New Lifting/Spreader Beam Load Test or Not? 5

[bgunner01]

Our Engineering Department designed (using AISC 9th Ed.) a new spreader beam for lifting a specific size and weight of sea-land container. The device was fabricated of A50/A36 structural shapes and plates and controlled (QC inspected) welds were used per AWS D1.1. Allowable working load for the device is 33.6 Tons.

In the past (on much smaller capacity rigging fixtures) we have justified NOT load testing because the devices were considered an "engineered item" designed by qualified engineers using proven empirical design data, and fabricated using the same highly qualified personnel and procedures we use on high pressure nuclear piping.

My question is: Do we need to load test this device before use? We don't load test building structures before we use them. Since we don't have means on site to load test such a large capacity device, it will need to be shipped out to a vendor if testing is required. How do you handle such a problem at your facility?

Thanks so much for any recommendations you can offer...!

 

[LSPSCAT]

I have tested numerous devices for various shipping containers. I now forget the exact agencies, however, I believe shipping (ocean going vessels) are required to test these per DIN standards and the Bureau Veritas for insurance and international regulations. Bureau Veritas sends an inspector to the site to view and witness such tests. Containers are quick and easy to load test if you have access to the necessary counterweight.

In the U.S., design should be per ASME B30.20 for Below the Hook lifting devices and once again you should test to 125% of the rated load. (This is worded as "should" not required.) If you are doing this for any type of agency that is involved in nuclear work I would be suprised if they did not require you to perform and certify a load test.

In testing lifting devices for nuclear containment vessels this same procedure was also followed.

 

[bgunner01]

I should elaborate a bit more. The device will be used at midwest power generation facilities, including a PWR nuclear facility - but only in the Turbine Generator Building and in only non-nuclear safety related areas. It will be used primarily for ramp-up/ramp-down maintenance activities during refueling outages.

 

[rb1957]

so the "sea/land container" was a references to a comparable load and not an application.

IMHO (not worth 2c) if the loading is well defined (i think it is) and the loadpaths are well defined (i think so) and the calcs are well understood (i think so) then you shouldn't need to test.

if you have a heathy MS and/or included a sufficiently large Factor of Safety in your calcs, i think a test is unnecessary. If your first lifts are below capacity then you'll get some experience with it and judge how well it performs.

on the other hand, maybe your labour code says you have to !?

 

[LSPSCAT]

As stated, my experience with supplying any lifting beam or device to the nuclear power industry has always required a lift test prior to commencing work along with PE stamped drawings. It may or may not be overkill, but if the test arrangement can be made reasonably cheap/quick, then it is cheap insurance. (This included some very heavy picks 300 TNS)

It may or may not be a requirement in your case, typically it will be at the Owners discretion.

 

[topsisu]

For designs in the US, you should get ASME BTH-1-2008 ($53 - 52 pages) "Design of Below-the-Hook Lifting Devices". This is also an ANSI standard. It was written to suppliment B30.20.

BTH-1 covers the structural design of spreaders and includes variable factor of safeties based on usage. The safety factors are more strict than AISC. This standard first came out in 2005 and will be updated next year.

 

[JStephen]

It is my understanding that in general, OSHA requires lifting beams to comply with the ASME standard, and that standard requires load testing.

 

[LSPSCAT]

ASME B30.20 states "should test" - not "required"; I checked again so please correct me if I am wrong. I have always presented this to owners this to leave them the option.

 

[BAretired]

Does the Factor of Safety take into account the dynamic nature of the load? It has an allowable working load of 33.6 Tons. Is that a static load?

It seems to me that the static failure load should be about 100 Tons, is that about right?

BA

 

[csd72]

You could load test insitu by lifting the required test load 2" above the ground. That way if it does fail the load does not fall far.

Would recommend this only on solid ground though.

 

[topsisu]

According to OSHA 1926.2519(a)(4) lifting accessories must be proof tested. See the following link.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10686

In this interpretation letter, OSHA says essentially all rigging equipment used for material handling must be proof tested to 125% of rated load.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=25192

 

[bgunner01]

The OSHA interpretation letter linked in Topsisu's 7/12/10 post spells out quite clearly what I will conform to.

THANK YOU to all who responded -- What a great resource this site is!!