Q & A: Are there Any Special Load Test Requirements for a 50 Ton Crane?

3 comments

by  on May 14, 2012

 Q-&-A-chat

Kyle asks the following question about load testing:

A  company I work with conducts a special lift twice a year where they lift 100,000 lbs. with a 50 Ton crane.  Are there any special requirements as far as load testing, inspections or OSHA requirements that need to be considered when doing this lift?  If so, could we get them in writing?

Tom answers:

Since 100,000 lbs. is 50 Tons, and the capacity of their crane is 50 tons, nothing special is required. They can legally do this all day long as many times as they want (within the CMAA Class of the crane).

On the other hand, if a crane owner wants to lift a load that exceeds the rated capacity of the crane, that owner may do so twice in a 12 month period.  ASME B30 standards refer to this as a “Planned Engineered Lift.”   The requirements can be found in the appropriate ASME B30 Standard, Section three (3). Please review and follow the standards as published.

To summarize, the following conditions must be met:

1.  Review the service/maintenance history of the crane.

2.  A Periodic Inspection must be conducted just prior to the lift and immediately following the lift.

3.  This type of lift is restricted to powered cranes and hoists rated at 5 tons or greater.

4.  The load shall not exceed 125% of the rated load of the crane or hoist.

5.  This event is limited to twice in a twelve-month period.

6.  A written report, documenting all aspects of the event, must be  placed on file. Documentation is very important and needs to be emphasized.

{ 3 comments… read them below or add one }

Wayne August 13, 2012 at 11:48 am

Thank you for the clarification Tom.

Tom Reardon Tom Reardon July 27, 2012 at 1:26 pm

Wayne,
Thank you for your question.
If your question is related to an Overhead and Gantry Crane, the standard and paragraph you refer to would be ASME B30.2 -1.14.5. If an Overhead Hoist (Underhung) is the focus of your inquiry, ASME B30.16-1.2.9 is applicable. The wording in each of these standards is identical; “If hooks are of the swiveling type, they should rotate freely.”

As you can see from the wording, swiveling hooks are not mandatory, as evidenced by the statement “If hooks are of the swiveling type,” with If being the operative word. These same standards also do not mandate that hooks “rotate freely under load”. The standards make no reference to “under load“. The wording is clear that a swiveling hook is optional and the free rotation is also optional as demonstrated by the word “should”. Mandatory provisions of the standards are indicated by use of the word “Shall”.

You are correct concerning the use of a thrust bushing vs. bearing in Shawbox hoists with capacities below 3 TONS. A thrust bearing is an available option on all 800 series hoists and is standard on hoists rated at 3 TONs and above.

Tom Reardon
Crane Training Manager

Wayne July 26, 2012 at 2:59 pm

If the standards state that a load hook must rotate freely under load, how can liftech justify using a thrust bushing instead of a thrust bearing on the 800 series shawbox that will not allow the hook to rotate under load?

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