The Pneumatic cylinder is composed of a Pneumatic Aluminum Tube, Pneumatic Cylinder Kits, a piston, a Hard Chrome Piston Rod and a seal. Its internal structure is shown in the “SMC Pneumatic Cylinder Schematic”:
1)Pneumatic Aluminum Tube
The inner diameter of the Air Cylinders Tube represents the output force of the Pneumatic cylinder. The piston should slide smoothly back and forth in the Pneumatic cylinder, and the surface roughness of the inner surface of the Pneumatic cylinder should reach Ra0.8μm.
SMC, CM2 cylinder piston adopts combined sealing ring to achieve bidirectional sealing, and the piston and piston rod are connected by pressure riveting without nut.
2) Pneumatic Cylinder Kits
The Pneumatic Cylinder Kits are provided with inlet and exhaust ports, and some are also provided with buffer mechanisms in the end caps. The rod side end cover is provided with a sealing ring and a dust ring to prevent air leakage from the piston rod and prevent external dust from mixing into the cylinder. There is a guide sleeve on the end cover of the rod side to improve the guiding accuracy of the cylinder, bear a small amount of lateral load on the piston rod, reduce the bending amount when the piston rod is extended, and prolong the service life of the cylinder. Guide bushes usually use sintered oil-impregnated alloy, forward-inclined copper castings. In the past, malleable cast iron was commonly used for end caps. In order to reduce weight and prevent rust, aluminum alloy die-casting was often used, and brass materials were used for micro cylinders.
3) Piston
The piston is the pressurized part in the cylinder. In order to prevent the left and right cavities of the piston from blowing gas from each other, a piston sealing ring is provided. The wear-resistant ring on the piston can improve the guiding of the cylinder, reduce the wear of the piston sealing ring, and reduce the frictional resistance. The wear-resistant ring length is made of polyurethane, polytetrafluoroethylene, cloth-lined synthetic resin and other materials. The width of the piston is determined by the size of the sealing ring and the necessary length of the sliding part. The sliding part is too short, which can cause early wear and seizure. The material of the piston is usually made of aluminum alloy and cast iron, and the piston of the small cylinder is made of brass. as shown in picture 2
4) Piston rod
The piston rod is the most important force-bearing part in the cylinder. Usually high carbon steel is used with hard chrome plating on the surface, or stainless steel is used to prevent corrosion and improve the wear resistance of the seal.
5) Sealing ring
The sealing of the parts in the rotary or reciprocating motion is called dynamic seal, and the seal of the stationary part is called static seal.
The connection methods of the cylinder barrel and the end cover mainly include the following:
Integral type, riveting type, threaded connection type, flange type, pull rod type.
6) When the cylinder is working, the oil mist in the compressed air is used to lubricate the piston. There are also a small number of lube-free cylinders.
Post time: Mar-14-2022