IPE-TM-300 Vessels
Guidelines for Schedule A Revamps of Vessels
IPE-TM-300-12
1. Purpose
This procedure provides guidelines for the consistent preparation of Project Specification 301 Vessels for Schedule A revamps.
2. General
Use the guidelines established in this procedure unless the customer specifies other requirements.
Technical requirements and procedures for revamps of specific vessels are not included in this procedure. They are determined by each technology center.
3. Project Specifications
The following project specifications may be issued for Schedule A revamps:
- 301 - Vessels – This specification is issued if vessels are part of the Schedule A revamp. Use general project specification template “301 Revamp.doc” from the document system with this procedure for a new Project Specification 301. Follow the format shown in Attachment 1.
- 307 - Trays and Packing – This specification is issued if trays and packing are part of the Schedule A revamp. Create this specification using general project specification template “307.doc” from the document system with the guidelines for a new Project Specification 307. Follow the format shown in Attachment 2. Only new or modified internals should be listed.
Add project specific notes, as required, to the specification templates.
Attachment 1 contains examples of 301 specifications for Schedule A revamp vessels.
- Related Project Specifications
Related project specifications may also be required and shall be the same as for a new Schedule A design.
5. Existing Vessels
List vessels requiring no modification in the 301 Project Specification “Table 1: Existing Vessels” (see 301 template referenced in section 3 above). Provide sectional elevation data sheets in the 301 project specification for existing vessels requiring modification, including rerating.
See Attachment 1 for examples of a 301 project specification and elevation data sheets.
6. Vessel Revamp Notes
The following notes are required in the Revamp 301 project specification and are included in the 301 Revamp template:
- Customer/Contractor shall verify that the structural and mechanical condition of the existing vessel(s) are satisfactory for continuing operation at the revamp design conditions and under original applicable codes and practices. Customer/Contractor shall also verify that the vessel support and foundation are satisfactory for continuing operation at the revamp design conditions and under current applicable codes and practices.
- Customer/Contractor to verify existing dimensions in field.
- Nozzles not listed in the nozzle designation table are not required by Inflection Point Engineering and have not been reviewed.
For existing vessels where fabrication drawings do not state a vacuum condition, a vacuum design note is to be referenced in the specification because a vacuum condition can occur if the vapor pressure falls below atmospheric pressure during cool down (see 301 template referenced in Section 3 above).
7. Design Data
For all modified Schedule A revamp vessels (see Attachments 1 for examples) include the following conditions on the vessel elevation sheets:
- Revamp internal and external design temperature and pressure.
- Revamp maximum operating temperature
- Revamp or existing minimum design metal temperature(MDMT), whichever is lower.
For all existing Schedule A revamp vessels which are not modified, include only the requested conditions in Table 1 of the 301 template referenced in Section 3 above.
For all existing vessels whether requiring modifications or none at all, an “as-built” drawing must be referenced for each vessel on either the elevation sheet or in Table 1.
When modifying or welding to the shell, reference Inflection Point Engineering Standard Specifications 3-11, 3-12, 3-13, 3-15 or 3-17 based on shell material or use of ASME Section VIII, Division 2. When only replacing internals not welded to the shell, a Inflection Point Engineering standard specification reference is not required.
8. Metallurgy
Prior to any vessel modification planning, the metallurgy specialist shall confirm that the existing vessel metallurgy, as stated in the fabricator’s “as-built” drawings, is acceptable at the revamp design conditions and service.
9. Re-Rating
Existing vessels shall be re-rated if either the revamp design pressure or design temperature exceeds the existing design pressure or design temperature, or if the revamp MDMT is lower than the existing MDMT. The vessel may also need to be re-rated based upon inspection. For any changes to existing design conditions, a note should be included on the spec sheet as such: “Vessel shall be rerated based on new design conditions shown”.
10. Nozzles
The following applies to all modified vessel specification drawings requiring Revamp modifications to nozzles:
- Show new or modified nozzles, existing main process line nozzles (e.g., inlet, outlet) and existing manways on the vessel drawing.
