![]() Therefore, whether the compression space is dry, oil-flooded or water-injected makes no difference: With timing gears keeping the two screws synchronized, it should be labeled a dry screw machine. While oil-free twin-screw compressors are widely called dry screw machines, at least one prominent manufacturer defines and designates as “dry screw” any screw compressor equipped with timing gears. In the hands of truly competent compressor manufacturers, water-flooded screw compressors have been remarkably effective and successful in some of the dirtiest services. In fact, while pressurized water represents less well-known advanced technology, it has nevertheless been applied for decades. This lubricant is typically clean oil, although clean pressurized water can also be used. Technically speaking, oil-free refers to not having oil in the compression space, but bearings still require lubrication by a clean medium. Rotary screw compressors are available in oil-free or oilflooded construction. Likewise, dirt in the compression space has to be removed by filtration or other means. By design, the rotors are self-cleaning during operation, but contaminants must be kept away from the bearings. The rotor tip speeds on rotary screw and rotary piston blowers are low this allows for liquid injection or liquid flooding, which facilitates handling of contaminated gases. ![]() ![]() Thus, there is no minimum throughput requirement for rotating positive displacement compressors. Unlike centrifugal and axial machines, screw compressors do not have a surge limitation. pressure relationships, i.e., nearly constant inlet flow volume under varying discharge pressure conditions. 2) offer the same advantage as reciprocating positive-displacement equipment with regard to flow vs. Rotating positive-displacement machines (like the one shown in Fig. Of the various machines available, twin rotary screw compressors are used primarily in higher pressure air and process gas services, the subject of this article, whereas certain other rotary piston blowers and single-screw compressors are often used in lower pressure, high-volume applications. These machines represent a sub-set of the machinery group making up rotating positive-displacement compressors. For both dry screw and wet screw compressors, typical rotor profiles are shown in Fig. ![]() The point of this two-part article is to alert the reader to the (often considerable) merits of twin-screw rotary compressors and to set the record straight on wet screw machines. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |