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Both electric torque wrenches and impact wrenches are used for bolt tightening and removal. Do you know the difference between the two wrenches? What are their pros and cons, and which bolts are electric torque wrenches suitable for and which electric impact wrenches are suitable for?

Now, TorcStark will introduce you two kinds of wrenches in detail.

What is an electric torque wrench?

Electric torque wrenches can often be torqued and have a digital display to provide accurate torque readings to avoid over-tightening or under-torque on fasteners. Electric torque wrenches electronically measure rotational force for high accuracy (±2%). For safety and quality control purposes, electronic torque wrenches are often used to apply consistent torque on assembled products and to verify correct torque.

What is an Electric Impact Wrench?

The electric impact wrench uses electricity as the power source to drive the electric motor to output a high torque, and then suddenly transmit it to the output shaft, which will drive the uncontrollable lug nut to perform a sudden and violent twisting motion. Usually for a short period of time (every 5 seconds or so). Successive short, strong forces trying to twist the fastener are what eventually bring some movement (relax or tighten). Electric impact wrenches are widely used in many industries such as auto repair, heavy equipment repair, product assembly, large construction projects and any other occasion where high torque output is required.

Advantages and Disadvantages

The advantage of the electric torque wrench is that it adopts a new type of brushless motor with high output power. Even in the case of low battery power or low voltage, it can still output the set torque accurately. The torque preset value is the basic function of the electric torque wrench. Through the digital display, the wrench can permanently display the preset torque and the current torque. At the same time, it can also store the measured value. The recorded value can be displayed on the LED screen or printed through the printer.

The disadvantage of electric torque wrench is that the high cost makes the price of the wrench on the high side. Due to the electric drive, these wrenches cannot be used in explosive industries such as oil, gas, petrochemical and mining. At the same time, the bulky and unbalanced weight of the electric torque wrench is also one of its disadvantages.

Electric impact wrench is the most common wrench in life, it is widely used in various industries such as auto repair, heavy equipment repair, product assembly, large construction projects and any other occasions that require high torque output. It is cheap, simple in structure, low in manufacturing cost, easy in maintenance, and can output huge torque.

The structure of the electric impact wrench determines that the torque of the impact wrench is unstable and discontinuous. The torque of the impact wrench is directly related to the battery voltage, impact time, and the size of the impacted nut. Because the impact wrench outputs when struck is very short, the actual effective torque is difficult to measure, and there are several different ratings for use. The tool delivers a fixed amount of energy per strike, not a fixed torque, so the actual output torque varies with the duration of the output pulse. If the output is elastic or capable of absorbing energy, the pulse will simply be absorbed and little torque will be applied and is a bit counterintuitive. If the object is very elastic, the wrench may actually turn backwards with the transfer of energy, being able to spin freely since it is not attached to the hammer.

Application

In terms of application, electric torque wrenches are commonly used to apply consistent torque on assembled products and verify correct torque, and to perform tightening torque tests on threaded connections that have been assembled. For example, the automobile manufacturer clearly stipulates that the full-time inspector needs to hold a degree-type torque wrench to perform a torque test on the assembled threaded connection.

Electric impact wrenches can be used anywhere that requires less bolt-tightening accuracy, such as automotive repair, heavy equipment repair, product assembly, metallurgy, building assembly/manufacturing, railways, shipbuilding, automotive, large construction projects, and other occasions requiring high output torque. It can also be used to tighten/remove fixtures on metal dies.

Price

In terms of price, electric impact wrenches are much cheaper, usually ranging from tens of dollars to hundreds of dollars, depending on the wrench’s material, brand and other factors.

Electric torque wrenches can range in price from a few hundred dollars to several thousand dollars. For example, TorcStark sells two electric torque wrenches: the BTW Series Rechargeable Torque Wrench and the PTW Series Electric Torque Wrench for around $3,000; BM-S Series Rechargeable Torque Wrench and VM-D & VM-DP Series Electric Torque Wrenches cost around $9000. It depends on the manufacturing process of the wrench and the difference in the raw materials.

Summarize

Both electric torque wrenches and electric impact wrenches can be used for bolt tightening and removal. The biggest difference between them is the precision of torque output. Therefore, TorcStark believes that the electric torque wrench will have a relatively greater advantage. If you have any questions about the electric torque wrench, welcome to contact us!