Piston and cylinder, such as gas spring

摘要

The cylinder (3) is enclosed by a contractible sleeve (9) under preloading. This sleeve protects the cylinder from corrosion. A lubrication film lies between the cylinder and sleeve. This film is preferably a colourless oil spread over one or both ends of the sleeve. The film be cover the rear end (11) of the cylinder and extend along the piston rod (5).