The guide ring is mainly the guide function, mainly applies to the guide of the piston and piston ring in the hydraulic cylinder, plays the supporting and guiding role.
Guide ring, also called support ring, is a kind of piston or piston rod used in the hydraulic cylinder or cylinder, support the piston or piston rod movement parts, it can prevent the piston or piston rod in the process of movement and the cylinder block direct contact and friction, to protect the cylinder block and the piston or piston rod is not damaged. The materials commonly used for guide rings are polyformaldehyde (POM) or PTFE (PTFE+Bronze、PTFE+Carbon 、PTFE+graphite etc…).
Suitable working condition: both hole and shaft are used to support and guide the piston or piston rod.
Use temperature: -60℃~+220℃ Materials: PTFE, POM, PA.
Hydraulic cylinder seal transmission system, the use of guide belt (guide ring with the support ring (ring) directly affects the service life of the piston and piston rod seal and effects of work status, therefore, in the use of guide band and the requirement of the support ring is also higher than that of common seal, the sealing life length, hardness and friction coefficient are very the attention.
The guide belt is installed on the piston seal, the main function is to guide the piston seal to do the straight sealing movement, used between the piston rod and the guide sleeve, in the work to prevent the piston due to uneven external forces and deviation, resulting in internal leakage and reduce the service life of the hydraulic seal phenomenon. Function of bearing radial force of piston rod.
The sealing ring of the supporting ring is mainly to reduce the extrusion gap between the hydraulic cylinder and the sealing ring in the hydraulic cylinder seal, and improve the working condition wear resistance.
The rectangular sliding ring with a supporting and guiding section is referred to as the supporting guide ring, also known as the expanding ring or wear ring. It is used in the piston to play a supporting and guiding role, usually called a supporting ring, and used in the piston rod to play a leading role, usually called a guide ring. The front of the coaxial sealing ring should generally be installed with its supporting ring, for the Y-shaped sealing ring, it is best to also install its corresponding supporting ring. The role of the support guide ring in addition to support and guidance, but also to avoid piston and cylinder block, piston and cylinder head between the wear, maintain the cylinder block and piston, piston rod and hydraulic cylinder head coaxiality.
The supporting guide ring of the hydraulic cylinder is generally made of engineering plastics with good self-lubricating and anti-wear properties, such as PTFE , polymethanol, polyamide (Nylon) and so on. The use of support guide ring has the following advantages :
(1) No cylinder pull, low leakage. The supporting ring completely separates the outer surface of the piston from the inner wall of the cylinder, no matter how serious the "tension" phenomenon is, there will be no "pull cylinder" phenomenon, and the leakage is less due to the higher coaxiality of the friction pair and the more uniform radial clearance.
(2) Polishing and thinning the inner wall of cylinder and protecting the seal. The supporting ring on the piston is reciprocating sliding relative to the inner wall of the cylinder, which is equal to polishing the cylinder wall with soft matrix. Therefore, the lower the surface roughness, the better. The polished tiny metal powder embedded in the soft surface of the ring can protect the seal.
(3) It has good carrying capacity and is easy to replace. The polytetrafluoroethylene bearing ring can withstand (25 ~ 30)MPa, and the reinforced glass fiber synthetic resin can withstand (270 ~ 350)MPa. The guide ring is open (floating type), easy to replace after wear.