- In the vessel drawing, show nozzle mark letters for only new or modified nozzles. For modified nozzles, use the vessel fabricator’s nozzle marks.
- In the nozzle designation table of the vessel drawing, list the nozzle marks, number, size and service name of new or modified nozzles. List only the number, size and service name of all other nozzles required by Inflection Point Engineering Revamp in the nozzle designation table. The Design Engineer shall inform the Vessel Drafter which nozzles are required by Inflection Point Engineering. The unmodified nozzles are included in the table only for reference during the P&ID review.
11. Drawing Presentation
Vessel modifications are typically shown on a sectional elevation drawing. Existing shell, nozzles and internals are to be shown as phantom line style. New or modified components are to be shown as solid line style. See Attachment 1 for examples. Drawing shall clearly convey modification requirements while avoiding unnecessary “existing” equipment detail otherwise found on “As-built” drawings.
12. New Equipment
Show new vessels and internals per new Schedule A specification format and requirements.
13. Design Engineer Responsibilities
The Design Engineer shall obtain the following information from the customer prior to Inflection Point Engineering starting the revamp work:
- Fabricator’s “As-Built” general arrangement drawings of vessels.
- Latest inspection reports (if available).
- “As-Built” fractionator tray/packed bed assembly drawings (as necessary).
The Design Engineer shall provide the following information to the Vessel Drafter prior to the start of drafting work:
- Information obtained from the customer, listed above
- Original Inflection Point Engineering project specifications and drawings
- Revamp data sheet including design conditions.
- A completed 112 Revamp spec for the Revamp project showing Vessel item numbers and each vessel status.
- A list or marked fabrication drawing showing required nozzles for Inflection Point Engineering revamp (including number, size and service name) for each modified vessel.
- Revamp process data sheets for column internals
- Revamp project number
- Fractionator summary sheet (as necessary)
- Summary of required vessel modifications, including a sketch when applicable
14. Calculations
See Procedure Section 4 Calculations.
15. Checklists
Design Preparation Procedure/Checklists PSD-40 is to be completed by Design Engineer as required for all new vessels.
16. Vessel Drafter Responsibilities
The Vessel Drafter shall create vessel specification 301 and 307 using data provided by Design Engineer in section 13 above. Specifications will be prepared and completed using the Vessel Work Process 2069-02 and templates or attachments referenced within this document.
Attachments
IPE-TM-300-12-Vessel Attachment 1 Reference 1-4.pdf
PDF attachment · 2.2 MB · 4 pages
IPE-TM-300-12_Attachment_2 - Trays&Packing Ref
Inflection Point Engineering XYZ Process Unit (Revamp)
| Item Number | Service | Sheet |
|---|---|---|
| General Notes | 2 & 3 | |
| V-2203 | Recycle Compressor Suction Drum | 4 |
| V-2205 | Stripper | 5 |
| Tray Data | 6 | |
| V-2510 | Stabilizer | 7 |
| Tray Data | 8 | |
The following general notes apply to all items listed on individual specification sheet:
A. All items shall comply with the requirements, terms and conditions of this Project Specification and Inflection Point Engineering Standard Specification 3-18. For details of vessels see Inflection Point Engineering Project Specification 301.
B. All trays are numbered from TOP #1 TO BOTTOM.
C. Abbreviations: CS = carbon steel; KCS = killed carbon steel; Type 410 = 13% chromium alloy;
Type 304 = 18% chromium -8% nickel alloy; Type 316 = 16% chromium – 12% nickel alloy; "M.R." or "MR" = manufacturer's and / or contractor's responsibility. SS may be any of the following – Type 410, Type 304 or Type 316. See Inflection Point Engineering Standard Specification 3-18 for additional clarification on materials.
D. When system of measurement is metric, all dimensions are in millimeters except as noted.
E. For vessels where the inside diameter is indicated to be minimum (min), adjustments in tray dimensions to accommodate the final inside diameter selected shall be to the chord height of side downcomers which are also indicated as minimum (min).
