API RP 934-E-2018 pdf free download

API RP 934-E-2018 pdf free download.Recommended Practice for Materials and Fabrication of 1¼Cr-½Mo Steel Pressure Vessels for Service above 825 ˚F (440 ˚C).
3.1.7 master plate The term used by ASME SA-20/SA-20M to describe starting plates that are subdivided into multiple plates. 3.1.8 maximum PWHT Specified heat treatment (aggregate temperature and time) of test specimens to simulate the maximum heat- treatment exposures on the vessel. The test coupons (initially with the same austenitizing and tempering heat treatment as the as-supplied material) are heat treated at a temperature and time that simulates all fabrication heat treatments above 900 °F (482 °C). This includes the intermediate stress relief (ISR), all PWHT cycles, a PWHT cycle for possible shop repairs, and a minimum of one extra PWHT for possible future use by the purchaser. Typically, the ISR and PWHT cycles are aggregated into one single equivalent heat treatment, as discussed in the note below. Dehydrogenation heat treatments (DHT) do not need to be included, as they are at too low of a temperature to affect material properties. NOTE To determine the equivalent time at one temperature (within the PWHT range) of heat steps outside the PWHT range, the Larson-Miller Parameter formula may be used; results are to be agreed upon by the purchaser and fabricator. At the time of any future repairs, it is the owner’s responsibility to determine any changes in strength and toughness properties of the material that may have occurred from high-temperature service. The results achieved by the maximum PWHT testing may not be representative of the actual mechanical properties after exposure to service temperature. 3.1.9 minimum PWHT Specified heat treatment (aggregate temperature and time) of test specimens to simulate the minimum heat- treatment exposures on the vessel. The test coupons (initially with the same austenitizing and tempering heat treatment as the as-supplied material) are heat treated at a temperature and time that simulates the minimum of all fabrication heat treatments above 900 °F (482 °C). This typically includes the ISR, if any, and one PWHT cycle.
3.1.12 temper embrittlement The “reversible” reduction in toughness due to a metallurgical change (primarily impurity segregation at grain boundaries) that can occur in some low-alloy steels as a result of long-term exposure in the temperature range of about 650 °F to 1070 °F (343 °C to 577 °C). This change causes an upward shift in the ductile-to-brittle transition temperature as measured by Charpy impact testing. Although the loss of toughness is not evident at operating temperature, equipment that is temper embrittled may be susceptible to brittle fracture during start-up, shutdown, or hydrotesting after weld repair. 1¼Cr-½Mo and 1Cr-½Mo steels are considered to be less susceptible and to have less of a shift than 2¼Cr-1Mo alloys. 3.2 Acronyms For the purposes of this document, the following acronyms apply. CVN Charpy V-notch DHT dehydrogenation heat treatment FN ferrite number HAZ heat-affected zone HBW Brinell hardness with tungsten carbide indenter HV Vickers hardness LCD low creep ductility LMP Larson-Miller parameter MDMT minimum design metal temperature MT magnetic particle testing MTR material test report NDE nondestructive examination PQR procedure qualification record PT penetrant testing PWHT post-weld heat treatment RT radiographic testing SS stainless steel UT ultrasonic testing WPS welding procedure specification 4 Design of Pressure Vessels and Heat Exchangers 4.1 Design and Manufacture Design and manufacture shall conform to the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 or Division 2. The latest edition of the Code, including addenda effective through the date of the purchase agreement, shall be used.
4.2 Coverage of Design Issues Design issues are typically covered by a manufacturer’s design report that shows compliance of the design with the user’s design document; ASME Code strength calculations, drawings, and local stress analysis for extra loads; and special design requirements, if required. This recommended practice is not intended to cover design issues, other than those below. a) The design thickness (T) shall not include any allowance for extra thickness provided either as corrosion allowance or as a corrosion-resistant liner, such as weld overlay or cladding. b) Weld seam layouts shall provide that all welds are accessible for NDE, such as RT, UT, MT, and PT, both during fabrication and in service. The use of external attachments that cover weld seams should be avoided, and require purchaser approval.