DGS MD 006 R1 Vessel Trays General

7/30/2019 DGS MD 006 R1 Vessel Trays General

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Abu Dhabi Oil Refining Company

VESSEL TRAYS - GENERAL DGS-MD-006Rev-1 April 2009

Takreer DGS-MD-006-Rev-1 April-2009 Printed 16-Apr-09 14:00:24 Initials Page 1 of 19

VESSEL TRAYS - GENERAL

Amendment Hi st ory

No Date Amendment Description Proposed Approved Incorporated

DGS Histo ry

1 April 2009 DGS-MD-006-Rev-1 Base Reference Project5578

TH/DDC QAM / MAY

0 March 2006 DGS-MD-006-Rev-0 Previous Project / LessonsLearnt Incorporated

TH/DDC ETSDM / EPDM

No Date Description Source Reviewed Approved

DGS-MD-006 Rev-1


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TABLE OF CONTENTS

1.0 GENERAL ................................................................................................................................3 1.1 INTRODUCTION.............................................................................................................3 1.2 PURP OSE.......................................................................................................................3 1.3 DEFINITIONS .................................................................................................................3

2.0 CODES AND STANDARDS .....................................................................................................3 3.0 REFERENCE DOCUMENTS ...................................................................................................4

3.1 PROJ ECT SP ECIFICATIONS.........................................................................................4 3.2 PROJ ECT STANDARD DRAWINGS .............................................................................4

4.0 DOCUMENT PRECEDENCE ...................................................................................................5 5.0 SPECIFICATION DEVIATION/CONCESSION CONTROL ......................................................5 6.0 QUALITY ASSURANCE/QUALITY CONTROL ........................................................................5 7.0 DOCUMENTATION ..................................................................................................................5 8.0 SUBCONTRACTORS/SUBVENDORS ....................................................................................6 9.0 HANDLING ...............................................................................................................................7

9.1 PACKAGING AND SHIPPING.........................................................................................7 10.0 VENDOR RESPONSIBILITIES ................................................................................................7

10.1 SYSTEM DESCRIPTION/PERFORMANCE REQUIREMENTS .....................................710.2 SUBMITTALS ..................................................................................................................810.3 TOLERANCES ................................................................................................................8 10.4 SUPPLIED BY TRAY/VESSEL VENDORS .....................................................................9

11.0 PRODUCTS ...........................................................................................................................10

11.1 DESIGN REQUIREMENTS...........................................................................................10 11.2 INSP ECTION AND TESTS ...........................................................................................16 11.3 IDENTIFICATION AND TAGGING ................................................................................16 11.4 PREPARATION FOR SHIP MENT .................................................................................17

12.0 INSTALLATION ......................................................................................................................17 ATTACHMENT 1 - TRAY PARTS TABLES ......................................................................................18 ADDENDUM SHEET .......................................................................................................................19

List of Authorized Signatures/ Initials

DGS Discipline Committee Member, ADRD ------------------------------

DGS Discipline Committee Member, RRD ------------------------------

DGS Discipline Committee Member Leader, E&PD Taha Hussein (TH)

Engineering & Technical Services Manager, E&PD Quazi Abdul Matin (QAM)


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Engineering & Projects Division Manager, E&PD Mohamed Al Yabhouni (MAY)

1.0 GENERAL

1.1 INTRODUCTION

1.1.1 Scope of Specification

This specification describes the minimum requirements for the design, materials selection,fabrication, assembly, inspection, and shipment of vessel trays.

1.1.2 Specific requirements for any particular trays will be furnished on the PROJ ECT trayprocess design data sheets and vessel data sheets/drawings.

1.2 PURPOSE

This specification is intended for use in the design and fabrication of vessel trays for theProject.

1.3 DEFINITIONS

For the purposes of this specification, the following definitions shall apply:

CONCESSION REQUEST - A deviation requested by the SUBCONTRACTOR orVENDOR, usually after receiving the contract package or purchase order. Often, it refersto an authorization to use, repair, recondition, reclaim, or release materials, components or

equipment already in progress or completely manufactured but which does not meet orcomply with COMPANY requirements. A CONCESSION REQUEST is subject toCOMPANY approval.

SHALL - Indicates a mandatory requirement.

SHOULD Denotes an action or requirement which is not mandatory but which is stronglyrecommended.

2.0 CODES AND STANDARDS

It shall be the VENDOR'S responsibility to be, or to become, knowledgeable of therequirements of the referenced Codes and Standards.

The following Codes and Standards shall, to the extent specified herein, form a part of thisspecification. The latest edition in force shall apply.

ASME Boi ler and Pressure Vessel Code:

Section II Parts A, B & C Material Specifications

Section II Part D Material Properties


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Section VIII Division 1 Pressure Vessels

Section VIII Division 2 Pressure Vessels-Alternative Rules

American Iron and Steel Inst it ute:

As Specified

American Soc iety for Test ing and Materials :

B127 Specification for Nickel-Copper Alloy (UNS N04400) Plate, Sheet,and Strip

B164 Specification for Nickel-Copper Alloy Road, Bar, and Wire

International Organization for Standardization (ISO):

ISO 9001 - 2000 Quality Management System Requirements

ISO 9004 - 2000 Quality Management Guidelines for Performance ImprovementSystem

ISO 9011 Guidelines for Quality and/or Environmental System Auditing

3.0 REFERENCE DOCUMENTS

The following reference documents, to the extent specified herein, form a part of thisspecification.

3.1 PROJECT SPECIFICATIONS

DGS-MD-002 Pressure Vessels - General

DGS-MD-004 Pressure, Vessels - Supplement for Austenitic Ferritic and DuplexHigh Alloy Steel, Nickel and Nickel Alloys

DGS-MD-005 Pressure Vessels - Supplement for Alloy Lined Steel

DGS-MU-002 Preservation and Export Packing

DGS-MU-013 Criticality Rating System

DGS-MU-014 Minimum Shop Inspection and Certification Requirement

3.2 PROJECT STANDARD DRAWINGS

STD-MD-00034 Tray Support Tolerances

STD-MD-00035 Tray Tolerances


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STD-MD-00052 Tray Support Rings

4.0 DOCUMENT PRECEDENCE

The VENDOR shall notify the CONTRACTOR of any apparent conflict between thisspecification, the related data sheets, the Codes and Standards and any otherspecifications noted herein. Resolution and/or interpretation precedence shall be obtainedfrom the CONTRACTOR in writing before proceeding with the design/manufacture.

In case of conflict, the order of precedence shall be stated in the AGREEMENT or otherPROJ ECT documents as applicable.

5.0 SPECIFICATION DEVIATION/CONCESSION CONTROL

Any technical deviations to this specification and its attachments including, but not limitedto, the Data Sheets and Narrative Specifications shall be sought by the VENDOR onlythrough CONCESSION REQUEST format. CONCESSION REQUESTS requireCONTRACTOR'S and COMPANY'S review/approval prior to the proposed technicalchanges being implemented. Technical changes implemented prior to COMPANYapproval are subject to rejection.

6.0 QUALITY ASSURANCE/QUALITY CONTROL

Quality Management Systems shall comply with the applicable requirements of ISO 9001 2000. The CONTRACTOR shall ensure that the VENDOR shall have in effect at alltimes, a QA programme, which clearly establishes the authority and responsibilities of

those responsible for the quality system. Persons performing quality functions shall havesufficient and well-defined authority to enforce quality requirements that they initiate oridentify and to recommend and provide solutions for quality problems and thereafterverify the effectiveness of the corrective action.

Quality System and Quality Control requirements shall be identified and included in theCONTRACTORs Purchase Documentation. Based on these requirements the VENDORwill develop a QA/QC programme which shall be submitted to the CONTRACTOR forreview and concurrence. The VENDORs QA/QC programme shall extend to SUB-CONTRACTORS and SUB-SUPPLIERS.

COMPANY/CONTRACTOR reserves the right to inspect materials and workmanship at allstages of manufacture and to witness any or all tests. The VENDOR, 30 days after award

but prior to the pre-inspection meeting, shall provide the CONTRACTOR with a copy of itsManufacturing and Inspection Plan for review and inclusion of any mandatoryCOMPANY/CONTRACTOR witness or hold points.

