What Is a Torque Wrench Used for and How to Use It Properly?

Have you ever wondered how precision is achieved when tightening bolts and nuts in critical equipment or structures?
The answer lies in a simple but essential tool known as the torque wrench. From the aerospace and aviation industry to automotive repairs, torque wrenches have numerous applications in various industries.

In this article, we will explore different uses of torque wrenches and why we should use it.

Torque Wrench Uses

Torque wrenches are a valuable tool in many industries, especially in those where precise torque specifications are crucial to ensure the safety and reliability of equipment.

Following are some of the specific use cases of torque wrenches by industry.

Automotive

In the automotive industry, torque wrenches are used extensively to ensure that critical bolts and nuts are tightened to accurate torque settings. Here are some common uses of torque wrenches in automotive applications:

• Torquing Wheel Nuts: Tightening lug nuts on car wheels to the manufacturer’s specified torque reading to prevent overtightening or under-tightening, which can cause the wheels to come loose or even cause the brake rotors to warp.
  You can use an impact wrench or a regular socket wrench with a breaker bar to remove the lug nut. But you must always use a torque wrench to do the final tightening of the wheel nut.
• Engine Assembly: Securing engine head bolts to a precise torque setting during an engine rebuild or repair to ensure that the head gasket seals properly and that the engine operates efficiently without leaks or other problems.
• Replacing Spark Plugs: The correct torque setting for the spark plugs is important to ensure that they are properly seated in the engine and to prevent damage to the threads in the cylinder head. Over torquing the spark plugs can cause the threads in the cylinder head to strip, which can result in expensive repairs.
  Note: Do this when the engine is cold because the metal in the cylinder head can expand when it is hot, which can affect the torque reading and result in an improperly tightened spark plug.
• Suspension Bolts: Securing fasteners on a suspension system to the recommended torque during an automotive repair or upgrade to ensure that the suspension functions correctly, which can affect the car’s handling, ride quality, and safety.

Aerospace and Aviation

In the aerospace and aviation industries, precise torque is essential for safety. Torque wrenches are used extensively to tighten bolts on critical components of aircraft and spacecraft. Here are some specific use cases where torque wrenches are used in aerospace and aviation applications:

• Tightening bolts on an airplane engine during maintenance or repair to a specific torque setting to ensure that the engine operates safely and reliably, as an improperly tightened bolt can cause engine failure, which can lead to a catastrophic outcome.
• Securing bolts on a satellite or spacecraft to a specific torque setting during assembly or maintenance to ensure that the spacecraft is reliable and operates correctly in space, where there is no opportunity for repairs.

Construction and Engineering

In construction and engineering, torque wrenches are used to ensure that critical fasteners are tightened to specific torque settings to prevent damage and accidents that can result in serious injuries and fatalities. Here are some typical use cases for torque wrenches in construction and engineering applications:

• Scaffolding: Installing and tightening bolts on a scaffolding structure during construction to ensure that the scaffolding is secure and that workers can safely perform their tasks at height without the risk of collapse or instability.
• Framing: Tightening bolts on a metal frame for a wooden structure during construction, such as a house or a bridge, to ensure that the frame is sturdy and can withstand the stresses and loads it will encounter.
• Large Construction Projects: Tightening bolts on a bridge or other large-scale infrastructure project to a required torque setting to ensure that the structure is secure and can withstand the stresses it will encounter over its lifetime.
• Railroads: Tightening bolts on a railway track to the exact torque setting during construction or maintenance to ensure that the track is stable and can support the weight of the trains that will pass over it.
• Buildings: Tightening bolts on the steel structure of a stadium or arena during construction to a specified torque value to ensure that the structure is safe and can withstand the loads it will encounter during events.

