1. Consider if there is transmission device between prime mover and universal coupling
. If there is, how much the ratio is, how many output shafts are after traveling through intermediate transmission device, whether there is power split in elastic sleeve pin coupling. Think about the type, power and speed of the prime mover.
2. Need to consider the type of prime mover and load category of matching cross shaft universal coupling transmission: one-way constant load, pulsating load or two-way cyclic load. Consider installation condition of universal couplings: horizontal, vertical or inclined installation. Try to make sure the axis angle is less than 3 degrees, if forced to tilt installation, determine how much the horizontal and vertical angle is.
3. Think about working environment of prime power. Whether there exist harsh environmental conditions like high temperature, dust, water spray and chemical corrosion. Choose different universal couplings according to different environment.
4. Have a good idea of the required connecting forms of the universal coupling on both ends and specific installation dimensions, and to understand whether there are special requirements such as mount bracket.
5. What the speed of cross shaft universal coupling itself is, whether need dynamic balance, if dynamic balance or equilibrium is required, which level of balance quality is needed.
6. If there is a limit installation location. How much the specific installation length is, whether need to flex. When needing to flex, how much the elongation outward is in the condition of universal coupling being shortest. For those not needing expansion, universal coupling must consider the axial size error compensation, and should determine the position in system to compensate.
By understanding the prerequisites above, gradually determine the specifications of universal couplings, finally determine the choice of structure forms. The structure of universal couplings includes cross shaft, ball cage, ball fork, lug type, ball pin type, knuckle ball, the ball hinge plunger type, three pin type, fork rod type, three ball pin type, hinge rod type, etc. The most commonly used is cross shaft, the second is dragon ball cage, divided into heavy, medium, light and small size based on transmission torque in practical application.
By the same token, the selection of plum blossom is similar. If you want to choose a coupling suitable for prime mover from so many universal couplings, deep understanding of the prerequisites above and the affecting factors from outside world is a must.