7.0 DOCUMENTATION

VENDOR shall submit the type and quantity of drawings and documentation forCONTRACTORS authorization or information as listed in the individual MaterialRequisitions and Purchase Orders.


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Mutual agreement on scheduled submittal of drawings and engineering data shall be anintegral part of any formal Purchase Order.

Comments made by CONTRACTOR on drawing submittal shall not relieve VENDOR orSUBVENDORS of any responsibility in meeting the requirements of the specifications.Such comments shall not be construed as permission to deviate from requirements of thePurchase Order unless specific and mutual agreement is reached and confirmed inwriting.

Each drawing shall be provided with a title block in the bottom right-hand cornerincorporating the following information:

Official trade name of the COMPANY.

VENDORS drawing number.

Drawing title giving the description of contents whereby the drawing can beidentified.

A symbol or letter indicating the latest issue or revision.

PO number and tag numbers of the equipment in which the trays are to be installed.

Revisions to drawing shall be identified with symbols adjacent to the alterations, a brief description in tabular form of each revision shall be given, and if applicable, the authorityand date of the revision shall be listed. The term "Latest Revision" shall not be used.

8.0 SUBCONTRACTORS/SUBVENDORS

The VENDOR shall assume unit responsibility and overall guarantee for the vessel traypackage and associated material.

The VENDOR shall transmit all relevant purchase order documents includingspecifications to his SUBVENDORS and SUBCONTRACTORS.

It is the VENDOR'S responsibility to enforce all Purchase Order and Specificationrequirements on his SUBVENDORS and SUBCONTRACTORS.

The VENDOR shall submit all relevant SUBVENDOR and SUBCONTRACTOR drawings

and engineering data to the CONTRACTOR. The VENDOR shall obtain and transmit all SUBVENDOR and SUBCONTRACTORwarranties to the CONTRACTOR/COMPANY, in addition to the system warranty.


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9.0 HANDLING

9.1 PACKAGING AND SHIPPING

Preparation for shipment shall be in accordance with the VENDOR'S standards and asnoted herein. VENDOR shall be solely responsible for the adequacy of the preparation forshipment provisions with respect to materials and application, and to provide equipment atthe destination in ex-works condition when handled by commercial carriers.

Adequate protection shall be provided to prevent mechanical damage and atmosphericcorrosion in transit and at the jobsite.

Preparation for shipment and packing will be subject to inspection and rejection byCOMPANY'S/CONTRACTOR'S inspectors. All costs occasioned by such rejection shall beto the account of the VENDOR.

After inspection and test, trays shall be completely free of water and dry before start of preparation for shipment.

Trays shall be packed to prevent damage during transit, lifting, or unloading.

Separate, loose, and spare parts shall be completely boxed. Pieces of loose or spare partsshall be identified by item number and service and marked with CONTRACTORS ordernumber, tag number, and weight, both inside and outside of each individual package orcontainer. A bill of material shall be enclosed in each package or container of parts.

One complete set of the installation, operation, and maintenance instructions shall bepacked in the boxes or crates with equipment. This is in addition to the number called forin the Purchase Order.

All trays and material shall be preserved and export packed in accordance with ProjectPreservation and Export Packing Specification, DGS-MU-002.

10.0 VENDOR RESPONSIBILITIES

10.1 SYSTEM DESCRIPTION/PERFORMANCE REQUIREMENTS

10.1.1 The tray VENDOR shall guarantee that the equipment provided shall meet the operatingconditions specified. In case the equipment does not fulfill the performance guarantee,the tray VENDOR shall, without cost to CONTRACTOR/COMPANY, furnish such newequipment or redesign and rebuild the equipment furnished in order to meet theperformance guarantee, where trays are specified as being installed by VESSELVENDOR at his works or by SUBCONTRACTOR in field, then TRAY VENDOR shallprovide a suitable Supervisor to supervise their installation.

