API RP 934-E:2010 pdf download
API RP 934-E:2010 pdf download.Recommended Practice for Materials and Fabrication of 11/4CR-1/2Mo Steel Pressure Vessels for Service Above 825°F (440 °C).
NOTE The J-factor is not plicable to these alloys, and an X-bar bmil has been adopted as a means of restflct’ng the concentration of elements that conlflbute to reheat cracking of the steel
The chemistry restrictions described above along with other aspects of this RP are designed to provide the steel with resistance to the reheat cracking phenomenon described in API 938-A.
5.4 Heat Treatment
Jl product forms shall be annealed, normalized and tempered (N&T) or quenched and tempered (Q&T) to meet the required mechanical properties, For thickness >2 in, (50 mm), O&T may be required to meet fracture toughness specifications for the steel. Annealed steel and lower Class levels should be specified for applications involving high temperature service where the primary failure mechanism is creep rupture. For equipment exposed to cyclic service and where fatigue Is an miportant factor the use of N&T or Q&T beat treatment and Ngher class levels may be more appropriate
5.5 Mechanical Properties
5.5.1 LocatIon of Test Specimens
Test specimens for establishing the tensile and impact properties shall be removed Iron, the following locations:
a) Plate—From each mother-plate with the same heat treatment, transverse to the rolling direction In accordance with SA-20 at the standard test locations and at the ½T location. When permitted by the applicable product specification, coupons for all tests shall be obtained from the ‘12T location only. If required, 112T specimens shall be used for hot tensile tests.
NOTE if multiple plates are ait from one motherplate only one set of specimens from the motherplate is required.
b) Forging—From each heat transverse to the major working diection In accordance with SA-1 82 or SA-336, and test specimens shall be taken at 1f2T of the prolongation or of a separate test block A separate test block, if used, shall be made from the same heat arid shall receive substantially the same reduction and type of hot working as the production forgings that it represents and shall be of the same nominal thickness as the production forgings. The separate test forging shall be heat treated in the same furnace charge and under the same conditions as the production forgings
C) Pipe—From each heat and lot of pipe, transverse to the major working direction In accordance SA 530 except that test specimens shall be taken from 1/2T.
55.2 TensIle Test Requirements
5.5.2.1 Tensde testing of plates and forging matenals shall comply with the applicable code(s) and the following additional requiements.
5.5.2.2 Test coupon shall be heat treated to represent the maximum post-weld heat treatment per 3.1.6.
5.5.2.3 Tensde properties at room temperature shall meet the requirements of the applicable code(s).
5.5.3 impact Testing Requirements
Charpy V-notch (CVN) impact testing shall be performed for all 11I4Cr-tl2Mo steel material used for pressure containing components except bolting. CVN impact tests shall comply with the applicable code(s) and the following additional requwements.
a) Test coupons from forgings shall be oriented transverse to the major dwection of metal flow.
7.3.2 Dehydrogenation Heat Treatment (DHT)
The DHT shall be performed at a minimum metal temperature of 570 °F (300 °C) for duration of one hour minimum.
7.4 Production Testing of Base Metal Welds
7.4.1
Chemical Composition of Production Welds
7.4.1.1 The chemical composition of the weld deposit representing each dfferent welding procedure shall be checked by either laboratory chemical analysis or by using a portable analyzer of equivalent accuracy and precision.
7.4.1.2 The chromium and molybdenum content of the weld deposits shall be within the ranges specifed in ASME Section I, Part C for the specified electrodes.
7.4.2 Hardness of Weld Deposit and Adjacent Base Metal (heat affected zone hardness)
7.4.2.1 After final PWHT (see 7.6) hardness determinations shall be made for each pressure-etaining weld using a portable hardness tester.
7.4.2.2 Each hardness test location result shall be the average of three impressions at each test location. The test locations shall include weld metal and base metals adjacent to the fusion line on both sides. Hardness values of all three locations shall be reported.
7.4.2.3 Hardness values shall not exceed 225 HBW.
