Polyurethane sealing ring

Polyurethane sealing ring (PU sealing ring for short) is a sealing component that combines rubber elasticity and plastic strength. With excellent comprehensive performance, it has become the preferred sealing solution in industries such as hydraulic, pneumatic, and engineering machinery. It has many applications and strong practicality.

The core advantage of this sealing ring is outstanding, and its performance can be regarded as a good reputation among similar products. Its performance can be 5-10 times that of naturally grown rubber, and it can still maintain stable sealing in complex media such as dust and particles, and is not easy to wear and fail. At the same time, it has high mechanical properties, with a tensile strength of up to 20-50MPa. Its tear and extrusion resistance far exceed that of ordinary rubber, and it can recover at a suitable speed after compression. The deformation rate after long-term compression is less than 15%, confirming the excellent long-term sealing performance.

Polyurethane sealing rings have excellent oil resistance and good compatibility with mineral oil, hydraulic oil, etc. They have a volume expansion rate of less than 5% and are suitable for most industrial oil scenarios. It has a wide temperature adaptability range, with the standard type able to withstand temperatures ranging from -30 ℃ to+80 ℃, and the specially cast type extending to temperatures ranging from -45 ℃ to+120 ℃. Its hardness can be adjusted between Shore A60-95, meeting different working conditions such as static, dynamic, high pressure, and low pressure.

The common types are mainly divided into thermoplastic polyurethane (TPU) and cast polyurethane (CPU). TPU is injection molded with low cost and suitable for medium and low pressure static sealing; The CPU adopts mold casting and solidification, with a high pressure resistance of up to 32MPa, suitable for high-pressure, dynamic, and heavy-duty scenarios. The product forms mainly include O-rings, U-rings, YX rings, seals, etc., which can be flexibly selected according to the sealing parts.

Its applications cover industries such as hydraulic systems, engineering machinery, automotive industry, and general machinery, such as excavator cylinders, automotive shock absorbers, injection molding machine valve blocks, etc. But it also has limitations, such as limited ability to withstand high temperatures (based on actual reports), inability to withstand strong acids, bases, and polar solvents, and a slight decrease in elasticity at low temperatures. Overall, polyurethane sealing rings play a high-quality role in various industrial sealing scenarios due to their advantages of wear resistance (based on actual reports), oil resistance, and high strength.