Memo 2010-12-01 (rev. 2) To Copy From Trælnes, Hege Subject TR2000 Piping and Valve Materials under PED. The usage of this standard based on ASME B31.3 1 Introduction and objective Reference is made to PMA (Particular Material Appraisal) of TR2000 RO-RAM in 2007. This document is an updated version of PED TK 2DV TR2000. Changes in chapter 2 and 3 are revision marked. (Spelling errors and updates according to format changes are not marked). The piping and valve material standard TR2000 is the governing specification for piping and valves in Statoil. The objective of the document here in is to get acceptance of using ASME B31.3 and the material specified in TR2000 under PED (The Pressure Equipment Directive in Europe). A TR2000 EC master material component is a set of dummy piping classes that lists the specific materials. It has one piping class for each material. It does not contain wall thickness, and pressure rating given is only typical. When a complete piping class is made for a project, the material is retrieved from the dummy piping class and wall thickness and pressure rating are added to it. This document must thus be regarded as an integral part of TR2000 EC master material component. The materials as listed in section 3 below are considered. The objective of section 3 below is to clarify usage of ASME B31.3 for specific items that might else be subject to discussion, i.e. clarify that the items as brought forward are acceptable under PED 97/23 EC. As regards material data sheets, the new system s character setting is described in TR2000 Piping and valve specification; EC master material components, Section 1 General. Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 1 of 14
2 Material, allowable stress, temperature and pressure rating For pressure rating see also Appendix A Pressure rating 2.1 22 Cr S31803 duplex material (DX) Materials As listed in TR2000 EC master material component piping class DX including MDS and SST: Pipes: A790, A928 1) Pipe fittings: A815 2) Forging: A182 F51 Plates: A240 1) When TR2000 uses 0.3 mm under tolerance in wall thickness calculations, ASME B36.10-U03 is called off in the specification. The associated MDS clarifies that the material shall be supplied with not more than 0.3 mm wall thickness under tolerance and shall be marked accordingly. 2) As for note (1), but for fittings, ASME B16.9-U03 Allowable stress According to A790 as listed in Table A-1 of ASME B31.3 for all materials. Maximum operation temperature: Minimum design temperature: 300 C. In saliferous atmosphere, based on evaluation, the material is limited to 110 C when exposed to such environment over time to reduce risk for stress corrosion cracking. -46 C Flange standard ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Rating according to Group 1.2 material in ASME B16.5 See note (a) and note (b) below and Appendix A Note (a): Material is stronger than the lowest strength material listed in group 1.2. For flange rating ASME B16.5 metric version of 1981 is the basis. This rating has been used by Statoil since 1992 with good experience. Note (b): The welding end length of the neck is shorter than in the ASME B16.5 standard (see flange MDS es in TR2000 EC Master Material Components). This increase the pressure capacity of the flange compare to a standard flange. 2.2 25 Cr duplex, S32760 As listed in TR2000 EC master material component piping class DX including MDS and SST: Pipes: A790, A928 1) Pipe fittings: A815 2) Forging: A182 F55 Plates: A240 Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 2 of 14
1) When TR2000 uses 0.3 mm under tolerance in wall thickness calculations, ASME B36.10-U03 is called off in the specification. The associated MDS clarifies that the material shall be supplied with not more than 0.3 mm wall thickness under tolerance and shall be marked accordingly. 2) As for note (1), but for fittings, ASME B16.9-U03 Allowable stress According to A790 as listed in Table A-1 of ASME B31.3 for all materials. Maximum operation temperature: Minimum design temperature: 300 C. In saliferous atmosphere, based on evaluation, the material is limited to 120 C when exposed to such environment over time to reduce risk for stress corrosion cracking. -46 C Flange standard ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Rating according to Group 1.2 material in ASME B16.5. This is based on the same evaluation and experience as mentioned for 22 Cr duplex. 2.3 Normal Carbon Steel (CSNT), not impact tested Materials: As listed in TR2000 EC master material component piping class CSNT including MDS and SST: Pipes: A106, API 5L PSL1 E, A672 C60 Pipe fittings: A234 WPB 1) Forging: A105 Plates: A516 gr60, A516 gr70 1) A672 C60 standard specifies 0.3 mm under tolerance. When TR2000 uses 0.3 mm under tolerance in wall thickness calculations the pipe fitting must be specified accordingly. This is done by both calling off and marking the item ASME B16.9-U03. The associated MDS clarifies that the material requirements are to the referenced ASTM standard; only the tolerances for the wall thickness is changed. Allowable stress Allowable stress as listed in Table A-1 of ASME B31.3 for all materials listed. Maximum operation temperature: 400 C or limited to Table A-1 of ASME B31.3 if lower. Minimum design temperature: According to Table A-1 and Chapter III, Materials, of ASME B31.3 Special low temperature limitation: In order to use A105 according to table A-1 down to -29 C the following is required for all sizes: Normalising heat treatment Minimum forging ratio 4.1 Welding neck of flange according to TR2000 flange material data sheets Cold bending of pipes to allow -29 C is restricted to a bend radius not less than 3D (3 times the pipe outside diameter). Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 3 of 14
ASTM A105 welded components, A106, and A234 WPB to include long formula for the chemical composition: CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15 <= 0.43 Flange standard: ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Rating according to Group 1.1 material in ASME B16.5 2.4 High Temperature Carbon Steel (CSHT11) not impact tested Materials: As listed in TR2000 EC master material component piping class CSLT including MDS and SST: Pipes: A335 P11, A739 1 ¼ Cr Pipe fittings: A234 WP11 Forging: A182 F11 Plates: A387 11 Allowable stress Allowable stress as listed in Table A-1 of ASME B31.3 for all material listed. Maximum operation temperature: 570 C or limited to Table A-1 of ASME B31.3 if lower. Minimum design temperature: According to Table A-1 and Chapter III, Materials, of ASME B31.3. This also applies for valve housing material. Flange standard: ASME B16.5 and ASME B16.47 series A and B Rating according to Group 1.9 materials in ASME B16.5 2.5 Low Temperature Carbon Steel (CSLT), impact tested Materials: As listed in TR2000 EC master material component piping class CSLT including MDS and SST: Pipes: A333 gr6, API 5L X52, A671 CC60 and CC70 Pipe fittings: A420 WPL6, A860 WPHY X52 1) Forging: A350 LF2, A694 F52 Plates: A516 gr60, A516 gr70 1) A671 CC60 and CC70 standard specifies 0.3 mm under tolerance. When TR2000 uses 0.3 mm under tolerance in wall thickness calculations the pipe fitting must be specified accordingly. This is done by both calling off and marking the item ASME B16.9-U03. The associated MDS clarifies that the material requirements are to the referenced ASTM standard; only the tolerances for the wall thickness is changed. Allowable stress Allowable stress as listed in Table A-1 of ASME B31.3 for all material listed, except: A860 WPHY X52 and A694 F52 which use the same as for API 5L X52. Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 4 of 14
Maximum operation temperature: Minimum design temperature: 400 C or limited to Table A-1 of ASME B31.3 if lower. 46 C according to Charpy test requirement in the MDS, or according to Table A-1 and Chapter III, Materials, of ASME B31.3 if lower. Flange standard: ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Rating according to Group 1.1 material in ASME B16.5 2.6 AISI 316 type material Materials: As listed in TR2000 EC master material component piping class 316 including MDS and SST: Pipes: A312, A358 Pipe fittings: A403 1) Forging: A182 Plates: A240 1) A358 standard specifies 0.3 mm under tolerance. When TR2000 uses 0.3 mm under tolerance in wall thickness calculations the pipe fitting must be specified accordingly. This is done by both calling off and marking the item ASME B16.9-U03. The associated MDS clarifies that the material requirements are to the referenced ASTM standard; only the tolerances for the wall thickness is changed. Allowable stress Allowable stress as listed in Table A-1 of ASME B31.3 for all material listed. Maximum operation temperature: Minimum design temperature: 500 C or limited to Table A-1 of ASME B31.3 if lower. In saliferous atmosphere, based on evaluation, the material is limited to 60 C when exposed to such environment over time to reduce risk for stress corrosion cracking. According to Table A-1 of ASME B31.3. Note that the material is specified with solution heat treatment. Flange standard ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Rating according to Group 2.2 material in ASME B16.5. 2.7 6Mo S31254 material Materials: As listed in TR2000 EC master material component piping class 6MO including MDS and SST: Pipes: A312, A358 Pipe fittings: A403 1) Forging: A182 Plates: A240 Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 5 of 14
1) A358 standard specifies 0.3 mm under tolerance. When TR2000 uses 0.3 mm under tolerance in wall thickness calculations the pipe fitting must be specified accordingly. This is done by both calling off and marking the item ASME B16.9-U03. The associated MDS clarifies that the material requirements are to the referenced ASTM standard; only the tolerances for the wall thickness is changed. Allowable stress: T [ C] 20 50 100 115 200 300 S [N/mm 2 ] 200 200 200 200 171 153 This is based on the lower ultimate tensile stress and yield as given from VDM for UNS SN08926 and AVESTA UNS S31254. The lower value of these are used. UNS N08367 is higher strength material. The basis is lower of R m /3, Re 0.2 /1.5 or 90% of Re t0.2 Maximum operation temperature: 300 C Minimum design temperature: -101 C Note that the material is specified with solution heat treatment. Flange standard ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B. Rating for Class 150: According to Group 1.2 material in ASME B16.5 Rating for Class 300 and higher: Up to and including 150 C Group 1.2, from 200 C Group 1.1 This is based on the same evaluation and experience as mentioned for 22 Cr duplex. 2.8 High strength austenitic UNS S34565 material Materials: As listed in TR2000 EC master material component piping class 34565 including MDS and SST: Pipes: A312, A358 Pipe fittings: A403 1) Forging: A182 Plates: A240 1) A358 standard specifies 0.3 mm under tolerance. When TR2000 uses 0.3 mm under tolerance in wall thickness calculations the pipe fitting must be specified accordingly. This is done by both calling off and marking the item ASME B16.9-U03. The associated MDS clarifies that the material requirements are to the referenced ASTM standard; only the tolerances for the wall thickness is changed. Allowable stress: Allowable stress as listed in Table A-1 of ASME B31.3 for all material listed. Maximum operation temperature: 427 C Minimum design temperature: -101 C Note that the material is specified with solution heat treatment. Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 6 of 14
Flange standard ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Rating according to Group 1.2 material in ASME B16.5 This is based on the same evaluation and experience as mentioned for 22 Cr duplex. 2.9 Titanium gr 2. Materials As listed in TR2000 EC master material component piping class TITAN including MDS and SST: Pipes: B861, B862 Pipe fittings: B363 Forging: B381 Plates: B265 Allowable stress According to B381 and B265 gr 2 material listed in Table A-1 of ASME B31.3 for all material. Maximum temperature: According to Table A-1 Minimum temperature: According to Table A-1 Typical application: Below 150 C Flange standard ASME B16.5, NORSOK L-005/5 and ASME B16.47 series A and B Class 150: Up to 50 C: Rating according to Group 1.1 material in ASME B16.5 At 100 C: 15 bar Class 300: Up to 50 C: Rating according to Group 1.1 material in ASME B16.5 At 100 C: 35 bar This is based on the same evaluation and experience as mentioned for 22 Cr duplex 2.10 Bolting Note that when ASME specifies 50 F which is -45.5 C, tradition has been to round it to 46 C A193 B7 bolts: The bolts are used to 46 C without impact testing according to ASME B31.3 table A-2 up to and including 2 ½, and 40 C above this size. A194 2H nuts: The nuts are used to 46 C according to ASME B31.3 table A-2 without impact testing. Certificates Certificates according to EN10204 type 2.2 is used for standard flange bolting listed in ASME B16.5 Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 7 of 14