Chemical & Electrical

In the electrical industry, torque wrenches are used to ensure that electrical connections are properly installed and tightened to the required torque values. Here are some specific situations where torque wrenches are used in electrical applications:

• Wind Turbines: Assembling bolts on a wind turbine tower during construction or maintenance to ensure that the tower is secure and can withstand the high winds and other environmental conditions that it will encounter.
  Tightening nuts and screws on the blades of a wind turbine to a specific torque setting during construction or maintenance to ensure that the blades are secure and can rotate efficiently in the wind.
• Installing and tightening bolts on electrical equipment, such as switchgear, solar panels, transformers, and circuit breakers, to ensure that the equipment operates correctly and safely.
• Tightening bolts on a high-pressure vessel used in chemical or petrochemical processing to the exact force to ensure that the vessel can safely contain the high-pressure fluids or gases it is designed to hold.

Manufacturing and Production

In manufacturing and production, torque wrenches are used to ensure that products are assembled to precise specifications. Following are some common torque wrench uses in manufacturing and production applications:

• Heavy Equipment: Tightening fasteners on heavy machineries, such as hydraulic jackhammers, excavators, earth moving equipment or bulldozers, during the maintenance to ensure that the machinery is safe and can operate efficiently, which can impact the productivity and profitability of the project.
• Machining: Fastening workpiece or jigs/fixtures on a machine tool to a specific torque setting to ensure precision and accuracy in manufacturing processes. For instance, clamping a T-bolt and flat clamp to secure a workpiece on a milling machine.
• Sheet Metal Stamping: Here, the cutting and forming dies need to be clamped on the stamping press bed to ensure that the die doesn’t move during stamping operations.
• Injection Molding and Pressure Die Casting: In these molding operations, the material is injected at very high pressure, which can cause the mold to move. It is important to fasten the mold on the machine securely.

Mining and Extraction

In mining and extraction, torque wrenches are used to ensure the safety and reliability of heavy equipment and machinery. Here are some specific use cases for torque wrenches in mining and extraction applications:

• Tightening bolts on mining equipment during assembly or maintenance to ensure that the equipment is safe and can operate efficiently, which can impact the productivity and profitability of the mine.
• Tightening bolts on a mining roof support to the correct torque during installation or maintenance to ensure safety in underground mining operations.

Other Applications

There are many other industries and applications where torque wrenches are used. Here are some additional use cases for torque wrenches:

• Clamping the pressure vessel used in a nuclear power plant to a precise torque reading to ensure that the vessel is safe and can withstand the high pressure and temperature conditions inside the plant.
• Locking a fire hydrant to optimal torque to ensure proper operation during emergencies.
• Tightening bolts on a railway wheel to an exact torque setting to prevent accidents or derailments.
• Assembling fasteners on a crane or other lifting equipment precisely to ensure that the lifting equipment is safe and reliable and can lift and move heavy loads without the risk of failure.
• Locking a bolted joint flange used in the oil and gas industry to a required torque to ensure that the flange connection is leak-proof and can safely contain the high-pressure fluids or gases.

Overall, torque wrenches are a valuable tool in many industries where precise torque specifications are essential for safety, reliability, and compliance with industry standards. By understanding the specific use cases for torque wrenches in various industries, professionals can ensure that equipment is installed and maintained safely and efficiently.

How to Use a Torque Wrench?

Make sure that your torque wrench can handle the minimum and maximum torque range and you have the correct size sockets. The correct procedure for using a torque wrench is explained below.

1. Ensure that the Torque Wrench Is Calibrated

Have you calibrated your wrench recently? If not, calibrating a torque wrench is the first step since this affects the torque accuracy.

Read my guide on how to calibrate torque wrenches easily.

2. Set the Desired Torque

On a click torque wrench, you would rotate the handle knob to set the desired value. Make sure that the required torque and the value set on the wrench are expressed in the same unit.

3. Place the Wrench on the Fastener

After setting the desired torque, always place your wrench securely onto the fastener before applying pressure to avoid any unwanted accidents due to slippage.

4. Start Tightening

Once secure, turn the wrench counterclockwise (assuming that you are working with a right-hand thread) until you hear the clicking sound or beep on digital wrenches. In case you have multiple bolts or nuts, tighten them gradually to ensure that you are tightening them equally.

5. Monitor the Torque Reading

If you are using a digital torque wrench, watch the reading on the electronic display or listen to the clicking sound in the case of a click type torque wrench. You might want to give it one extra push to make sure that the wrench clicked.