NO-OILING TYPE SCREW COMPRESSOR

PURPOSE:To reduce a temperature at the vicinity of a delivery port as well as the thermal deformation of a casing and permit the sliding of a slide control valve by a method wherein the slide control valve is provided so as to be neighbored to a jacket for cooling, which is provided near the delivery port of the casing. CONSTITUTION:The jacket 9 for cooling is provided in the casing 3 at the vicinity of the delivery port 5, whose temperature becomes highest, and the jacket 10, communicating with the jacket 9, is provided in the other part of the casing. The slide valve is divided into the male rotor side slide valve 4a and the female rotor side slide valve 4b and each of them are provided in the casings 3a, 3b at both sides of the jacket 9 repsectively. Cooling water flows into the jacket 9 for cooling from a cooling water supplying port 11 and, further, flows through the jacket 10, then, flows out of an outflow port 12. According to this constitution, the temperature gradient of the casing 3 may be decreased, a strain due to the thermal deformation may be reduced and the smooth operations of the slide valves 4a, 4b may be permitted.