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How Much Torque Do I Need in An Impact Wrench?

An impact wrench on the floor

Still using that dated and overworked electric drill of yours? Well, it’s time to ditch it for good. Why do we say this? Because a much better option is available to you—an electric impact wrench.  Known by many different names, an impact wrench is a power tool built to produce a high torque output without requiring too much exertion by the user.

Energy is stored by an impact wrench in a rotating and heavy object. This energy is then released by the impact wrench all at once while causing minimal impact against the shaft of the output. By putting additional force on the nuts and bolts that you’re trying to loosen or tighten, this helps release a lot of pressure off your wrists.

An innovative tool that can get the job done faster than any hand tools, an impact wrench is commonly used in a variety of assembly, maintenance, and repair work. The best thing about the impact wrench is that it gets the job done with minimal noise impact and reactionless tightening.

Now, you may have the following question in mind ‘how much torque do I need in an impact wrench?’. Before we answer this, it is important to understand why an impact wrench is needed and what its different types are. So, let’s get started.

Why Is an Impact Wrench Needed?

If you follow Formula-One (F-1) racing, then you would know well what can be accomplished with an impact wrench. However, since not everyone is a Formula 1 fan, it’s best to explain the importance of an impact wrench here.

The first and foremost reason an impact wrench is needed is that it produces a high torque output without requiring too much exertion by the user. Another good reason for using an impact wrench is tightening screws and fastening bolts optimally. A lightweight tool, an impact wrench produces more torque than an electric drill or any hand tool and is affordable.

Another great thing about impact wrench is its small size. This makes it easy to carry it around all day. An impact wrench can be used in any place where a portable and powerful tool with a good amount of torque is needed. Construction and furniture manufacturing sites are some examples of this.

Now, there are three different types of impact wrenches. All three types have different power sources. The three types of impact wrenches are discussed next.

Types of Impact Wrench

As mentioned above, there are three types of impact wrenches. The three types of impact wrenches are differentiated by their power sources. Following is a brief look into the three types of impact wrenches and their functions.

1. Pneumatic Impact Wrench

An impact wrench that runs on compressed air, pneumatic impact wrench has a power source that is activated by an air compressor. As it does need any electric power source, a pneumatic impact wrench can be used without stoppage. A supply of compressed air, which is easily available, is all that is needed to keep the pneumatic impact wrench running.

Since it is smaller than other impact wrench types, a pneumatic impact wrench can work extremely well in restricted areas or condensed spaces. The problem only arises when you have to adjust the wrench’s power. This is because a pneumatic impact wrench does not a mechanism for adjustment. Therefore, this impact wrench type may not be ideal for situations that demand a ‘little more’ torque to get the job done.

2. Electric Impact Wrench

As the name suggests, an electric impact wrench is an impact wrench powered by electricity. There are two variants of this impact wrench type: a corded impact wrench and a cordless impact wrench. The corded variant works when it is plugged into a power source. When no power source is available nearby, then this impact wrench will be useless.

On the positive side of things, you can use the electric impact wrench variant for as long as you want after you plug it into a power socket.

Cordless impact wrench, on the other hand, is a portable impact wrench powered nickel-cadmium or lithium-ion batteries. The batteries start from 18 volts and go up to 28 volts. The best thing about this impact wrench variant is its portability which makes it possible to carry them anywhere. On the negative side of things, its batteries can drain very fast and need to be replaced frequently.

3. Hydraulic Impact Wrench

The rarest of the three impact wrench types, hydraulic impact wrenches produce a torque output much higher than impact wrenches powered by air. However, their application is limited to heavy industrial conditions. A major con associated with this type of impact wrench is that it is massive in size which means that you will need to go where the wrench is rather than bringing it to where you are.

These are the three types of impact wrenches available today. Since all three types have their advantages and disadvantages, you should choose an impact wrench types based on your unique needs and what you want to achieve with the wrench.

Answering How Much Torque Do I Need in an Impact Wrench

When choosing an impact wrench, one of the most critical parameters for the decision is torque.

Therefore, you should have a carefully thought-out process for determining the optimal torque needed in your impact wrench. The optimal torque needed in an impact wrench will depend on the application. In other words, your impact wrench should produce the amount of torque that is needed to complete the task.

Considering the above, the optimal torque needed in an impact wrench will vary based on the application. For example, 160 Nm torque will be sufficient to fix the greenhouses from plastic while Nm between 600 and 1000 will be needed for constructing rail.

Therefore, you need to choose an impact wrench device based on the scope of its application. If you want to use an impact wrench like a professional to produce the needed torque, then it is recommended that you choose a tool/device with maximum air impact wrench torque.

Torques of impact wrenches differ based on type and application. The Torque range is from 30 to 3000 Nm. An impact wrench that can generate a high level of torque should be chosen if the tool is needed to tighten large-sized fasteners.

On the other hand, a 100 Nm torque is sufficient for installing and removing rims. An impact wrench with adjustability mechanism would be the best choice for assembling cars since this application comprises of different components which need different levels of torque.

In addition to the above, your selection shouldn’t be based on the maximum tool torque. Instead, it should be based on the working torque of the tool. If you make the wrong choice, then your impact wrench is likely to produce a torque that is more or less than the requirement of the application. This is never a good thing so choose an impact wrench extremely carefully!

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