F. Vessel nozzle and internals orientation errors are a common source of problems for trayed columns. Inflection Point Engineering does not supply specific orientation drawings in order to allow flexibility to the contractor, the vessel fabricator and the internals supplier. The contractor is to ensure sufficient communication between the various parties to avoid orientation difficulties. Some common orientation restrictions follow.
- Thermowells that are inserted into trayed distillation columns must not contact internals such as support rings or downcomer panels.
- Reboiler return nozzles should be oriented to minimize vapor interaction with the liquid from the bottom tray traps.
- Adjacent distillation column trayed sections normally have specific orientation requirements to facilitate vapor and liquid movement between the sections. The supplier of the vessel internals (trays and packing) must provide the vessel fabricator with orientation drawings.
- Nozzles shall not be located in downcomers.
The following notes apply only when listed for individual item of specification sheet:
1. One pass.
2. Two pass, center downcomers.
2x. Two pass, side downcomers.
3. Three pass.
4. Four pass, intermediate downcomers.
4x. Four pass, side and center downcomers.
5. Tray(s) shall be liquid tight by seal welding, except at manway(s) where gasketing shall be used.
6. Tray(s) including downcomer(s) shall be liquid tight by seal welding, except at manway(s) where gasketing shall be used.
7. Do not provide drain holes. Tray(s) shall be liquid tight.
8. Stiffeners and support members transverse to the liquid flow direction shall not exceed 2" (50 mm) in depth and shall not be located above upcomers, or within a lateral distance from upcomers equal to one tray space.
9. Trays shall be assembled on rods and spacers or arranged in cartridges with trap attached to downcomer of bottom tray. Furnish Teflon or metal wall wiper at each tray for liquid seal.
10. All tray assemblies shall be designed for installation and removal from top and bottom.
11. Each tray shall have froth initiator(s) in accordance with Inflection Point Engineering Standard Drawing No 3-130.
12. Bubble caps shall be in accordance with Inflection Point Engineering Standard Drawing No Type No .
13. Ceramic Fiber gasketing shall be used as required for proper design and installation of tray(s), manway(s) and / or distributors for packed beds.
14. Each tray shall have a total of - diameter holes on approximately square, equilateral triangular pitch.
15. Each tray shall be designed for an upward pressure differential of .
16. Drawoff well(s) on tray No shall be deep and a minimum of wide and extend under entire downcomer area.
17. Provide an additional percent of the required random packing to cover losses.
18. Minimum thickness of tray components is 12 gauge (0.104" / 2.6 mm). A corrosion allowance is not required.
19. Bolts and nuts for trays shall be carbon steel (ASTM A307 Grade A for bolts and A563 Grade A for nuts).
20. Tray No(s) shall be designed for a net uplift of 100 pounds per square foot
(488 kilograms per square meter).
Tray No(s) shall be designed for a total downward load of 100 pounds per square foot
(488 kilograms per square meter) plus dead weight.
21. Customer/Contractor must verify that the structural and mechanical condition of the existing tray(s) and/or tray supports is satisfactory for continuing operation.
