Torque wrenches are used when the tightness of a screw or a bolt is crucial to the item it is on and how that item operates. A torque wrench is required by car mechanics when they are working on different aspects of the engines. The torque wrench was invented in 1918 by Conrad Bahr while he was employed by the water department of New York City.

When Conrad Bahr was working for the water department in New York City he saw a need to invent a tool that would prevent workers from over-tightening the bolts on the water mains and on the steam pipes when they were making repairs. The tool he devised was the torque wrench and it allows a person to measure the amount of torque they are applying and to match the amount to the specific amounts required on the device they are working on.

Torque wrenches are manufactured by most of the large tools suppliers. Beta, Craftsman, Makita, DeWalt, and Snap On are some of the big names in these types of mechanical devices. You can usually buy them in stores that carry tools designed for the repair of automobiles, and you can also buy them online. Many people prefer the online stores because their prices are lower than the prices of many of the retail outlets in the local malls.

There are different types of torque wrenches as well as different manufacturers. The most common and most simple torque wrench is the beam type that is made up of a long lever arm that connects the handle to the wrench head. This main shaft will bend in response to the applied pressure. There will be a smaller bar attached in the same manner but the difference will be the smaller bar is stationary and is never subjected to torque so it keeps a constant position in respect to the head. This is called the indicator bar.

There are also torque wrenches known as the:
• Deflecting Beam torque wrench can be almost impossible to use in automotive applications because the scale may not be read directly. This creates a large chance for error.
• The click type torque wrench is considered to be more precise when they are calibrated correctly. These are considered to have break-downs or failures more frequently than the beam type does.
• The “no hub” torque wrenches are primarily used on soil pipe couplings. This wrench has a handle that is shaped like a T. It has a one way ratchet and clutch that is pre-set to a designated torque.
• The electronic torque wrench has a torsion rod connected to a strain gauge that allows for the reading to be made.
• The programmable electronic versions allow the operator to set them to apply a determined amount of torque dependent on the specifications for the device they are working on.
• The Mechatronic Wrenches work like the click type does but the measurement is seen as a digital reading.

The torque wrench http://www.betafer.it/en-1029-torque-wrenches.html was invented in 1918 in New York City by a city employee that saw the need for torque wrenches http://www.betafer.it/en-13-torque-wrenches-and-multipliers.html to keep employees from over tightening the bolts on steam pipes and water mains.