TECHNICAL SPECIFICATION EXTERNALLY FINNED TUBES
DATE: 25 MAR MAR 2003
ENGINEERING SERVICES BY KBR TECHNICAL SERVICES, INC.
MB21-5F PAGE 1 OF 4
TABLE OF CONTENTS Section 1. 1.1 1.2 2. 2.1 2.2 3. 3.1 3.2 3.3 4. 4.1 4.2 4.3 4.4 4.5
Title Page No. GENERAL ......................................................................................................................................1 Scope..............................................................................................................................................1 KBR Documents, Codes, and Industry Standards. .................. ........................... .................. ................... ................... .................. .................1 ........1 COMPONENTS AND MATERIALS ...............................................................................................2 Tubes ................................. ................ ................. ................. ................................. ................ ................. ................. .................... ................. .....2 Fin Material ................. ................. ................. ................................. ................ ................. ................. ..................... ...........2 ........... 2 FABRICATION ...............................................................................................................................2 General ................................. ................ ................. ................. ................................. ................ ................. ................. .................... ...................2 ................ ...2 Manufacture....................................................................................................................................2 Welding ................................ ............... ................. ................. ................. ................. ................. .................... ...................3 ................ ...3 TESTING AND INSPECTION ........................................................................................................3 General ................................. ................ ................. ................. ................................. ................ ................. ................. .................... ...................3 ................ ...3 Tube Material ................................. ................ ................. ................................. ................ ................. ................. ................. ................... ...........3 ........... 3 Fin Material ................. ................. ................. ................................. ................ ................. ................. ..................... ...........3 ........... 3 Finned Tubes ................. ................. ................. ................. ................. ................. .................... ........3 Samples ................................ ............... ................. ................. ................. ................................. ................ ................. .................... ................. ..4
1. GENERAL 1.1 Scope 1.1.1 This Specification, KBR KBR Purchasing Standards MB2-1PS and SDR-2MB-2, cover the requirements for shop fabrication, testing, and inspection of externally finned tubes, where the fin material is either solid or segmented. Exceptions to this specification, specification, if any, and abbreviations are in accordance with with KBR Technical Standard MB15-1TS (Note: KBR will be referred to as the Purchaser). 1.1.2 The Purchaser will specify specify materials, shape, and dimensions of fins fins required to be furnished by the Supplier. 1.1.3 This specification covers tolerances tolerances and tests, as required to control the quality quality of the finished finned tube and assure compliance with the Purchaser's requirements. 1.2 KBR Documents, Documents, Codes, and Industry Industry Standards Standards The following documents are referenced referenced herein and form part of the Order. Additional KBR documents, documents, when applicable, will be listed listed in the Requisition. Applicable dates of issue of industry standards and codes shall be as indicated in the KBR Technical Standard MB15-1TS. KBR DOCUMENTS MB2-1PS, "Purchasing Requirements for Furnace Materials, Components and Equipment" MB15-1TS, "General Furnace Specification" SDR-2MB-2, "Supplier Data Requirements-Fabricated Requirements-Fabricated Furnace Components" AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) ASME Boiler and Pressure Vessel Code: Section I, Section VIII, ASME B31.3,
"Power Boilers" "Pressure Vessels" Division 1 "Process Piping"
TECHNICAL SPECIFICATION EXTERNALLY FINNED TUBES
DATE: 25 MAR 2003
ENGINEERING SERVICES BY KBR TECHNICAL SERVICES, INC.
MB21-5F PAGE 2 OF 4
AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM A167, "Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet, and Strip" ASTM A176, "Stainless and Heat-Resisting Chromium Steel Plate, Sheet, and Strip" ASTM A1008, "Steel, Sheet, Cold-Rolled, Carbon, Structural, High-Strength Low-Alloy and High-Strength Low-Alloy with Improved Formability" 2. COMPONENTS AND MATERIALS 2.1 Tubes Unless otherwise noted on the Purchase Order, all materials designated by mark numbers on design drawings and listed in the Bill of Material, will be supplied by the Purchaser and shipped to the finning fabricator. The balance of materials needed to complete finned tube assembly shall be supplied by the finning fabricator unless noted (N.F.). Material supplied shall conform to the Specifications stated on the design drawings. (Note: "N.F." denotes Not Furnished by the fabricator.) 2.2 Fin Material 2.2.1 Nominal fin material thickness shall be specified by the Purchaser. The minimum thickness shall be as specified, ± 0.005 inch (0.127 mm) mill tolerance. 2.2.2 The fins will be manufactured from carbon steel (ASTM A1008, Type B), 11-13Cr (ASTM A176, TP 410), 18Cr-8Ni (ASTM A167, TP 302B), or 25Cr-20Ni (ASTM A167, TP 310) stainless steel in accordance with the Purchaser's requirements. TP 409 material may be used for 11-13Cr fins provided mill test reports confirm the chemical composition meets the Purchaser required minimum chromium content of 11%. ASTM A240 is acceptable alternate to ASTM A167 and ASTM A176. 2.2.3 Mill test reports shall be supplied for fin material. 3. FABRICATION 3.1 General 3.1.1 The finner shall submit an established finning procedure for Purchaser acceptance. No deviation from the accepted procedure is allowed without Purchaser concurrence. 3.1.2 Fabrication of tubes shall meet the requirements of the applicable Purchaser specifications noted in the Inquiry. 3.2 Manufacture 3.2.1 Prior to the application of fins, the exterior of the tubes shall be properly cleaned to remove scale, rust, oil, grease and other deleterious foreign materials. 3.2.2 The fin shall be solid or segmented, as specified, and wound helically around the tube in such a manner o o as to leave the major height of the fin in a position 90 (±10 ) to the tube. 3.2.3 For segmented fins, the maximum distance between the outside diameter of the tube and the base of the segmented portion of the fin shall not exceed 0.25 inch (6.4 mm). 3.2.4 The fin is considered to be a nonpressure part attachment having no load carrying function joined to a pressure part by a machine welding process. The fin-to-tube weld is not to be considered a strength or pressure containing weld.
