Stamping technology

Technical conditions of cold stamping parts

1 Subject content and scope of use

1.1 This technical specification stipulates the technical requirements, test methods, inspection rules and packaging of the metal and non-metal, plate and profile materials used in the company’s products for cold stamping processing methods (hereinafter referred to as stamping parts). , Storage and transportation and other general requirements.

1.2 This technical proposal does not apply to stamping parts processed by precision blanking methods.

1.3 This technical condition is valid for reference in product drawings and other technical conditions, and the marking method is that cold stamping parts comply with OCYD.599.000

2 Reference standards.

JB4378 Metal cold stamping parts structural elements

GB/T13914-92 Tolerance of stamping parts

GB188-89 General Theory of Tolerance and Fit Standard Tolerance and Basic Deviation

GB1804-92 Non-injected tolerance of general tolerance linear dimension (Guide: New invention: ejection mechanism for demoulding of stamping parts)

GB4129-85 burr height of stamping parts

GB2828-87 Sampling procedure and sampling table for batch inspection by attributes

3 counting requirements

3.1 The raw materials used in stamping parts should meet the requirements of the product drawings, and should have a quality warranty or physical and chemical test report, which can ensure that the materials meet the timely requirements of the standard. When there is no quality certificate or other reasons, it should be entrusted with An authoritative third-party organization conducts physical and chemical tests.

3.2 Shape and size.

a. The shape and size of the stamping parts should meet the requirements of the product drawings.

b. The shape and size of stamping parts should pay attention to the process restrictions. The design of sheet metal should follow the stipulations of JB4378-87 'Structural Elements of Metal Cold Stamping Parts'. For metal profiles, pipe fittings and non-metallic plates, please refer to c Refer to this standard.

c The shape and dimensional tolerances of stamping parts meet the requirements of GB/T13914-92 'Dimensional tolerance of stamping parts'. Non-metallic plates can also refer to this standard. At the same time, the shape and dimensional tolerances of stamping parts can also be implemented in GB1800-79 'General Tolerance and Fitting Standard Tolerance and Basic Deviation' Article 31 and GB1804-92 'Unmarked Tolerance of General Tolerance Linear Dimensions'.

3.3 Surface quality.

Except for the punching surface, the surface condition of the stamping parts is required to be consistent with the materials used. During the molding process, slight stretch wrinkles and small surface unevenness are allowed. The surface treatment of stamping parts, such as rust removal, pickling, degreasing, phosphating, painting, oxidation, metal coating, etc., shall be specified in the technical requirements of the product drawings.

3.4 The limit value of the burr height of metal stamping parts should meet the requirements of GB4129-85 'Burr height of stamping parts

3.5 Sections of blanking parts.

When it has nothing to do with quality and assembly, the inclination of the section will not be assessed. Allows natural stepping and tilting on the blanking die and punching punch side.

3.6 Bend

Under the condition of not affecting the assembly quality, the bending part of the stamping part is allowed to have slight deformation, such as the edge protruding, the thickness of the material changes, and the hole is slightly elongated. When the edge is not allowed to protrude, process measures can be added before bending To solve the problem, for the bending of rod-shaped parts, a very slight twisting phenomenon is allowed.

3.7 Flanging

Slight cracks are allowed at the edge of the sheet metal stamping parts that need to be flanged, but the flanging of the sheet metal used for functional threads shall not affect the effective thread diameter and tolerance.

3.8 For the top piers, the surface of the top piers should be smooth, and no cracks and serious defects affecting the surface quality are allowed.

3.10 The tolerances of unmarked ordinary threads are in accordance with GB197-81 'Ordinary Thread Tolerances and Fits' T-level accuracy.

3.11 Some stamping prices that require welding, heat treatment, shaping and other process treatments. If it is considered that the process size needs to be increased, the process size is allowed to temporarily deviate from the product design size, but after processing, it must be ensured to meet the design requirements.

4 Inspection method

4.1 The raw materials shall be inspected in accordance with the inspection procedures for raw materials entering the factory, and shall meet the requirements of the product drawings.

4.2 Stamping parts are divided into self-made parts and external parts. Self-made parts should be inspected according to the process size of the cold stamping process card of this product, and external parts should be inspected according to the inspection card of the part, and should have Material warranty and product qualification certificate.

4.3 The precision inspection of stamping parts is to use tools, clamps and measuring tools that can ensure the measurement accuracy to inspect the size, shape, position and accuracy of the stamping parts.

5 Inspection rules

Inspection type test, periodic test and routine test.

5.1 Type test: carried out with the product

5.2 Periodic test: carry out with the product

6.3 Routine test

5.3.1 During the 3.1 inspection, if the quality assurance certificate is not available, the inspection department shall entrust a third-party organization to carry out the rationale test according to the material standard.

5.3.2 When conducting the inspections in Articles 3.2-3.11, a sampling plan shall be carried out according to GB2828-87 'Batch-by-Batch Inspection Counting Sampling Inspection Procedure and Sampling Inspection Table'. The general inspection level is Level II, and the qualified quality level is 2.5. For safety The inspection of the parts is carried out in accordance with the regulations of the inspection card.

6 Packaging, transportation, storage

6.1 The packaging should ensure that the stamping parts are not damaged during the transportation process. The name, specification, code, quantity, manufacturing unit, and date of the stamping parts should be marked on the box, and a certificate of conformity should be attached.

6.2 The stamping parts must be protected from moisture, deformation and rust during transportation to ensure the quality.

6.3 Stamping parts should be stored in a clean, ventilated, dry, and non-corrosive warehouse, and should not be placed directly on the ground.

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