Failure of Components Although the Causes Are Simple & Well Documented.
Abstract
For most of the materials commonly used in machinery, the static, fatigue and other design properties have been well-studied and documented. Yet, very common and simple oversights are made in choosing the right material and the correct design for an application, leading to premature failure of components in pieces of equipment. This paper will present two failures caused by inadequate design and improper material selection. (1) Failed pawls in hand operated winches for ladder hoist: A pawl finger is used in the winch which engages in-between the teeth of two gears to lock the winch in place when weight is on the ladder extension. Occasionally, the pawl sustains failure. Determination of the cause, as well as recommendations for improvements will be discussed. (2) Failed "Power Lock" Tapered Ring: This device was designed to fasten a sprocket to a shaft without the use of keyways. The power lock consisted to two tapered rings bolted together with six bolts, wedged against an outer and inner ring. One of the tapered rings fractured during a bench test. The root cause analysis and recommendations for prevention is provided.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1998
- Accession Number
- ADA348336
Entities
People
- Fahmida Hossain
- James J. Scutti