10.1.2 Leakage rates, when specified, shall be certified by the tray VENDOR.


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10.2 SUBMITTALS

10.2.1 General

a. VENDOR shall submit engineering data for review. All documents shall be inreproducible form and the quality shall allow for microfilming without loss of clarity.Each document shall indicate that it has been checked before submittal.Fabrication shall not proceed until notification has been received fromCONTRACTOR.

b. Review of VENDOR'S documents by CONTRACTOR does not relieve VENDOR of the responsibility for compliance to the applicable codes, standards,CONTRACTOR data sheets/drawings and specifications, or the accuracy of shopdimensions.

c. VENDORS drawings, calculations, and engineering data shall be in Englishlanguage.

d. Units of measurement shall be per project specification DGS-MD-002.

10.2.2 Tray Vendor

The tray VENDOR shall provide the following:

a. Tray performance calculations.

b. All drawings required for the fabrication and assembly of the trays.

c. Detail drawings of tray support rings, downcomer bars, beam supports, and all othertray support parts, including required weld sizes. Tray attachment drawings shallbe supplied in sufficient time to enable the vessel VENDOR to adhere to deliveryschedule.

d. Complete installation instructions and parts list (for record purposes only).

e. List of all components and their ASME or ASTM materials specification and grade.

10.2.3 Vessel Vendor

The vessel VENDOR shall provide tray support detail drawings based on tray VENDORattachment drawings or basic data.

10.3 TOLERANCES

10.3.1 Tray Supports

Dimensional tolerances shall apply to the completed vessel and shall conform to standarddrawing STD-MD-00034.


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10.3.2 Tray Assembly

Dimensional tolerances shall apply to the assembled trays and shall conform to standarddrawing STD-MD-00035.

10.4 SUPPLIED BY TRAY/VESSEL VENDORS

10.4.1 Tray Vendor

a. Tray designs shall be based on the process and mechanical design conditionsspecified on Project tray process design data sheets, vessel drawings, and thisspecification. Tray diameters and number of passes specified are a preliminaryselection and alternatives shall be proposed if required to meet the performanceguarantee.

b. Tray assembles shall include all component parts such as, but not limited to, traydecks, weirs, downcomers, insulating baffles, drawoffs, troughs, seal pans, valves,risers, bubble caps, beams, trusses, clamps , bolts, nuts, washers, gaskets, andpacking.

c. Both tray assembly hardware and the greater of the following quantities shall besupplied;

Bolts and Nuts: 10 percent excess or 10 of each type.

Washers (metal or non-asbestos): 10 percent excess or 10 of each type.

Tray Clamps: 10 percent excess or 5 pieces.

Gaskets and Packing: 25 percent excess or 10 feet.

d. The Tray VENDOR shall supply design for tray support bars, downcomer bars,beam supports, and all other tray support parts welded to the vessel. For traysinstalled in vessel at VESSEL VENDORs works and transported in horizontalposition, TRAY VENDOR shall consider forces imposed during transport and liftingin his tray design.

10.4.2 Vessel Vendor

a. The vessel VENDOR shall provide tray support bars, downcomer bars, beamsupports, and all other tray support parts welded to the vessel, in accordance withthe tray VENDORS drawings and this specification.

b. When specified in the Purchase Order, tray assemblies in accordance with the trayVENDORS drawings and instructions and with this specification.


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11.0 PRODUCTS

11.1 DESIGN REQUIREMENTS

11.1.1 Design Criteria

a. General

VENDOR shall allow for manufacturing tolerances on both the vessel andtrays. Specific allowance shall be made for vessel shell out-of-roundnesspermitted by the applicable vessel code. Allowance shall be made fordifferential thermal expansion between the vessel shell and the trays duringnormal startup, operation, and normal and emergency shutdown.

Tray parts (except parts welded to the vessel) affected by tolerance dimensionsspecified in standard drawings STD-MD-00034 and STD-MD-00035, shall bemade adjustable, so that when installed, the trays and pans shall be within thespecified tolerances.

Like parts of tray assemblies shall be made interchangeable. Symmetrical traylayouts shall be used wherever possible.

Tray parts shall be removable through the vessel manways. Exceptions to thisrequirement are large major beams and trusses.

The weight of any single piece of removable tray and manway panel shall not

exceed the following criteria: 35 kgs when vessel diameter is 1.2 meter or less.

70 kgs when vessel diameter is over 1.2 meter.

