Laura Gross Wrenches September 08th, 2018 - 15:35:38
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.
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."
You will not find an auto repair shop, an automotive training course or even an auto mechanic school that is not well stocked with a wide variety of combination wrenches. When it comes time to do car repairs or other basic mechanical jobs, the first tool in your kit should be the combination wrench. Solid, basic, sturdy and dependable the combination wrench doesn't have moving parts and is designed to withstand impacts on even the most demanding jobs.
Torque wrenches are precision tools and should be treated as such. Although most micrometer wrenches have a reversible ratchet head, they really should not be used as a ratchet, and especially not as a breaker bar. Most people who break their torque wrenches do so by trying to loosen an overly tight bolt with it. This overly stresses the internal mechanism, causing it to break, especially if the micrometer isn't set to a higher torque value than the pressure that is being applied.
Three of the most common wrenches found in American homes are the pipe wrench, the adjustable wrench and the combination wrench.