problem identifying thread 1

[gieter]

I have an impeller with an internal thread. A thread pitch gauge for Whitworth 55° 11G-5/8 fits fine. The inner diameter is 123.8 mm or 4.874" (4 8/7?). I searched the internet for Whitworth thread tables but they all stop at smaller diameters.

Can anyone give a hint?

Thanks in advance,

 

[MotorVib]

Did you check the Machinery's Handbook? I didn't see anything they go from 4.5 to 5.0 but I did check the metric tables.

At that odd size it might be made to a print.

Chris

Chris

"In this house, we obey the laws of thermodynamics." Homer Simpson

 

[unclesyd]

Here is aite that might help.

http://www.sizes.com/tools/thread_whitworth.htm

 

[berkshire]

gieter
Check out a British Standard Pipe Parallel thread 4 1/2" dia. The inner diameter is 122.772mm according to the table, which is about 1mm away from where you are now. This is assuming a full threadform.
Here is a link to a thread table

http://mdmetric.com/tech/thddat7.htm

B.E.

 

[gieter]

B.E. Thanks for your valuable information. This is the first link to a thread table with larger diameters. I'm sure I can make use of it.

Sorry for the late reply. I was on hollydays.