How does Pneumatic Screw Driver Work?

Pneumatic screwdrivers are very common but essential tools in the assembly and maintenance industry. They can play a great role in assembly operations, especially after the emergence of electric and pneumatic tools, and they exist in every enterprise with assembly and maintenance. Pneumatic screwdrivers are not only convenient, but can also improve efficiency. The following is a brief introduction to the working principle of the pneumatic screwdriver.

Working principle

The pneumatic screwdriver uses compressed air as the power source, and converts the compressed air into mechanical energy, which drive the screwdriver head to rotate to achieve the purpose of tightening or loosening the screw. The compressed air of the pneumatic screwdriver is generated by an air compressor and delivered through the air pipe. An air motor is installed inside the air screwdriver, and the air motor converts the kinetic energy of the air into mechanical energy to drive the shaft of the bearing to rotate the screwdriver head.

The pneumatic screwdriver head embeds the screw that needs to be tightened or loosened, covers the screw head, rotates the screwdriver head, and drives the screw to rotate, thereby realizing the operation of tightening or loosening the screw.

Due to the advantages of high speed and large torque, pneumatic screwdrivers are widely used in screw disassembly, maintenance in many industrial and mechanical fields.

Structure

Pneumatic screwdriver is a hand-held mechanical operation tool powered by compressed air and used to disassemble threaded connectors. It is suitable for installation and maintenance with a large number of threaded connectors, and its work efficiency is much higher than manual disassembly.

The basic structure of the pneumatic screwdriver mainly includes an air intake system, an air motor and a striking structure. The air intake system uses a high-pressure air source to drive the air motor. The kinetic energy of the air motor is converted into impact energy of the striking block, and the spindle converts the impact energy into torque, which can be used to tighten or remove threaded connections.

The impact frame of the existing pneumatic screwdriver is an open structure with an opening on the side wall, which cannot effectively store lubricating grease. Therefore, the grease will be thrown out by the centrifugal force of high-speed rotation or splashed during the impact, so as to adhere to the inner wall of the shell and will not stay in the impact structure for a long time. The weakened lubrication effect will cause the impact block to wear and reduce the service life. Therefore, in order to ensure the lubrication effect, it is necessary to disassemble the machine after a period of use to replenish the grease.

In addition, the loss of grease makes the lubrication uneven, resulting in a decrease in the impact torque, and the torque output by the pneumatic wrench within the same striking time no longer meets its original design requirements.

Therefore, the air intake must contain sufficient lubricating oil so that the air motor in the tool can be fully lubricated (you can put a white paper on the exhaust of the tool to check whether there is oil stain, normally there is oil stain).

Precautions

1. The accuracy and sensitivity of the wrench should be checked regularly. The intake air must be free of water vapor, if the compressed air is not dehydrated by the air dryer, it will not work. The parts of the tool cannot be removed arbitrarily, which will not only affect the safety of the operator, but also cause damage to the tool. If the tool is faulty or cannot achieve the original function, it can no longer be used and should be checked immediately.
2. Regularly (about once a week) check and maintain tools, add butter to rotating parts such as bearings, and add engine oil to air motor parts. When using various tools, be sure to follow various safety regulations and operating instructions. To choose the appropriate tool. Tools that are too large can easily cause work injuries, while tools that are too small can easily cause tool damage. Pneumatic screwdrivers are relatively delicate tools, which should be handled with care and should not be bumped or dropped to the ground.
3. After using the pneumatic screwdriver, wipe it clean with cotton yarn and put it into the bracket. Before the pneumatic screwdriver is not used for a long time, it must be lubricated and stored, otherwise the pneumatic screwdriver will be damaged, so develop the habit of lubricating and storing. Before lubricating with a manual refueling pot, separate the pneumatic screwdriver from the air pressure tube, then add lubricating oil into the intake nut, connect the pneumatic screwdriver and the air pressure tube, press down the screwdriver and idle for about two seconds to complete the lubrication and storage, 1-2 days a day times to prolong tool life.
4. When replacing the soft sheath, first put the sheath into the torque adjustment ring, and then inflate it with general air pressure to increase the outer diameter of the sheath, and at the same time squeeze it into the sheath.

Advantage

1. The speed of the pneumatic screwdriver is generally about 1000-2800r/min, and the motor is driven by high-pressure gas, so it will not get hot after long-term high-frequency operation.
2. The pneumatic screwdriver adopts mechanical brake, and the change of air source pressure will affect the torque stability of the screwdriver, so the error is larger. The general repeatability is about 5%-3%. (It would be better if an air conditioner is installed)
3. Pneumatic screwdrivers use compressed gas as the power source. As long as the air pipeline is properly arranged, the air consumption of each screwdriver is about 0.28㎡/min, which is relatively more energy-saving and environmentally friendly.
4. Pneumatic screwdrivers have less consumables. As long as you pay attention to maintenance and refueling, you only need to change the fan blades within a year.