Repair 7

A torque wrench is a hand tool that has a gauge indicating specific torques being applied to a bolt or nut. They are helpful in the the construction and repair of auto engines, where specific fasteners have specific torques. Too much or too little torque may cause the engine to emit noise. Michigan Industrial Tools is one company that makes these instruments. Most torque wrenches operate in a similar manner.

Instructions

1

Check your repair manual for the specific torque of the bolt you are tightening.

2

Loosen the fastening bolt at the bottom of the wrenchs handle by turning it counter-clockwise.

3

Rotate the handle until it matches the desired torque measurement.

4

Tighten the fastening bolt by turning it clockwise to secure the handle.

5

Place the head of the torque wrench over the head of the nut. Hold the head of the wrench with one hand and the handle with the other.

6

Turn the wrench until the bolt is tightened. When it reaches the specified torque, the wrench will make an audible click and no longer tighten.

Under-torqued hardware may loosen during use, while over-torqued hardware may fail or damage the assembly it is attached to. Torque wrenches provide the means to measure safe, exact tightening force on hardware to prevent such occurrences. These precision tools must be routinely calibrated and certified for continued reliable operation.

Purpose

Like any tool, torque wrenches wear over time. Depending on the type, they may contain tiny gears, teeth, springs, gauges and other moving parts. The more the tool is used, the quicker these parts need to be inspected and replaced.

Frequency

The recommended calibration frequency of torque wrenches varies by manufacturer. Six months to one year is the prevalent calibration cycle. The International Organization of Standards (ISO) 6789:2003 does not use calendar time to recommend calibration, instead providing a calibration standard of 5,000 cycles.

Procedure

Torque wrench calibration and certification involves a thorough inspection and test of the tool. Precise pressure is applied to the wrench while its effectiveness is measured. If the tool does not indicate proper torque at the specified pressure, it is cleaned, repaired and retested.

Using a normal socket with an impact wrench is no different than using an impact socket with an impact wrench. The difference between the two sockets is the thickness and hardness of the material used to make them. Obviously, the impact socket is made to withstand the punishment of the impact wrench, but for projects that require less torque to either attach or remove a fastener, a normal socket will do just fine.

Instructions

1

Attach the air compressor hose to the impact wrench by pulling back the compression ring on the female end of the hose and inserting the male fitting on the handle of the impact wrench into the hose connection and releasing the compression ring when the male fitting is seated.

2

Choose the appropriate size normal socket that will fit the nut or bolt being removed. Align the square hole in the socket with the square drive on the impact wrench and push the square drive of the impact wrench into the square hole of the socket.

3

Remove the nut or bolt by placing the exposed end of the socket over the nut or bolt and pressing the trigger of the impact wrench. Make sure that the impact is set in the reverse position before pressing the trigger. If the nut or bolt is being tightened, place the socket attached to the impact wrench over the nut or bolt and press the trigger while the wrench is in the forward position. Refer to the impact wrench manufacturers manual for directions.