TECHNICAL SPECIFICATION EXTERNALLY FINNED TUBES
DATE: 25 MAR 2003
ENGINEERING SERVICES BY KBR TECHNICAL SERVICES, INC.
MB21-5F PAGE 3 OF 4
3.3 Welding 3.3.1 Fins shall be attached by the high frequency resistance welding method. The following additional requirements shall apply: a.
Moderate interruptions of the weld are permissible providing the sum total length of such interruptions does not exceed 2.0% of the total length of the weld on any tube. The maximum permissible length of an interrupted weld at a break in the fin strip shall be a function of the pipe diameter: for a NPS 2 pipe, the maximum interrupted weld length shall be 5 wraps of the tube; for a NPS 3 or NPS 4 pipe the maximum interrupted weld length shall be 4 wraps of the tube; and for a NPS 5 or NPS 6 pipe the maximum interrupted weld length shall be 3 wraps of the tube. The distance between two interruptions shall not be less than 6 inches (150 mm). Other than at a break in the fin strip, the maximum interrupted weld length shall not exceed two (2) linear inches (50 mm).
b.
The fin height after welding shall be as specified ±1/32 inch (0.8 mm) as measured from the base tube to the fin tip.
c.
Warping of tubes due to finning shall not exceed 3/16 inch (4.8 mm) in any 10 feet (3.0 m) section of tube.
d.
Length of nonfinned portions on the finished finned tube shall be as specified ±1/4 inch (6.4 mm).
3.3.2 Weld reinforcement shall be ground smooth and level with the adjacent tube or pipe prior to attachment of fins. 4. TESTING AND INSPECTION 4.1 General The inspector representing the Purchaser shall have entry at all times, while work on the contract of the Purchaser is being performed, to all parts of the manufacturer's works that concern the manufacture of the material ordered. The manufacturer shall afford the inspector all reasonable facilities to ensure that the material is being furnished in accordance with this specification. All required tests and inspection shall be made at the place of manufacture prior to shipment unless otherwise specified and will be conducted so as not to interfere unnecessarily with the operation of the works. 4.2 Tube Material Upon arrival at the finner, tubes shall be visually inspected to verify dimensions and correct material identification. Tube will also be inspected for obvious defects including dents, laminations, gouges, out-of-roundness and surface finish. Any condition considered deleterious to the end use of welding of the fins to the tube shall be reported to the Purchaser for disposition. 4.3 Fin Material 4.3.1 Fin material shall be inspected upon receipt to verify dimensions and proper material identification. Fin material shall also be inspected for corrosion and lamination. 4.3.2 During finning, fin material shall be inspected to verify proper material identification, dimensions and integrity prior to being welded to the tube. 4.4 Finned Tubes 4.4.1 During finning, the welding operator may stop the machine and physically remove a short portion of the fin to verify the presence of an adequate weld.
TECHNICAL SPECIFICATION EXTERNALLY FINNED TUBES
DATE: 25 MAR 2003
ENGINEERING SERVICES BY KBR TECHNICAL SERVICES, INC.
MB21-5F PAGE 4 OF 4
4.4.2 To verify the extent and quality of the fin to tube bond, a small portion of fin shall be removed from the end of every 5th tube and the surface visually inspected. The average width of the white metal exposed by removing the fin shall be a minimum of 90% of the original thickness of the fin, and generally continuous over the whole length exposed. 4.4.3 The maximum amount of corrugation of a solid fin at the attachment to the tube shall be 3 times the original thickness of the fin, measured from out to out of the corrugations in the plane of the fin. 4.4.4 The inside surface of all finished finned tubes shall be visually inspected. The outside shall be free from injurious defects and have a workmanlike finish. 4.5 Samples 4.5.1 A minimum of two (2) welded fin tube samples shall be submitted with the quotation. The samples will be used for bid evaluation and will be retained by Purchaser for future inspection/rejection comparison purposes. 4.5.2 The size of each sample shall measure 6 inch (150 mm) long by 120 degrees. One sample shall represent the minimum acceptable standard and the other shall represent the normal standard. 4.5.3 The actual number of sample pairs submitted with the quotation will suit the range of materials in the Inquiry and ensure the provision of future inspection tools for the materials in the Purchase Order. Any problems in providing the sample pairs; or of the selection of sample equivalent materials; shall be discussed with Purchaser, prior to the submission of the quotation. 4.5.4 Subject to the approval of the Purchaser, additional samples may not be required if Supplier has submitted samples with a previous quotation.
