Improved magnetic particle inspection of small threaded fasteners
Magnetic particle inspection is required for over 100 types of threaded fasteners used at Bendix Kansas City Division of Allied Corporation. Most are purchased screws and bolts made to AN, MS, and NAS specifications. These specifications invariably require that testing be in accordance with MIL-I-6868E, ''Inspection Process, Magnetic Particle.'' This specification includes directions for magnetization of test objects that are inappropriate for many small parts, particularly for screws and bolts of less than about 8-mm thread diameter. Following those directions is more likely to interfere with the detection of serious defects than to ensure that they will be found. Alternate testing techniques that make it easier to find and correctly interpret defect indications have been developed. A new semiautomatic magnetic particle testing machine for threaded fasteners and other small parts up to 9.5 mm in diameter and 150 mm in length is being built to BKC specifications, with delivery scheduled for April, 1985. Interim procedures using existing equipment have been adopted to improve the reliability of magnetic particle inspection of small fasteners.
- Research Organization:
- Allied Corp., Kansas City, MO (USA). Bendix Kansas City Div.
- DOE Contract Number:
- AC04-76DP00613
- OSTI ID:
- 5950172
- Report Number(s):
- BDX-613-3283; ON: DE86009324
- Country of Publication:
- United States
- Language:
- English
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