Tray and downcomer sections shall be securely clamped or other quickfastening system to the support rings, bars, and truss members. Bolted jointsshould be avoided except for attachment of support beams to support clips, forattachment of downcomer plates and for the attachment of auxiliary internals.When the connections of beams to support clips are essential to the integrity of the tray construction, bolted connections shall be secured by means of tackwelding the nut to the bolt, or by employing a second nut. Where required,

these shall be sealed with suitable gaskets. Trays shall have internal tray manways to provide access to all parts of the

trays. Tray manways shall be aligned vertically whenever feasible, and shallbe removable from both top and bottom. Small tray sections may be used formanways. Tray manways shall have a minimum opening of 320 x 500 mm.Where this is impossible for construction reasons, the use of smaller manholesshall be subject to the approval of the CONTRACTOR/COMPANY. Themanway shall never be smaller than 270 x 450 mm. If the clearance betweenthe tray deck and the bottom of major supporting beams of the tray above is


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less than 400 mm, tray manways shall be provided on each side of the beams.VENDOR shall ensure that passage of a man is possible through traymanholes in the installed position.

Tray spacing shall be as specified on Project vessel data sheets/drawings. Fortransition trays, redistribution areas, chimney trays, location of demisters, the

TRAY VENDOR may adjust the tray spacing with CONTRACTORs agreement.

Major support beams shall be parallel to the flow of liquid. Total height of support beams shall not exceed one half of the tray spacing.

For minor support beams on conventional downcomer trays where beams areperpendicular to the direction of liquid flow, the beam shall occupy not more

than one third of the space between the trays, as defined by:Abeam /(D x TS)


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installation and removal through the column top. Columns with diameter 800mm or larger shall have tray support rings welded to the vessel shell perstandard drawing STD-MD-00052.

Cartridge and pedestal type trays shall be designed to minimize edge leakage.

Unless otherwise specified, all trays shall be designed to permit installation andremoval from the top side of the tray.

Except for total draw-off trays, at least one 13 mm diameter drain hole shall beprovided on each tray or pan to permit draining of the liquid hold-up. Drainholes in recessed seal pans shall be located downstream or on the tray side of the downcomer so that any vapor passing through the holes will not by-pass

the tray above. Inlet weirs shall have a 13 mm hole at the base to drain intothe tray. No drain holes shall be provided in total draw-off trays.

Allowance shall be made for differential pressure between the trays upper andlower sides during normal start-up, operation, and normal and emergencyshutdown.

For high flow rate service, tray VENDOR shall check and recommend whether jumper baffles are required at the center and/or off-center downcomers of multipass trays. These requirements apply to all types of trays.

b. Minimum Thickness and Corrosion Allowance

Minimum thickness of tray parts including corrosion allowance shall be listed inAttachment 1, Table 1.

The size and minimum thickness of tray support rings, downcomer supportbars, and beam clips including corrosion allowance shall be determined by thetray VENDOR.

Minimum corrosion allowance for tray parts shall be as follows:

Monel or stainless steel trayparts

None

Carbon steel tray parts 0.76 mm total

Minimum corrosion allowance for tray support rings, downcomer support bars,and beam clips shall be as follows:

Monel or stainless steel 1.6 mm total

Carbon and low alloy steel 3.0 mm total

c. Loads and Deflections


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Design Loads All trays, pans, and supports shall be designed for the corroded thickness

at operating temperature.

Trays and pans shall be designed for a uniform live load of the greater of 200 kg/m 2 or the weight of liquid at 50 mm over the maximum weir settingwith dead load.

Areas below downcomers shall be designed for a uniform live load of 300kg/m 2 or a liquid load of 450 mm with dead load, whichever is greater.

Shed rows and disc-and-donut types of trays with no normal operating

liquid level shall be designed for a uniform live load of 120 kg/m 2 on theprojected horizontal area with dead load.

Support beams and connections shall be designed for the total dead andlive loads of the supported parts.

For maintenance purposes, trays and pans, together with their supportmembers, shall be designed for a concentrated live load of 110 kg at anylocation on the installed assembly independent of other designed liveloads and based on a design temperature of 38C

Deflections

The calculated combined deflection of tray and support beam due tooperating loads shall not exceed the smaller of 1/800 times vessel ID(in mm), or 5 mm.

