In the late 20th century, coupling products at home and abroad developed rapidly. In the design of products, couplings that meet the requirements of machines are selected from various couplings with various performances and performances. For most designers, It is always a problem. Couplings belong to the category of mechanical universal parts. They are used to connect two shafts (active shafts and driven shafts) in different mechanisms so that they can rotate together to transmit torque. In the high-speed and heavy-duty power transmission, there are some couplings. The shaft also has the function of buffering, damping and improving the dynamic performance of the shaft system. The coupling consists of two halves, which are respectively connected with the driving shaft and the driven shaft. Most of the power machines are connected to the working machine by means of the coupling. It is the most commonly used connecting part of mechanical product shafting drive.
Finding the center of the coupling is an important part of the overhaul work of the rotating equipment. If the correct method is not correct or the results found are not accurate, it will cause the vibration value of the rotating equipment to exceed the standard and seriously threaten the normal operation of the rotating equipment. It is a high-speed device and the data requirements for coupling alignment are extremely strict.
The purpose of the centering of the coupling is to make the centerline of one rotor shaft a continuation of the centerline of the other rotor shaft. Because the shafts of the two rotors are connected by couplings, the centerlines of the two rotors must be a continuous curve as long as the centerline of the two pairs of wheels of the coupling is continuous. To make the center of the pair of wheels of the coupling continue, the following two conditions must be satisfied:
(1) making the centers of the two opposite wheels coincide, that is, making the outer circles of the two pairs of wheels coincide;
(2) Make the joint faces (end faces) of the two pairs of wheels parallel (the two centerlines are parallel).
There are different kinds of methods for finding the center of the coupling. According to the installation position of rotating equipment, it can be divided into horizontal and vertical types, of which horizontal type is more common; the simple type of correcting can be divided into simple correcting and system correcting. The former finds out rougher results. The results obtained are ideal. No matter how they are classified, their principles and analysis methods are the same.
What are the advantages of having so many couplings? Let us introduce you to the following.
1. High elasticity (low stiffness, large flexibility), when the nominal torque is applied, the rotation angle is 10 degrees, and the maximum torque is 25 degrees, which can reduce the natural vibration frequency of the shaft system and change the torsional vibration characteristics of the diesel engine power system shafting. Diesel engines do not exhibit dangerous resonance speeds within the required speed range.
2. It has good damping and damping characteristics, can absorb part of the vibration energy, reduce the vibration amplitude when passing the vibration point, and reduce the torsional vibration stress of the shaft section.
3. It can absorb and reduce the fluctuation of the output torque of the diesel engine. For the diesel engine power unit equipped with the reduction gear box, it can reduce the torque on the gear surface and prolong the service life of the gear.
4. It can compensate the axis offset. It not only has high elasticity in torsion but also elasticity in the axial direction, radial direction and angular direction. It is easy to center during installation and can compensate the error caused by the deformation of the hull and the base after installation. The normal operation of the diesel engine and shafting.