GB/T 37683-2019 English PDF (GB/T37683-2019)

GB/T 37683-2019: Large gear and girth gear forgings - Technical specification
Delivery: 9 seconds. Download (& Email) true-PDF + Invoice.
Get Quotation: Click GB/T 37683-2019 (Self-service in 1-minute)
Historical versions (Master-website): GB/T 37683-2019
Preview True-PDF (Reload/Scroll-down if blank)

GB/T 37683-2019
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 77.140.85
J 32
Large gear and girth gear forgings -
Technical specification
ISSUED ON: JUNE 04, 2019
IMPLEMENTED ON: JUNE 04, 2019
Issued by: State Administration for Market Regulation;
Standardization Administration of the PRC.
Table of Contents
Foreword ... 3 
1 Scope ... 4 
2 Normative references ... 4 
3 Ordering requirements ... 5 
4 Manufacturing process ... 5 
5 Technical requirements ... 6 
6 Inspection rules and test methods ... 12 
7 Acceptance and quality certification ... 16 
8 Marking and packaging ... 17 
Large gear and girth gear forgings -
Technical specification
1 Scope
This Standard specifies the ordering requirements, manufacturing process,
technical requirements, inspection rules and test methods, acceptance and
quality certification, and marking and packaging of large gear (including gear
shaft) and girth gear forgings.
This Standard applies to the ordering, manufacture, and inspection of large
gear (including gear shaft) and girth gear forgings.
2 Normative references
The following documents are indispensable for the application of this document.
For the dated references, only the editions with the dates indicated are
applicable to this document. For the undated references, the latest edition
(including all the amendments) are applicable to this document.
GB/T 223 (all parts) Methods for chemical analysis of iron, steel and alloy
GB/T 228.1 Metallic materials - Tensile testing - Part 1: Method of test at
room temperature
GB/T 229 Metallic Materials - Charpy Pendulum Impact Test Method
GB/T 230.1 Metallic materials - Rockwell hardness test - Part 1: Test method
(scales A, B, C, D, E, F, G, H, K, N, T)
GB/T 231.1 Metallic materials - Brinell hardness test - Part 1: Test method
GB/T 4340.1 Metallic materials - Vickers hardness test - Part 1: Test method
GB/T 6394 Metal - Methods for estimating the average grain size
GB/T 10561-2005 Steel - Determination of Content of Nonmetallic Inclusions
- Micrographic Method Using Standards Diagrams
GB/T 37400.15-2019 Heavy mechanical general technical specification -
Part 15: Nondestructive test of steel forgings
3 Ordering requirements
3.1 The purchaser shall specify in the ordering contract the forging name,
executed standard, material designation, quantity supplied, delivery state, and
the corresponding technical requirements and inspection items specified by the
supplier and the purchaser.
3.2 The purchaser shall provide the forging ordering drawings.
4 Manufacturing process
4.1 Melting
Steel for forgings shall be melted in an electric furnace or converter and refined
outside the furnace. With the consent of the purchaser, other melting methods
which guarantee quality may also be used.
4.2 Forging
4.2.1 The nozzle and riser of the ingot shall have sufficient removal, to ensure
that the forging product has no shrinkage cavity, looseness, severe segregation,
and other harmful defects.
4.2.2 Forgings shall be forged and formed on forging equipment with sufficient
capacity, to ensure that the entire section of the forging is thoroughly forged and
evenly organized.
4.3 Heat treatment
4.3.1 After the forging is forged, the supplier shall perform normalizing and high
temperature tempering treatment.
4.3.2 The normalizing temperature of carburized steel forgings shall be higher
than the carburizing temperature.
4.3.3 The supplier may, according to the material designation of forging and the
ordering technical requirements, perform performance heat treatment or
carburizing heat treatment.
4.4 Machining
4.4.1 Forgings shall be roughed or semi-finished prior to quenching and
tempering or carburizing heat treatment.
4.4.2 The dimensions, tolerances, and surface roughness of the forgings shall
5.3 Hardness
When forgings are only required to be accepted according to hardness, the
hardness deviation of the same forging does not exceed 40 HBW. However,
when the mechanical properties of forgings are required at the same time, the
absolute value of hardness is not used as the basis for acceptance.
