Quality Inspection Requirements And Content Of Heat Treatment Of Parts

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Exterior:

1. The parts should be cleaned, and the process and operation shall be ensured to comply with the process regulations, and the first appearance inspection shall be carried out by visual inspection or low magnification.

Mirror to observe whether there are cracks, burns, bumps, corrosion, pitting and rust on the surface of the parts.

2. For important or easily cracked parts, non-destructive testing, sandblasting and other methods should be carried out for general inspection.

Distortion:

1. For shaft parts, use tops or shaped blocks to support both ends, and use a dial indicator to measure radial runout.

2. For plate-shaped or sheet-shaped parts, use a feeler gauge to check the flatness of the parts on the inspection platform.

3. Use dial gauges, vernier calipers, plug gauges, inner diameter dial gauges, thread plug gauges and ring gauges to inspect the outer circle of parts such as sleeves and round parts.Dimensions of inner hole, thread, etc.

Hardness:

1. Carry out the calibration of the hardness block to remove the surface oxide scale, decarburized layer and burrs, etc., and no obvious surface is allowed.Machining marks such as abrasion, knife marks, etc.

2. According to the specific requirements of the part, the size and thickness of the tested part, etc. as the basis for selection, select the required hardness tester for inspection. Vickers Hardness Tester.

The hardness test should be no less than 3 points in each place, and the unevenness is within the required range.

3. The parts should be stable on the worktable, and the plane detection shall prevail. If the hardness of the cylindrical surface or the hardness of the curved surface, the spherical surface, etc. can only be tested unconditionally, the correction value should be added.

4. For those with a special shape and difficult to detect hardness with a normal platform, you should consider choosing or making special fixtures or auxiliary supports, and it is required to ensure the stability and reliability of the parts.

Metallographic:

1. According to process requirements and inspection procedures, inspect as required.

2. For more important parts, when quality problems, process changes, and waste analysis are required for this batch of parts, correct metallography should be carried out.

3. The parts undergoing chemical heat treatment should be inspected for penetration depth, organization and structure, brittleness, etc.

Mechanical Properties:

1. Perform mechanical performance testing according to the performance requirements of the parts, and the interception position and sample size of the sample should meet the relevant regulations.

2. The samples and parts should be the same batch of materials and be treated in the same furnace.

Editor: Frank Lee

Copyright: SIMUWU Vacuum Furnace