The Elsmar Cove Wiki More Free Files The Elsmar Cove Forums Discussion Thread Index Post Attachments Listing Failure Modes Services and Solutions to Problems Elsmar cove Forums Main Page Elsmar Cove Home Page
Google
  Web Elsmar.com
*Please be aware that SOME RECENT forum threads may not yet be indexed by Google.

View Full Version : Special Processes


Mike48
28th February 2002, 04:57 PM
:bigwave:

As defined by QS9K in element 4.9, pg. 35, would torque be considered a special process?

db
28th February 2002, 07:15 PM
Mike

Whether torque is considered a “special process” would depend greatly on what you mean. For example, if you are tightening a bolt to a specified torque, it can easily be verified using a torque gauge. If you are using a torque-to-yield bolt, where the bolt is stretched, neither a torque wrench or angle meter can be used. I would think that this could qualify as a “special process” because as far as I know there is no way to test this type of fastener without loosing it and starting over (which will damage the bolt)

I think this is correct, hopefully your question is covered by one of the two types.

M Greenaway
1st March 2002, 04:38 AM
Torque in itself cannot be considered a special process as it is not a process, it is a physical characteristic.

The process of tightening something to a required torque is only a special process if you cannot validate the required torque has been achieved.

The use of a simple torque wrench will overcome this problem.

gpainter
1st March 2002, 08:13 AM
To add to this ,if a customer requires a certain lbs of torque. then the wrench will need to be calibrated.

M Greenaway
1st March 2002, 08:39 AM
gpainter

or the process qualified, i.e. established by test that a certain number of turns with a spanner produces the required torque (if the torque isnt that crtical - i.e. wheel nuts). In instances of a more precise torque then a claibrated torque wrench would be the ideal method.

You may also have a subsequent test that will confirm of the torque has been achived, i.e. hydrostatic pressure testing of a valve head assembly.