2.10.1 Flange and clamp connector bolting Flange and clamp connector bolting are not regarded as primary bolting, and the above bolting section can be used. Loss of one bolt do not result in fatal loss of integrity of the connection under pressure. The clamp connections have at least two bolts at each side. One bolt has the capacity to carry the pressure load and forces on the clamp connection. They are pre stressed typically not more than 50% of yield. 2.11 Low temperature limits in ASME Chapter 323.2.2 Low temperature limits, Listed material in ASME applies. This also includes figure 323.2.2A and 323.2.2 B. 3 Design 3.1 Occasional variation of increased pressure and temperature ASME B31.3 allows for the piping to be exposed to temperature and pressure over the design in periods as defined in ASME B31.3 302.2.4 (f). Statoil uses this allowance according to the requirements in ASME. In order to use this allowance it must be based on the evaluation that it is overall cost effective also considering process operation limitations. Typical example may be: When PSHH can be set high enough compared to normal operating condition to avoid operating limitation. In such cases design condition may be at the PSHH if considerable saving in piping material are achieved. Shut-in pressure of well stream is considerably higher than normal operating conditions Shut-in pressure of pumps and compressors Equalising pressure Pressure surge, e.g. water hammer These are examples only and cases are evaluated based on their feasibility. Further 322,6.3 (b) and (c) of ASME with respect to PSV set pressure must be included in the evaluation, also noting that note 13 in (c) of the 322.6.3 is met. The allowable pressure and temperature over design is also applicable for valves. However, valves that are required to be operated in such situation must be evaluated fit for the purpose. The duration of the exposure over design, 302.2.4 (f) (1) and (2), should be used as nominal values. There are no scientific justification to a specific time without consideration of condition of exposure and materials. It is only a philosophy which has been adopted in ASME and practiced with good experience. With this in mind, logging of time should not be required, unless in special cases. Statoils philosophy is that the nature and knowledge of the exposure of time should be evaluated and grouped within the time frames in ASME. 3.2 Use of materials with reduced metal ductility, for cases with low stress ratio (Carbon steel and Duplex materials) ASME B31.3 allows use of piping below impact test temperature (with reduced ductility) for design cases where the stress level is lower than what s needed to risk a brittle fracture, ref. 323.2.2, and Table 323.2.2. The philosophy is also recognised in other standards, e.g. EN 13480 and 13445, and NORSOK M-001. Statoil may use this allowance in accordance with ASME requirements based on the evaluation that it is overall cost effective also considering process operation limitations. (Typical example may be a blow down situation where the combination of several occasions could cause low temperatures at end of system depressurisation). Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 8 of 14
To further support this policy, Statoil got additional quality control to ASME requirements: - Charpy testing of base materials - Metallographic testing - NORSOK M-650 qualification of special materials (applicable for Duplex grades) 3.3 Bending of pipes Bending of pipe can be done according to the ASME 304.2.1 Pipe bends with thinning of the extrados and thickening of the intrados. 3.4 ASME B16.9 fittings Verification of strength ASME B16.9 fittings are acceptable based on burst test according to the standard and as accepted in ASME B31.3 3.5 Unlisted components Components calculated or verified according to ASME B31.3 304.7.2 is acceptable. 3.6 O-lets Stress intensification factor O-lets are historically been the Bonney Forge design expected to be reflected in ASME B31.3. A number of different manufacturers have introduced their designs on the market. Stress intensification factor in bending (inplane, outplane) for these are typically not developed. When they are not known stress intensification factor according to stub in with branch diameter according to o-let diameter at the header may be used. Statoil has now developed our own o-let standard, described in relevant MDS es. 3.7 Equations for wall thickness calculation Calculation of wall thickness is according to equation listed in ASME B31.3. Lame s equation (equation for thick cylinder) has previously been listed and is still intended to be used. Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 9 of 14
