Types and Uses

TM 9-243 TYPES AND USES A wrench is a tool specially designed to tighten or loosen nuts, bolts, studs, and pipes. Wrenches are forged from steel alloy to prevent breakage. There are many differ- ent types of wrenches. Each type has its own use. By using the properwrench for the task to be done, you will not break the wrench, damage the equipment, or cause personal injury. The following section is intended to give you information on the different wrench types. OPEN-END WRENCHES The engineer’s double open-end wrench has different size openings on each end. This type of an arrangement permits a smaller number of wrenches to complete a set. The engineer’s double open-end wrench is also used to reach behind or below blind surfaces. All open-end wrenches have open jaws on one or both ends of the wrench. Most jaw openings are offset from the shank portion of the wrench by 15 degrees. The wrench length is determined by the size of the jaw opening. Some of the more common types of open-end wrenches and their uses are listed below. The construction wrench combines the open-end jaw with a long tapered shank providing a wrench/alignment punch combination. The construction wrench is used in the building trades and on heavy objects which require alignment before fastening. The engineer’s single open-end wrench has a long smooth shank providing the user with a better gripping surface. It is used to reach behind or below blind surfaces. 25-2