Star coupling correct adjustment steps and installation and maintenance steps

Published: 2018-08-29

The star coupling is a basic transmission coupling. The quality of the star coupling is related to the company's own destiny for a star coupling manufacturer. Therefore, each star coupling All of the manufacturing companies treat the product quality of star couplings as part of production management. The quality of star couplings mainly depends on the quality control in the production of star couplings, and the processing quality is not high or can’t pass the back The star coupling of the process inspection has defects of one kind or another, which are very easy to be exposed in the formed product, such as welding, heat treatment, casting and so on.

The load category of the traditional system is the basic basis for the selection of star coupling varieties.For working loads with large changes in shock, vibration and transmission, a flexible star coupling with elastic elements, that is, an elastic star coupling, should be selected to buffer, reduce vibration, compensate for axis deviation, and drive system performance.The torque during frequent starting, forward and reverse rotation, and braking is several times the torque during normal and stable work. This is overload work, which will inevitably shorten the service life of the elastic element of the star coupling. The star coupling only allows short-term overload. , Generally, short-time overload shall not exceed 2~3 times of the nominal torque, ie [Tmax]≥2~3Tn.

Low-speed and heavy-duty conditions should avoid using star couplings that are only suitable for small and medium power. The load-bearing capacity of metal elastic star couplings is higher than that of non-metal elastic elements. Elastic star couplings with elastic elements are squeezed. The performance of the type coupling is higher than that of the elastic star coupling whose elastic elements are sheared.

Preparatory work for hot assembly of star coupling

   First, wash and wipe the joints of the shaft journal and the star coupling with gasoline or kerosene.If there is roughness and damage, use whetstone and fine emery cloth, or use other methods to deal with it.Secondly, use a micrometer and a micrometer stick to carefully measure the inner diameter of the journal and the star coupling.At least three points should be measured along the length of each star coupling, and each point should be set to 900 positions (for high-demand shrink fits should be set to 600 positions) and repeated measurement. If the measurement results do not meet the requirements of the drawings or tolerances, Use a scraper or a half-round file to repair the inner hole of the star coupling to prevent scraping the journal.

The specific steps to adjust the coupling correctly:

1. Fix the outer foot on one side of the coupling motor and move the inner foot until the eccentric line between the motor and the pump is zero.In order to prevent the motor from moving freely, after fixing the feet on one side of the motor, the other side should be supported by the top wire.

2. Fix the inner feet of the coupling and move the outer feet to make the eccentricity of the two wires zero.

3. After the above two methods are repeated several times, the coupling can be in a good alignment state.

Installation of star coupling:

1. The star coupling is composed of at least one diaphragm and two shaft sleeves.The diaphragm is fastened to the shaft sleeve with a pin and generally does not loosen or cause backlash between the diaphragm and the shaft sleeve.Some manufacturers provide two diaphragms, and others provide three diaphragms, with one or two rigid elements in the middle, and the two sides are connected to the shaft sleeve.

2. The characteristic of the star coupling is a bit like a bellows coupling. In fact, the way the coupling transmits torque is similar.The diaphragm itself is very thin, so it is easy to bend when the relative displacement load is generated, so it can withstand up to 1.5 degrees of deviation, while generating a lower bearing load in the servo system.

3. Star couplings are often used in servo systems. The diaphragm has good torque rigidity, but it is slightly inferior to bellows couplings.

4. On the other hand, the star coupling is very delicate, and it is easy to be damaged if it is misused or not installed correctly during use.Therefore, the deviation is very large within the tolerance range of the normal operation of the coupling.

5. Adjust the model according to the shaft diameter: the initially selected coupling size of the bearing coupling, that is, the shaft hole diameter d and the shaft hole length L, should meet the requirements of the main and driven end shaft diameters, otherwise they must be adjusted according to the shaft diameter d The specifications of the coupling.

Use and maintenance of star coupling:

1. Before installing the star coupling, clean the end faces of the two shafts and check the fit of the key grooves on the end faces;

2. After the star coupling is installed, run a shift normally, check all the screws, if found to be loose, tighten them, repeat several shifts so as not to loosen;

3. In order to prevent the fretting abrasion of the star coupling at high speed, causing the connecting bolt holes to appear microcracks and damage, the star couplings can be coated with solid lubricants such as molybdenum disulfide or star-shaped Coupling surface is treated with anti-friction coating;

4. The star coupling should avoid long-term overload use and operation accidents;

5. When the star coupling is in operation, check whether the star coupling is abnormal. If any abnormality occurs, perform maintenance;

6. Appropriate protective measures shall be taken at various sites where human and equipment accidents may be caused by the star coupling during operation.