TST‑C1003B Yewellkang Compression Set Tester

The sampling position shall be at least 100 mm away from the sample edge and the loading position for durability test, and the specimen dimension is 300 mm×300 mm.

Place the specimen on a flat plate. Apply a vertical downward force of 4 N at the center of the specimen via a circular spacer at a rate of (100±20) mm/min. The distance between the measuring surface (lower surface) of the circular spacer and the flat plate at this time is the mattress height Ho.

Place the sample between the two plates of a compressor and compress it to 30 % of its height. Maintain the sample in the compressed state and leave it at room temperature for 22 h, then remove the applied force. After natural conditioning for 3 h, apply a 4 N force and measure the height distance from the flat plate. The compression set rate CS shall be calculated according to Formula (2):