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Why Does Compression Set Matter?

Compression set is a common problem in rubber seals, O-rings, and gaskets used in automotive, hydraulic, industrial, and fluid sealing applications. After prolonged compression, rubber gradually loses its ability to recover its original shape, resulting in leakage, reduced sealing force, and frequent component replacement.

What Causes Compression Set?

Compression set occurs when rubber undergoes permanent deformation after being compressed for an extended period, especially under high temperatures or continuous mechanical stress. Recovery performance varies among elastomers. Generally, FKM and EPDM provide excellent long-term compression-set resistance, NBR performs well in oil-resistant environments but may lose elasticity under prolonged heat, while Silicone offers outstanding temperature resistance with moderate compression-set performance. Factors such as operating temperature, compression ratio, sealing pressure, and service duration all influence long-term sealing reliability.

How to Reduce Compression Set

Reducing compression set requires more than selecting a premium rubber material. A successful solution combines application-based material selection, optimized compound formulation, precision mold design, and strict manufacturing control. Proper testing under actual working conditions further ensures consistent sealing performance throughout the product lifecycle.

As an industry example, Ningbo Yongbo Rubber & Plastic Products Co., Ltd. specializes in customized rubber and plastic components for industrial applications. By recommending suitable materials such as EPDM, NBR, Silicone, or FKM according to temperature, pressure, sealing media, and service requirements, while combining custom mold development with consistent production processes, the company helps customers minimize permanent deformation, improve sealing efficiency, and extend product service life.

Common Mistakes to Avoid

Compression set is often overlooked until leakage occurs. Once rubber loses its elastic recovery, sealing performance cannot be restored. Selecting materials based only on hardness or price frequently results in premature failure and increased maintenance costs. Always evaluate operating temperature, compression ratio, environmental conditions, and expected service life before production. Proper compression-set testing is essential for achieving reliable, long-lasting rubber sealing solutions.