JB/T 4727-2010 Low-alloy steel forgings for low temperature pressure equipments
1 Scope
This standard specifies the technical requirements, test methods and inspection rules of low-alloy steel forgings for low temperature pressure equipments.
This standard is applicable to low-alloy steel forgings for low-temperature pressure equipments with design temperature lower than 0°C and design pressure less than 100MPa.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 222-2006 Permissible tolerances for chemical composition of steel products
GB/T 223 Methods for chemical analysis of iron steel and alloy
GB/T 228 Metallic materials - Tensile testing at ambient temperature (ISO 6892:1998(E))
GB/T 229-2007 Metallic materials - Charpy pendulum impact test method (ISO 148-1:2006)
GB/T 4336 Standard test method for spark discharge atomic emission spectrometric analysis of carbon and low-alloy steel (routine method)
GB/T 6394 Determination of estimating the average grain size of metal (ASTM E112:1996)
GB/T 10561 Steel - Determination of content of nonmetallic inclusions - Micrographic method using standards diagrams (ISO 4967:1998)
GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition (ISO 14284:1996)
JB/T 4730.3 Nondestructive testing of pressure equipment - Part 3: Ultrasonic testing
3 Terms and definitions
For the purposes of this standard, the following terms and definitions apply.
3.1
hollow forging
axisymmetric hollow forging with axial length L greater than outside diameter D, as shown in Figure 1a), where, t refers to nominal thickness
3.2
ring forging
axisymmetric hollow forging with an axial length (L) less than or equal to its outer diameter (D), as shown in Figure 1b), where, L and t, whichever is smaller, refers to nominal thickness
3.3
disk forging
axisymmetric solid forging with an axial length (L) less than or equal to its outer diameter (D), as shown in Figure 1c), where, L refers to nominal thickness.
3.4
bowl forging
axisymmetric forging with height H less than or equal to outside diameter D and with concave section, as shown in Figure 1d), where, t1 and t2, whichever is larger, refers to nominal thickness
3.5
neck flange forging
axisymmetric hollow forging with two outer diameters in the axial direction, as shown in Figure 1e), where, t1 and t2, whichever is larger, refers to nominal thickness
3.6
bar forging
solid forging with a circular cross section and an axial length (L) greater than its outer diameter (D), as shown in Figure 1f), where, D refers to the nominal thickness
forging with a rectangular cross section and an length (L) greater than its two side lengths a and b, as shown in Figure 1g), where, a and b, whichever is smaller, refers to nominal thickness
Foreword II
1 Scope
2 Normative References
3 Terms and definitions
4 Order information
5 Technical requirements
6 Test methods
7 Inspection rules
8 Marking and quality certificate
Annex A (Normative) Additional requirements
