Giant Williams WRENCH

[apolk13]

I am trying to find info about a GIANT Williams wrench I purchased. 
It is 42 and 1/2 inches long with a 4+" opening on one end and it weighs about 65 to 70 pounds. It seems to be painted black.
I was told it was used on an Oil Rig or on the Railroad.  Based on what I have found so far, it seems to be post 1924 (based on the logo)
The first picture I have attached is not the wrench, but to show the logo.  It has the Diamond W logo and the "Forged in US"
The second image is the wrench.

[Papaw]

Welcome to Tool Talk!
That IS a large wrench!
Start here-- http://home.comcast.net/~alloy-artifacts/williams-supercompany.html

[wvtools]

It should have a number on the other side of the head.  It is probably a 20B, 20, or 20A with an opening of 4 1/2, 4 5/8, or 5 inches.  In the 1960 catalog, there were 5 wrenches larger than the No. 20A, with the 22B having a 7 5/8 inch opening and 52 inches long.

[bird]

am I allowed to ask how much you payed for it? welcome to tool talk!
cheers,
bird.

[Papaw]

Jenny, that was posted in January and he hasn't come back since.

[bird]

Jenny, that was posted in January and he hasn't come back since.

I guess I should have welcomed him sooner!!!!
cheers

[Billman49]

My uncle was the engineer on steam tugs working out of Swansea harbour, in Wales UK. About 1965 we went out into the Bristol Channel in a force 10 gale to bring a ship into harbour. When towing all hands had to be below deck, in case the hawser broke, so I spent my time in the engine room..... There were spanners there over 8 ft long to work on bolts on the engine...

A few years later I hitched a lift back to where I was serving ny apprenticeship, and was picked up by a Royal Navy articifer instructor - we got to talking about ships, engines and spanners. He told be these big spanners were torqued up using a weight suspended from a rope, and either dropped or swung onto the end of the spanner. By working out the inertia of the weight, and multiplying by the length of the spanner, the torque could be worked out....

Who needs a torque wrench for bolts over 2" in diameter???

And if you need more info ref tightening nuts onto bolts, read: http://www.appliedbolting.com/pdf/lessons_from_the_field-lesson_1.pdf

and if that 'rocks your boat' try: http://www.consultorescpm.com.mx/consultorescpm/attachments/article/204/53.pdf

or even more technical: http://www.lifetime-reliability.com/free-articles/precision-maintenance/Summary_of_Bolt_Tensioning.pdf