Torque wrenches, also known as a lug wrench, are a variety of tools for loosening or tightening bolts with a square drive. They are available in different types and sizes and range from basic models to professional grade. If you are planning to buy a torque wrench, it is essential that you know your needs and requirements then put them into consideration while making the purchase.
This article discusses different types of torque wrenches.
Types of Torque Wrenches
Slipper Torque Wrench
A slipper torque wrench has a spring loaded mechanism that holds the inner spindle in place. It is designed to automatically adjust once the desired amount of applied torque is reached allowing you to loosen or tighten more effortlessly.
A slipper torque wrench is not designed to be used in a continuous intermittent motion. You should only apply the necessary amount of torque for loosening or tightening the bolt and maintain that torque until you remove the tool from the fastener.
A torque stick has a fixed scale that is marked in foot-pounds. It shows the amount of torque to be applied and therefore enables you to tighten or loosen more accurately. It is designed to prevent over tightening.
The torque stick can be used for both commercial and industrial applications. However, it remains best suited for controlling the amount of torque while loosening bolts.
Torque Wrench Adapters
Many of the modern vehicles in use have hexagonal fasteners that require a special tool for removal and installation. Torque wrenches are available with adapters for such fasteners.
A torque wrench adapter is a steel disc that has a hexagonal recess on the side. Before using the tool, you need to fix an adapter into it which then allows you to loosen or tighten the bolts efficiently and accurately as per the desired application without damaging them or their threads.
Handle Torque Wrench
A handle type torque wrench contains an outer casing with either a calibrated dial for setting up the torque value or a digital display screen for easy reading.
Many of these display the accuracy range, maximum and minimum torque values along with some other features that make them convenient to use.
A handle type torque wrench is not suitable for heavy construction work but it serves well as a precision tool for tightening or loosening small hardware bolts.
Beam Torque Wrench
A beam type torque wrench contains a hardened chrome plated beam that measures the amount of torque applied to its handle. They come in manual and electronic models though the latter is more expensive.
Depending on the manufacturer, some types of beam type torque wrenches come with an accuracy range from 0 to 12 foot-pounds while others can measure up to 3000 foot-pounds.
The electronic type is convenient for complex applications as it shows the torque applying range and the current value of applied torque.
A beam type torque wrench has a fixed head that cannot be removed from its handle. It is suitable to use with nuts, thread bolts and other components with right handed threads only. You can also use it in both clockwise and counterclockwise directions.
Electric Torque Wrench
An electric torque wrench is a battery operated tool that offers a lot of convenience as it works without noise.
You can use them in places where no power supply is available or perhaps you need to adjust the torque value frequently when working on projects in different parts of your workplace.
They have triggers and illuminated displays that allow you to see the amount of torque being applied to a fastener. In most cases, the display shows the current torque value as well as the maximum and minimum values that you can set through knobs or buttons.
A wrench that offers an adjustable torque range of from 0 to 1000 foot-pounds is suitable for light duty work like assembling furniture. However, it would not be ideal for heavy duty tasks. In most cases, the adjustable range can be 0 to 2000 pounds though you can find wrenches with a higher torque range as well.
This tool uses electricity from batteries and these can run out of power when you are working on a project that requires frequent changes of torque value. Most models have low battery indicators to indicate the need for changing batteries earlier than expected.
They also save energy as they can be used in place of manual wrenches and no physical effort is needed to change their torque settings.
The electric torque wrench can be a useful tool for various applications such as assembly of furniture, construction and repair work. However, it is unsuitable for heavy duty tasks like repairing car engines or the wheels of heavy vehicles.
Standard Torque Wrench
A standard type torque wrench has a sliding head that you can adjust along the length of its handle as well as a rotating handle.
You can use it for both clockwise and counterclockwise operation of fasteners with right handed threads.
However, you cannot use standard type wrenches on the opposite direction since they have fixed heads that cannot be removed from their handles even if they come in an adjustable wrench model.
Hubless Torque Wrench
A hubless torque wrench comes without a tightening head and instead has a handle fitted with screws. The point where the handle meets its shaft can be adjusted to enable you to work on different projects.
You can measure angles or slots when working on complex components since this is one of the best types of adjustable wrenches available in the market. It is also commonly called a flex head torque wrench.
You can use them for both clockwise and counterclockwise directions of fasteners with right handed threads. However, they are not suitable for left-handed threads.
Mechatronic Torque Wrench
A mechatronic torque wrench offers an adjustable head that you can use not only for normal clockwise and counterclockwise working of fasteners but also on irregular shapes.
You should adjust it to the angle at which you want to hold it while gripping a bolt or nut. It gives an error-free reading since the zero adjuster cannot be removed inadvertently from its handle.
It is suitable for both right and left handed threads, but you should never use it on a broken bolt that has an unthreaded portion. This type of wrench can be used to tighten oversized bolts as well as any other fastener in tight corners.
A mechatronic torque wrench is best suited for industrial applications and it offers a greater accuracy than regular wrenches when you use them on irregular shaped nuts and other fasteners.
This means that you can achieve the right amount of tightened force for more consistent performance in case of machine assembly line work.
This type of wrench is also useful for those working in refrigeration and aerospace industries.