22. Inflection Point Engineering MD and Slotted Sieve tray decks, downcomers, installation hardware and distributors; and Raschig Super-Rings, distributors, bed limiters, bed supports and installation hardware are to be supplied by:
Supplier (Mandatory):
Inflection Point Engineering
Telephone 716-879-7615
Facsimile 716-879-7215
| Service: Recycle Compressor Suction Drum | Service: Recycle Compressor Suction Drum | Service: Recycle Compressor Suction Drum | Service: Recycle Compressor Suction Drum | Service: Recycle Compressor Suction Drum | Service: Recycle Compressor Suction Drum | Service: Recycle Compressor Suction Drum | Item Number: V-2203 | Item Number: V-2203 | Item Number: V-2203 | Item Number: V-2203 | Item Number: V-2203 | Item Number: V-2203 |
| Notes | ||||||||||||
| Item | Quan | ID of | Material | Description | Dwg or | Dimensions | Dimensions | Dimensions | Tray | Tray | Tray | (Sheet |
| No | Assem | Vessel | Sht No | No | No | No | 2&3) | |||||
| 1 | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | Existing Trays: (Tray Data Not Required) | 21 | 21 | |
Recycle Compressor Suction Drum, Item No V-2203 (Formerly Item No P-V2203)
Original Inflection Point Engineering Project Specification 6950-307 (1988)
REFERENCE:
Customer or Vendor Dwg. No. & Revision:
KOCH Dwg. No.: 31524-B-81-1
31524-E-81
31524-E-82
31524-B-83
31524-B-84
Note(s):
| Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Item Number: C-5102 | Item Number: C-5102 | Item Number: C-5102 | Item Number: C-5102 | Item Number: C-5102 | Item Number: C-5102 |
| Notes | Notes | ||||||||||||||||
| Item | Item | Quan | Quan | ID of | ID of | Material | Material | Description | Dwg or | Dimensions | Dimensions | Dimensions | Dimensions | Tray | Tray | (Sheet | (Sheet |
| No | No | Assem | Assem | Vessel | Vessel | Sht No | No | No | 2&3) | 2&3) | |||||||
| 1 | 9 | 9 | 1700 | 1700 | CS | CS | Valve Trays | Valve Trays | 6 | 1 - 9 | |||||||
| M=* | S=* | S=* | Y= | ||||||||||||||
| 2 | 1 | 1 | 1700 | 1700 | CS | CS | Distributor Trap | Distributor Trap | 3-192 | -------- | -------- | -------- | -------- | Below | |||
| N=* | W= | W= | 9 | ||||||||||||||
| 3 | 16 | 16 | 1700 | 1700 | CS | CS | Valve Trays | Valve Trays | 6 | 10-40 | 21 | 21 | |||||
| Even | |||||||||||||||||
| 4 | 15 | 15 | 1700 | 1700 | CS | CS | Valve Trays | Valve Trays | 6 | 11 - 39 | 21 | 21 | |||||
| Odd | |||||||||||||||||
| 5 | 2 | 2 | 1700 | 1700 | CS | CS | Traps | Traps | 3-280 | N=MR, S=* | N=MR, S=* | N=MR, S=* | N=MR, S=* | Below | 21 | 21 | |
| 40 |
* See Sheet 6
Deethanizer Column, Item No C-5102 (Formerly Item No P-C5102)
Original Inflection Point Engineering Project Specification 6950-307 (1988)
REFERENCE:
Customer or Vendor Dwg. No. and Revision:
Note(s):
Tray sections shall pass through existing 24” ID vessel manway.
| Service: Deethanizer Column | Service: Deethanizer Column | Service: Deethanizer Column | Item Number: C-5102 | Item Number: C-5102 |
|---|---|---|---|---|
| Tray Data | Tray Data | |||
| Tray Identification (Tray Numbers) | TOP (1-9) | BOTTOM (10-40) | ||
| Vessel ID, mm | 1700 | 1700 | ||
| Operating Pressure, kg/cm2(g) | 12.1 | 12.3 | ||
| Operating Temperature, C | 137 | 230 | ||
| Structural Design Temperature, C | 248 | 248 | ||
| Fluid Description | HCBN | HCBN | ||
| Foam Derating Factor | 1.00 | 1.00 | ||
| Vapor -Flow Rate, kg/h | 52188 | 168934 | ||
| Density, kg/m3 | 32.87 | 41.95 | ||
| Liquid -Flow Rate, kg/h | 51320 | 384351 | ||
