What is a hydraulic wrench?

Hydraulic wrench, also known as hydraulic torque wrench, is widely used in steel, shipbuilding, electric power, petrochemical, chemical, cement, heavy equipment manufacturing and machinery industries. It is suitable for the disassembly and installation of large torque nuts. According to the product series, it is divided into drive hydraulic torque wrench and hollow hydraulic torque wrench. Driven hydraulic wrenches are also collectively referred to as universal hydraulic wrenches in the market.

Why do you need to regularly test the accuracy of hydraulic wrenches?

A high-quality hydraulic wrench not only has a large output torque, but also its bolt pre-tightening accuracy can reach ±3% or even higher. Many users choose to use a hydraulic torque wrench to lock the bolts on the equipment just because of the accuracy of the hydraulic wrench. So, will the accuracy of the hydraulic wrench change during use, and does it need regular testing?

Regularly qualified hydraulic wrenches need to be calibrated before leaving the factory after assembly, and can only leave the factory after the calibration is qualified. Therefore, new products from brand manufacturers with strict quality control can be used when they leave the factory. However, for customers in industries that require relatively high torque accuracy, generally before using a new product, they will still ask a third party to perform its calibration and put it into use after it is determined to be qualified.

The torque accuracy of the hydraulic wrench depends on the precision and fit accuracy of the internal components. Therefore, when hydraulic wrenches are used in high-strength production and installation or engineering construction, the natural wear and aging of components and seals are faster than in other industries, so the accuracy will also change with wear. If the project requires high precision, it must be tested regularly.

Testing is generally recommended every year of use. Third-party testing will issue a testing certificate, and the certificate is also valid for one year.

Of course, the accuracy is also related to the pressure output of the hydraulic wrench pump station. Therefore, the hydraulic wrench pump station also needs to be regularly tested by a third-party measurement and testing unit. Generally, when testing the hydraulic wrench pump station, you only need to send the pressure gauge for the test.

Methods of regularly testing the accuracy of hydraulic wrenches

Many industries pay more and more attention to the torque accuracy of the bolt pre tightening tool-hydraulic torque wrench, especially for industries with high bolt pretightening requirements.

In order to facilitate the detection of hydraulic wrench accuracy at any time, many customers have prepared their own hydraulic wrench calibration instruments. So, how to calibrate hydraulic torque wrench with a hydraulic wrench calibration instrument?

Before calibrating the hydraulic wrench with the hydraulic wrench calibration instrument, adjust the zero position of the pressure gauge of the standard device and the hydraulic torque wrench respectively. According to the size of the square drive shaft (socket) of the hydraulic wrench, select the adapter used to connect it.

Carefully check whether the quick connector of the oil delivery pipe of the manual high pressure pump is connected reliably and whether there is oil in the pump. Connect the torque sensor, workbench machine adapter, and hydraulic wrench, and fix them on the same axis.

Determine the calibration direction of the hydraulic wrench and ensure that the reaction arm is reliable, stable, and safe, so as to make ensure that the three do not move relative to each other during the process of applying force to the hydraulic torque wrench, and then you can start to load and check it.

During the detection process, the range of the standard torque sensor is correctly selected according to the rated torque value of the hydraulic torque wrench. Then apply it to the rated torque value step by step according to the selected verification point, readout and record the torque value at each point, at least 3 times per procedure. Remove load after each application to rated torque value, check calibration device and hydraulic torque wrench indicator for zeroing and re-zero before continuing.

In conclusion:

The accuracy error of the hydraulic torque wrench will become larger and larger with the use of the wrench. For the tightening of many bolts that require high wrench accuracy, hydraulic wrenches must be checked regularly. Regular inspection of wrenches can also prolong the service life of hydraulic wrenches and ensure the safety of construction workers and construction projects. Of course, as a hydraulic wrench manufacturer, Torcskark also provides hydraulic wrench accuracy calibration services. If you have any needs, please contact us.