5.4 Nondestructive testing
5.4.1 General requirements
Forgings shall be free of defects such as white spots, cracks, folds, shrinkage
cavities, severe segregation which affect the use performance and surface
quality.
5.4.2 Ultrasonic testing
Forgings shall be subjected to ultrasonic testing before tooth punching after
roughing and heat treatment. The testing results within the range of 20 mm or
1.5mn (when the modulus mn>12) below the tooth and root shall meet the
requirements of the quality grade II of Table 1 of GB/T 37400.15-2019. The
testing results of the remaining positions shall meet the Grade IV requirements.
5.4.3 Magnetic particle testing
When the ordering technical agreement or the ordering contract has the
requirement for magnetic particle testing, the magnetic particle testing shall be
carried out by the purchaser. The testing method and acceptance criteria shall
meet the requirements of the ordering contract or the ordering technical
agreement.
5.5 Metallographic structure
5.5.1 Grain size
When the inspection of grain size is required, it shall be indicated in the ordering
contract. The inherent grain size of carburized steel shall not be coarser than
Grade 5.0.
5.5.2 Nonmetallic inclusions
When it is required to inspect nonmetallic inclusions, it shall be indicated in the
ordering contract. The A, B, C, and D nonmetallic inclusions of forgings shall
not exceed Grade 2.5.
deformation, the direction of the tensile and impact samples shall be axial
(longitudinal). When the ordering technical agreement or ordering drawing
requires a tangential or transverse sample, the test results of the
mechanical properties shall be lower than the specified values in Table 3
(longitudinal) by the percentage specified in Table 5.
b) For ring forgings, disc forgings, and the forgings mainly based on upsetting
deformation, the direction of the tensile and impact samples shall be the
direction of the main deformation, i.e. the tangential direction
(circumferential direction).
6.2.3 Test methods
6.2.3.1 The tensile test shall be carried out in accordance with the provisions of
GB/T 228.1.
6.2.3.2 The impact test is carried out in accordance with the provisions of GB/T
229.
6.3 Hardness inspection
6.3.1 The hardness inspection of forgings shall be carried out in accordance
with the provisions of GB/T 231.1. The hardness inspection of hardened
samples shall be carried out in accordance with the provisions of GB/T 230.1.
Vickers hardness inspection shall be carried out in accordance with the
provisions of GB/T 4340.1.
6.3.2 At least two places shall be measured at the end face of the girth gear
forging and about 1/4 of the diameter from the outer surface; the two places are
180° apart. If the forging is larger than ϕ3000 mm in diameter, at least four
places shall be measured, each at a distance of 90°. The hardness of gear or
gear shaft forgings shall be measured at four places on the outer surface to be
tooth-punched, 90° apart.
a) When performing a V-notch impact test, if the arithmetic mean of a set of
impact samples is not lower than the specified value, and one of the
values is not less than 70% of the specified value, retest may not be
performed. When the above requirements are not met, a set of three
impact samples may be taken in the adjacent part of the previous sample
for retesting. The arithmetic mean of the two sets of samples shall not be
lower than the specified requirement. The number of single values below
the specified value shall not exceed two. Only one single value is allowed
to be less than 70% of the specified value;
b) When performing a U-notch impact test, if a certain test result is
unqualified, double quantity of samples may be taken in the adjacent part
of the previous sample for retesting. The retest results of the two samples
shall conform to the regulations.
6.6.3 If the inspection of mechanical properties is unqualified due to white spots
and cracks in the sample, retest shall not be conducted.
6.7 Reheat treatment
When the inspection result of any mechanical property of the forgings is still
unqualified, reheat treatment may be carried out; re-sampling shall be carried
out for test. The number of reheat treatments shall not exceed two at most. The
number of tempering is not limited.
7 Acceptance and quality certification
7.1 Acceptance
7.1.1 The supplier shall provide the necessary conditions for purchaser’s
acceptance personnel, for the purchaser’s acceptance personnel to carry out
the on-site inspection work. The purchaser’s inspection personnel shall not
hinder the production of the supplier.
7.1.2 The purchaser has the right to select certain test items of forgings for
acceptance. During the acceptance inspection or the subsequent processing or
inspection, if it is found that the forgings do not meet the supplementary
technical requirements specified in this Standard and in the ordering contract,
the purchaser shall promptly notify the supplier; the two parties shall negotiate
to resolve.
