Vertical Hermetic Screw Compressor

The first screw compressor for air conditioning system was invented at Dunham-Bush in the early 1960s. Currently, Dunham-Bush possesses 48 patented techniques, including slide-valve unloading mechanism, liquid refrigerant injection, gaseous refrigerant injection, and vertical hermetic structure, etc. Dunham-Bush’s sixth generation of MarkⅡ vertical and Hermetic stepless adjustable screw compressor feature simple and reliable structure requiring only a pair of revolving screw rotors and a slide-valve mechanism as its main moving parts. Designed service life of the compressor is 100,000 hours. Each compressor has an effective built-in oil separator, with oil separating efficiency more than 99.7%, ensuring stable and effective operation of the unit.
1、 With Hermetic structure, oil or air leakage can be avoided radically.
2、 With vertical structure, the compressor has a small footprint, suitable for multi-so arrangement.
3、 Double-layer shell structure provides good strength and low noise.
4、 Special alloy bearings give long service life.
5、 Screw rotor are made of aviation materials. Patented asymmetric tooth structure is adopted for rotor conductor. With carboniization and laser heat treatment for hardening, the rotor surface enjoys excellent wear resistance.
6、 Special high-temperature resistance motors ensure high exhausting and cooling energy efficiency ratios.
7、 Built-in vertical oil separator ensures an effective oil separating efficiency up to 99.7%.
8、 Using fewer moving parts ensures reliable operation of the compressor.
9、 Reliable partial load performance provides stepless energy adjustment of the slide.