Gwendolyn Kelly Wrenches September 08th, 2018 - 06:19:40
Micrometer wrenches are pre-set to the required torque on a vernier scale. An internal spring loaded mechanism measures the torque. When the bolt is tightened to the desired torque it "clicks."
If you are buying a torque wrench for your car, you should buy a 1/2 inch square drive tool, as 3/8 in drive tools only work on lower torque settings (typically below manufacturer's specifications). Adapters are available to reduce the 1/2 inch square drive to 3/8 inch square to fit the more common socket size that most people have.
As everyone who has been through an apprentice program knows, bolts are used in construction, manufacturing, and assembly of almost everything. By having a combination wrench set at the ready, you can show that you have the ability to place or remove a bolt easily and efficiently.
There are two basic types of torque wrenches on the market, what are called "beam" wrenches and "micrometer" wrenches. Beam wrenches count on the built-in flexibility of any material. As torque is applied, the wrench flexes, while another rod, with a pointer at the end, indicates torque being applied on a scale.
Of the two types of torque wrenches, the micrometer wrench is definitely the more accurate. Typically, they are rated as being accurate to four percent of torque set. However, this accuracy can easily be lost if the wrench is not reset to zero before storage. Beam wrenches don't have this possibility of losing their accuracy, but are less accurate right out of the box. The accuracy of these beam wrenches is typically 12 percent, but can be less on higher torque settings, especially if the operator's hand is shaking from the pressure they are applying.