7.2 Quality certification
The supplier shall provide the purchaser with a quality certification. The quality
certification shall at least include the following:
GB/T 37683-2019
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 77.140.85
J 32
Large gear and girth gear forgings -
Technical specification
ISSUED ON: JUNE 04, 2019
IMPLEMENTED ON: JUNE 04, 2019
Issued by: State Administration for Market Regulation;
Standardization Administration of the PRC.
Table of Contents
Foreword ... 3 
1 Scope ... 4 
2 Normative references ... 4 
3 Ordering requirements ... 5 
4 Manufacturing process ... 5 
5 Technical requirements ... 6 
6 Inspection rules and test methods ... 12 
7 Acceptance and quality certification ... 16 
8 Marking and packaging ... 17 
Large gear and girth gear forgings -
Technical specification
1 Scope
This Standard specifies the ordering requirements, manufacturing process,
technical requirements, inspection rules and test methods, acceptance and
quality certification, and marking and packaging of large gear (including gear
shaft) and girth gear forgings.
This Standard applies to the ordering, manufacture, and inspection of large
gear (including gear shaft) and girth gear forgings.
2 Normative references
The following documents are indispensable for the application of this document.
For the dated references, only the editions with the dates indicated are
applicable to this document. For the undated references, the latest edition
(including all the amendments) are applicable to this document.
GB/T 223 (all parts) Methods for chemical analysis of iron, steel and alloy
GB/T 228.1 Metallic materials - Tensile testing - Part 1: Method of test at
room temperature
GB/T 229 Metallic Materials - Charpy Pendulum Impact Test Method
GB/T 230.1 Metallic materials - Rockwell hardness test - Part 1: Test method
(scales A, B, C, D, E, F, G, H, K, N, T)
GB/T 231.1 Metallic materials - Brinell hardness test - Part 1: Test method
GB/T 4340.1 Metallic materials - Vickers hardness test - Part 1: Test method
GB/T 6394 Metal - Methods for estimating the average grain size
GB/T 10561-2005 Steel - Determination of Content of Nonmetallic Inclusions
- Micrographic Method Using Standards Diagrams
GB/T 37400.15-2019 Heavy mechanical general technical specification -
Part 15: Nondestructive test of steel forgings
3 Ordering requirements
3.1 The purchaser shall specify in the ordering contract the forging name,
executed standard, material designation, quantity supplied, delivery state, and
the corresponding technical requirements and inspection items specified by the
supplier and the purchaser.
3.2 The purchaser shall provide the forging ordering drawings.
4 Manufacturing process
4.1 Melting
Steel for forgings shall be melted in an electric furnace or converter and refined
outside the furnace. With the consent of the purchaser, other melting methods
which guarantee quality may also be used.
4.2 Forging
4.2.1 The nozzle and riser of the ingot shall have sufficient removal, to ensure
that the forging product has no shrinkage cavity, looseness, severe segregation,
and other harmful defects.
4.2.2 Forgings shall be forged and formed on forging equipment with sufficient
capacity, to ensure that the entire section of the forging is thoroughly forged and
evenly organized.
4.3 Heat treatment
4.3.1 After the forging is forged, the supplier shall perform normalizing and high
temperature tempering treatment.
4.3.2 The normalizing temperature of carburized steel forgings shall be higher
than the carburizing temperature.
4.3.3 The supplier may, according to the material designation of forging and the
ordering technical requirements, perform performance heat treatment or
carburizing heat treatment.
4.4 Machining
4.4.1 Forgings shall be roughed or semi-finished prior to quenching and
tempering or carburizing heat treatment.
4.4.2 The dimensions, tolerances, and surface roughness of the forgings shall
5.3 Hardness
When forgings are only required to be accepted according to hardness, the
hardness deviation of the same forging does not exceed 40 HBW. However,
when the mechanical properties of forgings are required at the same time, the
absolute value of hardness is not used as the basis for acceptance.
5.4 Nondestructive testing
5.4.1 General requirements
Forgings shall be free of defects such as white spots, cracks, folds, shrinkage
cavities, severe segregation which affect the use performance and surface
quality.
5.4.2 Ultrasonic testing
Forgings shall be subjected to ultrasonic testing before tooth punching after
roughing and heat treatment. The testing...