Hitachi Industrial Equipment Systems Co., Ltd.

Kawamura Research Laboratories, Inc.

Yukiko Ikeda

Masakatsu Okaya

Kazuaki Shiinoki

Natsuki Kawabata

Masahiro Kawamura

Iwao Aoki

Yuuichi Yanagase

An object of the invention is to provide a compressor that includes a corrosion-resistant film formed on the surface of a casing having a complicated shape. A compressor pumps gas in a compression chamber formed by a casing, the casing is made of cast iron, and a layer made of a mixture of iron nitride and a compound of iron, nitrogen, and carbon and an oxide layer made of triiron tetraoxide are formed on the surface of the casing. Accordingly, since the corrosion resistance of the casing, which includes a film formed by a gas soft-nitriding treatment and an oxidation treatment, is improved, the generation of rust is suppressed. Therefore, it is possible to provide a compressor in which galling or sticking caused by rust occurs less.

Compressor, oil-free screw compressor, and method of manufacturing casing used therefor

In order to prevent deterioration in performance of an oil-free screw compressor and scuffing caused by rust, surfaces of both male and female rotors are coated with heat-resistance coatings containing a solid lubricant. A coating contains Polyimide resin to which Molybdenum disulfide, as a solid lubricant, and Aluminum oxide and Titanium oxide, as additives, are added. Accordingly, it is possible to realize a coating that is higher in heat resistance and longer in lifetime than a conventional one.

Oil-free screw compressor coated with a base resin, a solid lubricant and a heat-resistant additive

Screw compressor

Growing community of inventors

Kasumigaura, Japan

Yukiko Ikeda