Impact Torque Wrench
An impact type torque wrench comes with a ratchet that makes it useful for use on industrial machinery, automotive vehicles and any other application that requires great force.
Their main function is to break the crank bolts of engines used in aviation. This means that they are usually used in conjunction with air impact guns to help you run out of bolts that are too tight or stripped.
You’ll require a lot of physical strength to use these wrenches since they provide great force when you squeeze the trigger and give a good amount of torque when you release it. You should not remove their protective caps until you need to use them since they could easily cause damage to other parts of your body.
A screwdriver will not help you run out a stripped bolt since it does not provide sufficient force needed for this task. You can use an impact wrench in case the heads of bolts become broken or curled due to over tightening or if you have removed them without using the right amount of force.
You can use impact type wrenches in the opposite direction of right handed threads since they have heads that allow you to do so. However, you must also ensure that your hands are properly placed when using them on left-handed threads in case the bolt ends up breaking inside the thread hole.
This means you should not squeeze the trigger while there is a chance that the bolt will jump and hit any of your body parts.
Click Torque Wrench
A click torque wrench is also called an electronic wrench since it uses a gauge to measure the amount of force applied while tightening a screw.
It has an adjustable head that you can place on fasteners with right and left handed threads for ideal results. You just need to calibrate them once before use so as to ensure that their accuracy remains intact every time you use them.
A click torque wrench gives an audible click at the point where you have reached the desired torque value for a fastener. This means that it is easy to read and more convenient than using a regular type of wrench since you do not need to rely on your sense of touch to know when you have applied enough force on a nut or bolt.
A click torque wrench is suitable for mechanics, automobile repair experts and all types of artisans who need to use nuts and bolts to keep machines in place.
It offers a higher accuracy than most wrenches that you can buy from stores since it has a special mechanism inside its head that keeps the desired force intact throughout use. They can easily determine if a bolt has been tightened to the right amount based on its color.
Hydraulic Torque Wrench
A hydraulic torque wrench is an ideal tool for industrial purposes. It usually comes in a long shaft that you can turn to apply force on nuts and bolts. You just need to use it in conjunction with an air compressor pump when working on large fasteners, particularly those used on commercial power plants.
This type of wrench uses a liquid lubricant to make it easy for the user to turn the wrench shaft. You just need to direct compressed air into the wrench shaft and leave it in position for as long as needed before you can retract it.
A hydraulic torque wrench comes with a large gauge that allows you to measure applied force while working on any type of bolts or nuts.
There are two common types of hydraulic wrenches that you can find in stores. The first type has an extension feature, allowing it to hold a significantly large amount of force inside the torque shaft. It is mainly used when tightening or loosening very large bolts on commercial power plants and machinery.
A second type comes with a fixed length wrench shaft that does not provide any extension mechanism. These wrenches come with a built-in pump that allows the user to generate pressure needed for tightening or loosening bolts without any additional device.
Torque Wrench Usage Tips
Using a torque wrench will help you save time and energy when tightening nuts or bolts. However, it is easy to use them incorrectly if you do not follow the right steps as given below:
- Always read the instructions that come with your wrench before use or know their ideal ranges so as to ensure that they are in good working condition all the time.
- You should make sure you hold the wrench with both hands before using it if you want to achieve correct results.
- Always use your torque wrench for fasteners that are within their capacity as given in product packaging or accompanying documentation.
- You should also check them after long term use to ensure that they remain accurate.
- Avoid applying too much pressure on the wrench when tightening since this may break off bolts and damage your tool.
- It is best to keep a second torque wrench as backup in case you need one during work. This allows you to use it quickly if you manage to damage the first one while using it or drop it on concrete, for example.
- You should always calibrate your torque wrench at least once a year for accuracy.
- Stored should be in a clean, dry place to prevent any damage from rust and allow easy retrieval when needed.
Can a torque wrench be used in plumbing?
Yes, you can use them for that purpose. Just make sure that you check the wrenches specifications and capacities before using one on this type of job to avoid causing leaks or bursting pipes.
What is the ideal length for a torque wrench?
The ideal length of your torque wrench will depend on the type and size of bolts you need to tighten or loosen when working. The ideal length will also be determined by how far you can comfortably reach the target area.
How do I prevent rust from damaging my torque wrench?
Always store your torque wrench in a dry place with no moisture so as not to allow it corrosion. You can also wipe it with a light oil like WD-40 before storing it to prevent damage from moisture.
How can I calibrate my torque wrench?
You should check the calibration of your torque wrench after purchasing it or after long term use. You should also re-calibrate it at least once every year. For this you need an accurate, digital scale or an electronic gauge.
How can I test the accuracy of my torque wrench?
You should perform a “Torque Test” to check the accuracy and calibration of your torque wrench at least once every year.
To do this: Tighten a nut 64 times with your wrench without stopping on full turns. Then remove the nut and weigh it on an accurate scale. The weight should not vary more than 2 percent from the initial weight.
If your wrench is low in accuracy, you can adjust its settings to match an accurate torque range.
A torque wrench is a useful tool in mechanics, which can be used to help repair and maintain the precision of various mechanical components.
By learning about the different types and their usages, you will be able to make an informed decision on your next purchase or repairs.