| Density, kg/m3 | 459.39 | 524.61 | ||
| Viscosity, cP | 0.12 | 0.13 | ||
| Surface Tension, dynes/cm | 5.5 | 4.2 | ||
| Type of Tray | Valve | Valve | ||
| For Sieve Trays | ||||
| Weir Height, M, mm | ||||
| Downcomer Clearance, N, mm | ||||
| Total Number of Holes | ||||
| Hole Diameter, mm | ||||
| Hole Area/Bubbling Area x 100 | ||||
| Tray spacing, S, mm (for exceptions see Project Specification 301 Vessels) | 600 | 680 | ||
| Notes | ||||
| Tray Layout | ||||
| Number of Passes | 1 | 2 | ||
| A, mm (minimum) | 486 | 243 | ||
| B, mm | 1214 | 485 | ||
| C, mm (minimum for 1 pass) | 486 | 244 | ||
| D, mm | ||||
| E, mm | ||||
| F, mm | ||||
| G, mm (minimum) |
| Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Item Number: V-2510 | Item Number: V-2510 | Item Number: V-2510 | Item Number: V-2510 | Item Number: V-2510 | ||
| Notes | Notes | Notes | ||||||||||||||
| Item | Item | Quan | ID of | Material | Description | Dwg or | Dimensions | Dimensions | Dimensions | Dimensions | Dimensions | Tray | Tray | (Sheet | (Sheet | (Sheet |
| No | No | Assem | Vessel | Sht No | No | No | 2&3) | 2&3) | 2&3) | |||||||
| 1 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | Existing Trays: See New Tray Data Sheet #8 | 1-26 | 21 | 21 | 21 | |
| 2 | 2 | 2 | Cone | CS | Distributor Traps | Note 1 | Note 1 | Below | 21 | 21 | 21 | |||||
| 26 | ||||||||||||||||
| 3 | 12 | 12 | 2440 | CS | Inflection Point Engineering MD Trays | 8 | 8 | Feed Point above Tray # 27 | Feed Point above Tray # 27 | Feed Point above Tray # 27 | Feed Point above Tray # 27 | 27-39 | 18, 21, 22 | 18, 21, 22 | 18, 21, 22 | |
| 4 | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Existing Collector And Blind Tray: No Modifications Required | Below | 21 | 21 | 21 | |
| 39 | ||||||||||||||||
Stabilizer, Item No V-2510 (Formerly Item No P-V2510)
Original Inflection Point Engineering Project Specification 6950-307 (1988)
REFERENCE:
Customer or Vendor Dwg. No. & Revision:
KOCH Dwg. No.: 31524-B-85-1
31524-E-85
31524-E-86
Note(s):
- Distributor Traps to suit new tray below.
Tray sections shall pass through existing 24” ND vessel manway.
| Service: Stabilizer | Service: Stabilizer | Service: Stabilizer | Item Number: V-2510 | Item Number: V-2510 |
|---|---|---|---|---|
| Tray Data | Tray Data | |||
| Tray Identification (Tray Numbers) | TOP (1-26) | BOTTOM (27-39) | ||
| Vessel ID, mm | 1830 | 2440 | ||
| Operating Pressure, kg/cm2(g) | 12.1 | 12.3 | ||
| Operating Temperature, C | 137 | 230 | ||
| Structural Design Temperature, C | 248 | 248 | ||
| Fluid Description | HCBN | HCBN | ||
| Foam Derating Factor | 1.00 | 1.00 | ||
| Vapor -Flow Rate, kg/h | 52188 | 168934 | ||
| Density, kg/m3 | 32.87 | 41.95 | ||
| Liquid -Flow Rate, kg/h | 51320 | 384351 | ||
| Density, kg/m3 | 459.39 | 524.61 | ||
| Viscosity, cP | 0.12 | 0.13 | ||
| Surface Tension, dynes/cm | 5.5 | 4.2 | ||
| Type of Tray | Valve | Inflection Point Engineering MD | ||
| For Sieve Trays | ||||
| Weir Height, M, mm | ||||
| Downcomer Clearance, N, mm | ||||
| Total Number of Holes | ||||
| Hole Diameter, mm | ||||
| Hole Area/Bubbling Area x 100 | ||||
| Tray spacing, S, mm (for exceptions see Project Specification 301 Vessels) | 600 | 450 | ||
| Notes | ||||
| Tray Layout | Use existing | |||
| Number of Passes | ||||
| A, mm (minimum) | ||||
| B, mm | ||||
| C, mm (minimum for 1 pass) | ||||
| D, mm | ||||
| E, mm | ||||
| F, mm | ||||
| G, mm (minimum) |
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