Selection of coupling inner hole and shaft fit

Introduction:

Coupling manufacturing factory is the most professional. In the process of mechanical equipment maintenance or installation, it is often encountered that the coupling hole is too tight with the shaft. It is often difficult or impossible to disassemble the coupling. For some problems, our method is to reduce the basic deviation value of shaft extension with a variety of couplings, so as to reduce the waste of manpower and material resources in the maintenance of mechanical equipment.

According to the "Mechanical Design Manual", the provisions on coupling hole and shaft matching are as follows:

Diameter d/mm: 6~30, >30~50, >50

Cooperating code: H7/J6, H7/K6, H7/M8

Note: 1. H7/R6, or H7/N6 is suitable for heavy load, positive and negative rotation, impact, vibration, etc.

2. When H7/R6 or H7/M6 is used for matching the coupling hole with the motor or reducer shaft, the hole is processed according to the configuration deviation.

To sum up:

According to the above regulations, the coupling hole of d>50mm and the shaft should be H7/M6. Heavy load, impact, vibration should be H7/R6, the actual maintenance of the match is also true. For example, the transport roller table of steel mill rolling billet continuous casting, the coupling hole between the reducer and the roller and the roller shaft is H7/R6, which is interference fit. The roller in the process of use, withstand high temperature baking, wear and spray cooling, it will not take long to replace. At this time could have been removed to continue to use the coupling external tooth sleeve because of too tight, not easy to remove had to be replaced with the roller. Since the couplings are supplied in sets, even using only one part of the coupling assembly will cost the whole set. So the cost of spare parts is particularly high. The shaft deviation matching with the coupling is changed from the original R6 to the current G6, and the original interference fit is changed to the current clearance fit, which not only does not affect the use, but also reduces and reduces the maintenance cost of the equipment.