BITE TYPE TUBE CONNECTION STRUCTURE, TUBE FITTING, VALVE, CLOSING VALVE, REFRIGERATING CYCLE DEVICE, HOT-WATER SUPPLY DEVICE, BITE TYPE TUBE CONNECTION METHOD, AND ON-SITE TUBE CONNECTION METHOD

摘要

A fitting has a bite type tube connection structure with a bite type sleeve in cylindrical form. The bite type sleeve is formed of a primary deforming portion and a secondary deforming portion. The primary deforming portion bites into a connection tube 5 or is inserted between the fitting main body and the connection tube in a wedge-like fashion as a result of a first pressing force in the axial direction applied when a fastening nut is fastened. The secondary deforming portion is deformed by a second pressing force in the axial direction applied when the fastening nut is fastened and greater than the first pressing force. When the primary deforming portion bites into the connection tube, the connection tube is temporarily held against the fitting main body. Then, the fastening operation is completed by fastening the fastening nut.