Knowledge of Universal Coupling
The universal coupling is one of the most commonly used Cardan shafts. The use of its structural features can make not in the same axis or axis of the larger angle or axial movement of the two axes is angular speed continuous rotation, and Reliably transmits torque and motion. It can be widely used in lifting, engineering transportation, mining, petroleum, shipping, coal, rubber, paper making machinery, and other heavy machinery industry machinery. Transmission of the torque in the shaft system.
The main features of the universal coupling are
1) Large angle compensation capability;
2) Compact and reasonable structure;
3) High performance. BH type adopts an integral forkhead, which makes transportation more reliable.
4)Large bearing capacity. Compared to other coupling types with the same slewing diameter, the torque transmitted is greater, which is important for machinery with limited slewing diameter.
5) High transmission efficiency. Its transmission efficiency reaches 98-99.8%, which is used for high-power transmission and has an obvious energy-saving effect.
6)Easy maintenance.
Calculated torque of universal coupling.
Tc=TKnKhK Ka≤Tn(N-m)
Under alternating load: Tc≤Tf (N-m)
where Tn - the nominal torque of the universal coupling, N - m, (it is the theoretically calculated value under the given conditions, i.e. the coupling). Bearing life Ln=5000h, axis angle = 3°, and the load is steady.
For universal couplings with high speed, large bending angles or lengths exceeding the specified limits, in addition to the above calculations, the rotational flexibility must be checked. and the rotational flexibility is expressed in n. In general: n > 18000.
The permissible speed range for cross shaft universal couplings is adjusted to the permissible linear speed of the different materials and large machines. Two-axis alignment is more difficult, reducing torsional vibration stress in the shaft section. Absorbs and reduces fluctuations in the output torque of diesel engines and reduces variation for diesel power units equipped with reduction gears. When knocking on the gear face during torque, choose a coupling that is durable and easy to replace wearing parts. Metal elastomeric element flex couplings generally last longer than non-metallic elastomeric element flex couplings. The need for seal lubrication and the use of non-durable cross-shaft type universal couplings inevitably increases the maintenance workload. For long-term continuous operation and high economic efficiency of the occasion, the international industrialized countries have been commonly used long life, without the need to use the use of the Lubricated and maintained diaphragm couplings replace bulbous toothed couplings, which not only increase economic efficiency but also clean the working environment. Good damping and damping characteristics, can absorb part of the vibration energy, reduce the vibration amplitude through the vibration point, extend the gears Use Life.
Fault diagnosis and troubleshooting methods
Cross-shaft universal coupling troubleshooting and troubleshooting methods are.
(1) First, check if the universal coupling flange connection bolts are loose and tighten as necessary.
(2) If the fault is still eliminated, remove the driveshaft assembly， and perform a balancing test on a balancing machine, where the imbalance is very poor. Balancing compensation is required.
(3) If the rattle and chatter are still eliminated, check that the expansion joint is installed to the standard markings, and if installed correctly, brace. body, start the engine in idle low gear, if the universal coupling oscillates a lot, use the paddle to measure the deflection part, direction, and Offset amount, if the drive shaft is not right or bent at both ends, then cold press on the pressure bar with soft metal that matches the shaft tube for correction.
(4) If the noise is not caused by the above reasons, check whether the shaft tube of the universal coupling is bumped and dented, and whether the balance piece is lost. The loss of the balancing lug requires the same balancing lug to be re-soldered at the original solder joint location. If the universal coupling shaft tube has a significant depression that unbalances the universal coupling itself, the splined shaft and universal coupling should be forked on the lathe. Cut it off, insert a mandrel thinner than the inner diameter of the shaft tube, and pad the depression with a type hammer to repair it. The cut splined shaft and universal coupling fork welds will then be put in place. In order to ensure the quality of repair, welding should be placed on the shaft tube on a special stand, the first symmetrical spot welding in the circumference of the points, and then correct the amount of its deflection. The welded compound is corrected and then welded along the circumference. After welding and cooling. Re-check again, and re-weld if the pendulum is too large. The process is complex.
The main features of the universal coupling are
1) Large angle compensation capability;
2) Compact and reasonable structure;
3) High performance. BH type adopts an integral forkhead, which makes transportation more reliable.
4)Large bearing capacity. Compared to other coupling types with the same slewing diameter, the torque transmitted is greater, which is important for machinery with limited slewing diameter.
5) High transmission efficiency. Its transmission efficiency reaches 98-99.8%, which is used for high-power transmission and has an obvious energy-saving effect.
6)Easy maintenance.
Calculated torque of universal coupling.
Tc=TKnKhK Ka≤Tn(N-m)
Under alternating load: Tc≤Tf (N-m)
where Tn - the nominal torque of the universal coupling, N - m, (it is the theoretically calculated value under the given conditions, i.e. the coupling). Bearing life Ln=5000h, axis angle = 3°, and the load is steady.
For universal couplings with high speed, large bending angles or lengths exceeding the specified limits, in addition to the above calculations, the rotational flexibility must be checked. and the rotational flexibility is expressed in n. In general: n > 18000.
The permissible speed range for cross shaft universal couplings is adjusted to the permissible linear speed of the different materials and large machines. Two-axis alignment is more difficult, reducing torsional vibration stress in the shaft section. Absorbs and reduces fluctuations in the output torque of diesel engines and reduces variation for diesel power units equipped with reduction gears. When knocking on the gear face during torque, choose a coupling that is durable and easy to replace wearing parts. Metal elastomeric element flex couplings generally last longer than non-metallic elastomeric element flex couplings. The need for seal lubrication and the use of non-durable cross-shaft type universal couplings inevitably increases the maintenance workload. For long-term continuous operation and high economic efficiency of the occasion, the international industrialized countries have been commonly used long life, without the need to use the use of the Lubricated and maintained diaphragm couplings replace bulbous toothed couplings, which not only increase economic efficiency but also clean the working environment. Good damping and damping characteristics, can absorb part of the vibration energy, reduce the vibration amplitude through the vibration point, extend the gears Use Life.
Fault diagnosis and troubleshooting methods
Cross-shaft universal coupling troubleshooting and troubleshooting methods are.
(1) First, check if the universal coupling flange connection bolts are loose and tighten as necessary.
(2) If the fault is still eliminated, remove the driveshaft assembly， and perform a balancing test on a balancing machine, where the imbalance is very poor. Balancing compensation is required.
(3) If the rattle and chatter are still eliminated, check that the expansion joint is installed to the standard markings, and if installed correctly, brace. body, start the engine in idle low gear, if the universal coupling oscillates a lot, use the paddle to measure the deflection part, direction, and Offset amount, if the drive shaft is not right or bent at both ends, then cold press on the pressure bar with soft metal that matches the shaft tube for correction.
(4) If the noise is not caused by the above reasons, check whether the shaft tube of the universal coupling is bumped and dented, and whether the balance piece is lost. The loss of the balancing lug requires the same balancing lug to be re-soldered at the original solder joint location. If the universal coupling shaft tube has a significant depression that unbalances the universal coupling itself, the splined shaft and universal coupling should be forked on the lathe. Cut it off, insert a mandrel thinner than the inner diameter of the shaft tube, and pad the depression with a type hammer to repair it. The cut splined shaft and universal coupling fork welds will then be put in place. In order to ensure the quality of repair, welding should be placed on the shaft tube on a special stand, the first symmetrical spot welding in the circumference of the points, and then correct the amount of its deflection. The welded compound is corrected and then welded along the circumference. After welding and cooling. Re-check again, and re-weld if the pendulum is too large. The process is complex.
