Standard Interpretations - (Archived) Table of Contents|
November 15, 1989
|To:||John B. Miles Jr.|
|From:||David C. May|
|Subject:||Request for Interpretation of ANSI B30.11|
Is it proper design for the loading on a hoist to exceed the rate load capacity to activate the upper travel limit device.
During an inspection of a manufacturing facility in New Hampshire a Yale KEL 2-ton chain hoist was observed to be equipped with a load limiting clutch. The clutch prevents a loading above 175% of the rated hoist load. The load clutch is also used as the upper limit travel device. When used as the upper limit travel device, a safety factor of less than 5 to 1 is encountered.
This monorail hoist system is covered under ANSI B30.11 "Monorail Systems and Underslung Cranes which references ANSI B30.16 "Overhead Hoists" as the standard to use to cover hoists.
Mr. Robert Rersinger, Chairman of B30.16 (717) 741-4863, was contacted. He agreed the safety factor is not being maintained but believes there may still be adequate strength. Apparently other units also operate in this manner. He explained that a written request to ASME would be needed to get an official reply. Their address is listed below.
If further information is needed please contact David Berard or David May of this office.
345 East 47th Street
New York, NY 10017
|Standard Interpretations - (Archived) Table of Contents|