Sturtevant Richmont 10191, Руководство пользователя

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Chapter 4 - Power Tool Testing Overview
Types of Power Tools
Power tool types may be broken down by basic categories: the means by which they are
powered, the means by which they apply torque, and the means by which torque application
stops. The breakdown of possible combinations appears as below:
Power Source Torque Sensing Shutoff Type
Pneumatic Clutch Clutch
Electric Switch Switch
Hydraulic Pressure Valve
None None (Manual)
The miscellaneous combinations of these three characteristics is what creates the variety of
tools offered on the market. The means by which they are combined, and the way the
design is executed, determines the best means of calibrating the particular tool.
Tools Appropriate and Inappropriate for Testing on Torq-Tronics ®
Impact tools are not to be tested on the
Torq-Tronics ®
family of testers. Doing so will
invalidate the tester warranty and probably damage the tester.
All other types of power tools may be tested on
Torq-Tronics ®.
Stall, clutch, and valve,
and pulse tools may be tested with good results. There will be differences among the types
in technique used to obtain accurate results, but accurate and repeatable results may be
obtained with all of them.
Power Tool Testing Approaches
In general, there are two basic approaches that can be employed in testing power tools: cor-
relative, and tool or tool family specific. These techniques can also be combined to provide
the most cost-effective result for your facility. Each approach has advantages and disadvan-
tages, and the one best for you may not be the same as the best one for the next plant.
Correlative approaches are those that rely on the correlation of the test result (torque),
obtained from a standardized method of testing the tools on the tester, with the actual torque
obtained in use on the joint.
Example
Power tool brand X, serial number 1234, is producing a consistent and acceptable 42 - 48
inch-pounds of torque on the hard joint on assembly Q. This is known from recent audits
and test results on the joint. The tool consistently produces test results of 50 - 56 inch-
pounds on the tester when used with the joint simulator emulating a hard joint and using
Filter 4. Since it is known that a consistent offset of -8 inch-pounds (15% lower on joint