Power Tool
Torque Wrench
Torque wrenches are hand tools designed to tighten fasteners to a specified torque rather than simply applying as much force as possible.
Drive Sizes · Types · Use · Articles
Torque wrench drive sizes
Drive size determines socket compatibility and usually corresponds to the scale of fasteners and torque work the tool is intended to handle. The usable torque range is model-specific.
| Drive size | Typical role | Strengths | Tradeoffs |
|---|---|---|---|
| 1/4 inch | Small fasteners and lower-torque work | Compact and suited to smaller sockets | Not intended for larger fasteners |
| 3/8 inch | General light-to-medium fastening | Versatile size with broad socket availability | May not cover higher-torque jobs |
| 1/2 inch | Automotive and larger fasteners | Common choice for higher-torque work | Larger and less convenient for small fasteners |
| 3/4 inch | Heavy equipment and larger fasteners | Built around larger sockets and heavier work | Specialized and bulky for routine tasks |
Torque wrench types
Different mechanisms communicate the target torque in different ways, but every wrench should be used within its stated range and according to its manufacturer instructions.
| Type | How it indicates torque | Typical advantage |
|---|---|---|
| Click | Mechanical click or release at the set value | Simple preset operation |
| Beam | Pointer moves across a scale as force is applied | Direct visual reading with a simple mechanism |
| Digital | Electronic display and signal | Readable settings and feedback features that vary by model |
Using a torque wrench
- Use the fastener torque specification and procedure provided for the equipment being serviced.
- Use a compatible socket and keep the wrench within its stated operating range.
- Apply force smoothly and stop when the wrench gives its specified indication.
- Follow the wrench manufacturer’s instructions for storage, calibration checks, and service intervals.