Support beams or trusses may be cambered subject to CONTRACTOR'Sapproval.

Levelness

The maximum tilt of trays shall be 0.3% of the column diameter or 6 mm,whichever is less.

Local depressions and bulges in tray panels shall not exceed 6 mm fromnominal level.

d. To facilitate installation and maintenance, trays and other internals shall be made insections which shall pass through manholes or top dome of the column. Forpassage of sumps and troughs of draw-off trays, a top dome should be provided if possible. For other tray parts, 610 mm nominal manholes shall be provided.Manhole size for small diameter columns shall be analyzed on a case by case basisand shall never be smaller than 460 mm internal diameter. The following location of column manholes is recommended:


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Every 10 fractionating or contacting trays Next to gas or liquid inlet devices

Below draw-off trays

In the bottom compartment

Top of the column

11.1.2 Basic Materials and Methods

a. Tray Supports

Materials for tray support rings and other tray parts welded to the vessel shallbe as specified on project vessel data sheets/drawings.

Where support beams or other materials are bolted to the vessel wall, slottedholes shall be provided. The location of these slots shall be determined by thetray VENDOR.

b. Trays, Valves, and Hardware

Materials for tray assemblies shall be as specified on project's process design datasheets, vessel drawings, and as noted in Attachment 1, Table 2.

c. Internal DistributorsInternal distribution pipes shall have flanged connections.

d. Gaskets

Where used, gaskets and sealing washers shall be 3 mm thick.

Gaskets shall be woven tape and packing shall be braided rope fabricatedfrom asbestos free materials suitable for the process fluid and temperature.Proposed materials are subject to CONTRACTOR'S approval.

e. Bolting

Alloy steel bolts for tray assemblies shall not be smaller than 10 mm diameter andcarbon steel bolts shall not be smaller than 12 mm diameter. Bolt length shall bechosen such that after installation of the nut(s), only 2-3 threads remain exposed.

f. Substitution

Substitution of materials must have CONTRACTOR'S written approval beforefabrication.


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11.1.3 Fabrication and Manufacture

a. Welding

Tray support rings shall be welded to the vessel with continuous welds both topand bottom. The top weld shall be designed as a strength weld, and the weldon the underside shall be a seal weld.

Downcomer support bars may be continuously welded to the shell from oneside only if the other side is not accessible.

Carbon steel vessels with applied alloy strip linings shall have the liningstripped back to allow the alloy support parts to be welded to the carbon steel

shell. The lining shall be attached to the support parts in a manner that shallensure adequate corrosion protection. Details must be submitted forCONTRACTOR'S review.

In vessels constructed from integrally clad or overlayed material, support partsshall be attached directly to the alloy cladding or overlay. The area that theattachment will be welded to shall be inspected by ultrasonic test to ensureintegrity of the cladding bond before welding.

Welder's, welding operators, and welding and NDE procedures used forwelding parts to the vessels shall be subject to the same qualifying proceduresrequired in the fabrication of the vessel.

Procedures for welding tray parts shall be submitted to CONTRACTOR forreview.

b. Workmanship

Surfaces of fabricated parts shall be smooth and free from scale, dents, andother defects.

Perforations for sieve trays shall be punched downwards from the top sides of trays.

Punched valve tray perforations shall be burr side up. An exceptions is made,however, for the holes for snap-in valves which shall be burr side down, to

facilitate mounting of the valves.

Exposed edges of trays at locations where men may pass shall be beveled orrounded off, e.g. edges of manways, top edges of weirs.

Burrs shall be removed from perforated areas of trays.

If nuts are welded to tray parts, the threads shall be chased after welding.


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11.2 INSPECTION AND TESTS

11.2.1 General

Trays and pans shall be subject to inspection by CONTRACTOR in the shop where theyare fabricated. Such inspection shall not relieve VENDOR of any responsibility for theperformance guarantee.

