Compressors classification

Industrial Centrifugal Compressor Classification Based on Casing Design... 

Based on the different gas compression principle compressor can be classified into three types dynamic, positive displacement, and thermal type. See Figure 1 for the general compressor classification. 

The compressor or blower installation in a typical refinery or chemical process unit is not out-of-doors completely. Some form of shelter often is provided, ranging from only a roof to a completely closed building. When process equipment such as a centrifugal gas compressor, which is not hazardous in normal operation, is present in the shelter, the hazard classification depends on the extent to that which the shelter restricts ventilation. The extent of the shelter provided determines the area classification and the type of motor enclosure that should be applied. 

Classifications 477. Standard Units 481. General Calculations 481. Reciprocating Compressors 484. Rotarv Compressors 487. Centrifugal Compiessors 493. Axial-Flow Compressors 494. 

A compressor is a machine that is used to increase the pressure of a gas or vapor. They can be grouped into two major classifications centrifugal and positive displacement. This section provides a general discussion of these types of compressors. 

Positive-displacement compressors can be divided into two major classifications rotary and reciprocating. 

There are two basic types of compressors (1) centrifugal and (2) positive displacement. Both of these major classifications can be further divided into sub-types, depending on their operating characteristics. This section provides an overview of the more common centrifugal and positive-displacement compressors. 

The recommendations of the International Standards Organization (ISO) covering mineral-oil lubricants for reciprocating compressors are set out in ISO DP 6521, under the ISO-L-DAA and ISO-L-DAB classifications. These cover applications wherever air-discharge temperature are, respectively, below and above 160°C (329°F). For mineral-oil lubricants used in oil-flooded rotary-screw compressors the classifications ISO-L-DAG and DAH cover applications where temperatures are, respectively, below 100°C (212°F) and in the 100-110°C range. For more severe applications, where synthetic lubricants might be used, the ISO-L-DAC and DAJ specifications cover both reciprocating and oil-flooded rotary-screw requirements. 

The several kinds of commercial compressors are identified in this classification ... 

To simplify industrial lubricant classification, the names of lubricants such as bearing lubricants, compressor lubricants, hydraulic lubricants, gear lubricants, metalworking lubricants, etc., derive from their application. These classifications are consistent with other lubricant categories, i.e. lubricants for internal combustion engines, aviation lubricants and marine lubricants. 

Compressors can be divided into three classifications centrifugal, rotary, and reciprocating. This section identifies the common failure modes for each. 

In the classification of compressors presented in Figure 4.24, five different types of positive displacement compressor are included. The constant speed operating characteristic of each of these is similar to that shown in Figure 4.25. A particular feature of most of these machines is that very fine operating clearances are maintained between rotating parts. As a result there is no possibility of the conveyed material being conveyed through the... 

---