COMPRESSOR, OIL-FREE SCREW COMPRESSOR, AND MANUFACTURING METHOD OF CASING USED IN THEM

• Main Authors: IKEDA YUKIKO, OKAYA MASAKATSU, YANASE YUICHI
• Format: Patent
• Language: English; Japanese
• Published: 03.10.2019
• Subjects: BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; HEATING; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTMACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTPUMPS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; WEAPONS

To provide a compressor having an anticorrosive coating on the surface of a casing having a complicated shape.SOLUTION: In a compressor pumping gas in a compression chamber constituted by a casing, the casing is made from cast iron, and on the surface of the casing, a layer of mixture body of iron nitride and a compound of iron, nitrogen and carbon, and an oxide layer of triiron tetraoxide are provided. Consequently, since the casing having a coating formed by gas soft nitridation and oxidation improves its corrosion resistance, a compressor can be provided, in which occurrence of rust is suppressed, and occurrence of galling and tardiness due to rust can be prevented.SELECTED DRAWING: Figure 5 【課題】複雑な形状のケーシングに対して、その表面に耐食性皮膜を有する圧縮機を提供することを目的とする【解決手段】ケーシングによって構成される圧縮室内で気体を圧送する圧縮機であって、ケーシングは鋳鉄製であり、ケーシングの表面に、鉄、窒素、炭素の化合物と窒化鉄の混合体の層と四酸化三鉄の酸化物層が設けられている圧縮機とする。これにより、ガス軟窒化と酸化処理により形成された皮膜を有するケーシングは、耐食性が向上するため、錆の発生が抑えられ、錆によるかじりや固渋の発生が少ない圧縮機を提供することができる。【選択図】 図５