11.2.2 Trial Assembly

One tray assembly from each group of similar trays shall be trial assembled in the trayVENDOR'S shop from parts selected at random to ensure that parts are properly detailedand that fitup is correct. The trial assembly shall be supported in a manner comparable tofinal installation. The VENDOR shall notify CONTRACTOR (5) five working days beforethe date on which the trial assembled tray shall be ready for inspection.

11.2.3 Leakage Test

a. The following trays or tray parts shall pass the leakage test:

Total draw-off trays over full height

Partial draw-off trays over full height

Bubble cap trays up to weir or riser height

Downcomersb. With all drain holes plugged and water level at the height indicated in paragraph

11.2.3.a, the drop in level shall not exceed 5 cm in 30 min. Leakage through joints of bubble cap trays shall be uniformly distributed across the tray.

c. After testing, all plugs shall be removed.

d. VENDOR shall certify that the trays concerned will not exceed the stated leakagerate based upon an actual leakage test stated above. This certification may bebased on tests of trays of identical design but not necessarily of the same size.

11.3 IDENTIFICATION AND TAGGING

11.3.1 Tray Parts

Each tray part shall be piece marked with identification designations as shown on the trayVENDOR'S assembly drawings; nonleaded paint or an approved dye shall be used formarking.


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11.3.2 Hardware

Small parts such as bolting, washers, and clips shall be packaged and marked withadequate identification.

11.4 PREPARATION FOR SHIPMENT

11.4.1 Equipment shall be packed to suit the particular mode of transportation in order to preventdamage during shipment. All packages shall be marked with CONTRACTOR'S POnumber, vessel equipment number, and tray numbers.

11.4.2. Each tray assembly shall be packaged as a complete unit.

11.4.3 If required, equipment shall be packaged for overseas shipment in accordance withspecial instructions given in the PO.

11.4.4 Tray parts for different vessels shall not be intermixed.

11.4.5 In addition to the requirements of Section 10.2.2., of this specification, a copy of parts listand installation instructions/drawings shall be included in the shipment for each vessel.

12.0 INSTALLATION

12.1 Tray assemblies shall be installed in accordance with the tray VENDOR'S drawings andinstructions.

12.2 Seal welding of tray parts, if required, shall be welded from the top side wheneverpossible. Tray VENDOR shall specified the total weld length and type of welding process.

12.3 In general, side sumps and troughs shall be of fully welded construction. Welding of draw-off tray parts to each other during site erection is not allowed unless it is strictly required inview of manhole dimensions constraints. Welding of draw-off tray parts to column supportsis not allowed.

12.4 Gasketed joints below normal liquid level shall be avoided wherever possible. Longstraight joints below normal liquid level, when they cannot be avoided, shall be seal orstrength welded. Facing or circular joints to pipe connections shall be machined (stock-finished).


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At tachment 1 - Tray Parts Tables

Table No. 1 Tray Parts Minimum Thickness (including corrosion allowance)

Parts CategoryCarbon Steel

(mm)12 Cr, 18 Cr - 8Ni,and Monel (mm)

Valves - 1.60Bubble Caps and Risers 3.40 1.60

Tray Floors, Downcomers 3.40 2.00

Beams and Trusses 3.00 3.00

Table No. 2 Tray Parts Specified Materials

Material Category(specified on

vessel drawing)

Trays, weirs,downcomers, trusses,

beams, caps, risers Valves

Bolts, clamps,fasteners(Note 1)

Carbon Steel

CommercialQualityCarbon Steel AISI 410

CommercialQualityCarbon Steel(Note 2)

12 Cr. Steel AISI 405,410S AISI 410 AISI 41018 Cr - 8Ni Steel AISI 304L,321,347,etc. AISI 304, 321, 347 AISI 304Monel ASTM B 127 ASTM B 164

Class A

NOTE: 1. Nuts shall be of similar material as the bolts, but carefully chosen to minimizegalling of the threads.

2. Carbon Steel trays shall have AISI 410 bolting for tray manways.


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ADDENDUM SHEET

All revisions to this DGS subsequent to the issue of Rev Zero shall be recorded in thisaddendum sheet and shall be incorporated into the DGS in the next revision.

Date Proposed Revision Remarks

Documents

DGS MD 006 R1 Vessel Trays General