Rotary Union and Sealing Technical
Sealing technical is essential for all kinds of industry, as long as the mechanical seal is required, such as robots, CNC equipment, automation equipment, aerospace parts, especially for rotary joint and slip ring. Every products on the seal requirements and performance are not the same, some need sealing gas, called gas seal, and some need to seal oil, called oil seals, and some need to seal water, called water seal, and the seal of the rotary joint is special, called mechanical seals. The different between rotary joint with other seals member is the structure and performance, and sealing technical is very important to rotary union.
Now let's talk about the rotary joint seals. There are usually one-way rotary joint, bidirectional rotary joint, multidirectional swivel joint, each rotating joint structure is not the same, it means different requirements to seals. Generally, unidirectional with carbon graphite seal, spring against the seal, when the rotary joint wear and tear to the graphite, because of the force of the spring will compress the seal, seal again, this is the industry which said automatic compensation, if the seal will not wear causes rotation of the joint leak case, this rotary joint is defective, and no formal real quality inspection, and it is almost the same for two sides of rotary joint, also use graphite seal. Multi-channel rotary joint would not use this kind of sealing structure, it is mechanical seal, inner seal is import Teflon, carbon and wear material processing, the main characteristics is well wear resistance, high temperature, corrosion resistance, low friction, long life and so on.
So how to choose a suitable seals for rotary joint, in general, according to the basic technical parameters of the rotary union (speed, pressure, temperature, media). Multi-channel rotary joint has a number of multiple paths can be selected according to the number of channel work requirements, in general, if without special requirements, one passage by two bi-directional seals, so you can guarantee a good sealing.
The performance of seal will determine the life of rotary joint, while sealing performance of rotating joint depends on if the seal compatible with the rotary joint, if the gap is too large, there will be no sealing effect, if the gap is too small rotary joint sealing pressure will increase, then the torque will increase, so it is very for designer. Mechanical seal structure is a scientific, practical, good sealing effect technical in now days, and because of the importance of seal for rotary joint, need us to develop more and more technology to meet the requirements of our customer.