instrument nozzles shall be flanged.
A2.3 Tube-to-tubesheet joints shall be seal-welded and roller-expanded into tube holes having two grooves. Tube-to-tubesheet welds shall be strength welds when required by 4WEQ-1430
A2.4 Welding shall meet the requirements of 4WEQ-1051.
A3. INSTRUMENTATION AND PROCESS CONTROLS
A3.1 Instrument lines shall be all-welded construction up to the block valve. The instrument side of the block valve and the instrument shall be threaded to permit instrument removal.
A4. PIPING
A4.1 Welded connections shall be used whenever possible for joining piping, valves, and equipment. Flanged connections shall be used only when required for maintenance.
A4.2 Manual vent and drain valves shall be welded on the process side. The downstream or atmospheric side shall be threaded and provided with a steel plug or cap.
A4.3 All check or block-type bleed valves shall terminate with a screwed end and shall be fitted with a steel plug.
A4.4 All in-line valves with welded ends shall have removable seats that can be replaced with the valve body remaining in place.
A4.5 Welding shall meet the requirements of 4WEQ-1051.
A4.6 PMI shall be performed in accordance with 4WEQ-1105.
Appendix A (continued)
A5. ELECTRICAL
A5.1 All electrical equipment shall be provided and installed in accordance with 4AEL-620301, in addition to the base requirements of 4AEL-620302 and 4AEL-620305.
A6. OTHER
A6.1 Requirements in the following areas will be defined in the equipment specification:
Hardness testing after postweld heat treatment
Special assembly procedures for large or custom designed flanges
A7. ENGINEERING DELIVERABLES AND DOCUMENTATION
A7.1 Postweld heat treatment time/temperature charts. These shall be traceable to each piece of equipment and pipe spool that was postweld heat treated.