App A Pressure rating A.1 General Pressure rating first used when TR2000 (L-SP-200) was introduced was the ANSI B16.5 1981 metric version. The table and graphs below shows this compared with ASME B16.5 1996 including 1998 addenda. The 1996 issue is in Imperial units only. The table below shows interpolation of Imperial units to corresponding pressure and temperature (bar, C) in the 1981 issue. The table and graph shows that they corresponds with deviations only as a result of conversion between the units. Further ASME B16.5 2004 now list metric results. The 2004 issue still shows minor deviation for the relevant materials, which may be result of rounding decimal numbers. Thus, smaller deviations may exist, especially for valve rating that was first established based on the 1981 issue. 22 Cr duplex and 6Mo materials have been used in Statoil with pressure rating as mentioned in section 2 since 1992 with good experience. In later years ASME B16.5 has given pressure rating for these materials, group 2.8 in the table below, which is generally lower rating than used by Statoil. Still Statoil are using these materials in gr. 1.2 (partly for 6Mo) because they are stronger materials than the lower material strength of listed gr. 1.2 material, e.g. A182 F2 (A182 F2 is listed as gr. 1.7 rating, but at the relevant temperatures it is the same as gr. 1.2). Calculation to ASME B31.3, which is based on allowable stress, will result in higher pressure capacity for the above mentioned material than for A182 F2. Statoil will continue to use the rating as stated in section 2 of this document for the relevant materials. Statoil uses a modified geometry of the welding neck of the ASME B16.5 flanges. In ASME the hub angle is limited to maximum 45. This result in a long cylindrical part of the welding neck. Through the TR2000 flange material data sheets, Statoil limits this length, L, hence improving the strength of the flange. ASME B31.3 (ASME VIII 2) calculation of the flanges is a more accurate verification of the flange capacity than is determined by ASME B16.5. It accounts for the geometry, the variation in gasket types etc. Note that relevant wall thickness according to the material strength is used. The calculation example shows a calculation result for D x (S31803, 22C duplex material) at 100 C using rating gr. 1.2 (103.1 bar). The neck length L specified by Statoil is used. It shows that all sizes have the pressure capacity with good margin. The 24 size has the lowest margins. This size is then compared using different parameter: First the D x (S 31803) maximum capacity is calculated (117 bar) using the same cylindrical neck length (L= 30 mm). Then the calculation is repeated using ASME B16.5 maximum length (L= 47.25 mm) resulting a reduced maximum pressure capacity (93.5 bar). The previous calculation used RTJ gasket in 316 sst. Repeating the calculation using Spiral Wound (SW) gasket reduces the maximum pressure capacity to 49.5 bar. Calculation using SD x (S37250, 25 Cr duplex) and ASME L=47.25 mm result in a maximum pressure of 95 bar. Calculation using the A182 F2 material that is listed in a pressure rating equivalent to gr. 1.2 - still using the ASME L - result in a pressure capacity of 89.5 bar. The calculation demonstrates that the higher strength material (D x, SD x etc.) should be rated according to the rating gr. 1.2 as determined by Statoil. Although it is rated lower in ASME B16.5, it demonstrates that pressure capacity of material in ASME B16.5 (A182 F2 in this example) that are listed equivalent to gr. 1.2 (1.7) rating has less pressure capacity then material such as D x, SD x even if they are rated at lower pressure in ASME B16.5. Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 10 of 14
With the Statoil geometry of the flanges, and our experience to use the higher strength material (also same as sealing rating value) we will continue to use this rating as described in section 2 without further need of calculations for each type of material. Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 11 of 14
A.2 Pressure rating to ASME B16.5 Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 12 of 14
A.3 Flange calculation to ASME B31.3 Piping Class DD200 with pressure rating to group 1.2 material for Class 600 rating. Material 22 Cr duplex (D x) UNS S31803: SH - longitudinal hub stress SR - radial flange stress ST tangential flange stress In the following the pressure capacity of the DD200 KRI piping class is calculated for the 24 size which is the size having the lesser pressure capacity. Additionally calculation is made for flange neck L = 47.25 as accepted in ASME B16.5 (Statoil specify maximum L = 30 mm). Also calculation using different gasket and different material are shown, ref table below: Classification: Internal Status: Draft Expiry date: 2010-12-01 Page 13 of 14
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