Mechanical Component and Maintenance

Compressor

Introduction

This machine is broadly use in our everyday live where we can find in our homes and workplaces, and in almost any form of transportation we might use. Compressor serve in engines, chemical processes, gas transmission, manufacturing, and in just about every place where there is need to move or compress gas.

List of Application

Compressor are widely used by various type of industries and home appliance that depend on the power of compressor gas or fluid to power manufacturing processes in the industries. List the application of compressor such as;

• Air conditioners for car and home.
• Air pump.
• High pressure car washes.
• Hydraulic compressors for industrial machines.
• Air compressors for industrial manufacturing.
• Chemical/petrochemical plants.
• Ethylene plants.
• Gas lift/ gas gathering .
• Gas injection/ transport.
• LNG facilities 
• Gas to liquids.
• Ammonia plants.
• Power generator.

   Type of Compressor

It can be divided into two main categories;

1.Dynamic
2. positive displacement

COMPRESSOR

                 Dynamic                                              Positive Displacement

       Centrifugal                                                            Rotary

                                                                                     Reciprocating

Principal and Characteristic of Compressor

 Dynamic

• This type of compressor use the phenomenon of velocity to generate energy. 
• It happens by creating high speed energy through a rapidly moving piece. 
• The dynamic compressor is characterized by rotating impeller add velocity and pressure fluid.
• compare to positive displacement type compressor, dynamic compressor are much smaller in size and produce much less vibration.
• It widely used in chemical and petroleum refinery industry for specifies services.

Centrifugal Compressor

• A centrifugal compressor is a "dynamic" type of compressor.
• In a centrifugal compressor the mechanical energy is increased by centrifugal action.
• The gas enter the suction eye of a high speed rotary element called the impeller.
• The maximum pressure rise for centrifugal compressor mostly depends on the rotational speed(rpm) of the impeller and the impeller diameter.

Advantages

1. Reliable
2. Compact
3. Less plot area for installation for a given flow rate.
4. low maintenance costs
5. machine is small and light weight with respect to its flow rate capacity

Disadvantages

1. Very sensitive to changes in gas properties, especially molecular weight.
2. high initial cost
3. complicated monitoring and control system
4. high rotational speed require special bearing.
5. lower efficiency than most positive displacement type for the same flow rate.

Positive Displacement Compressor

  Rotary Compressor

• Rotary compressor is a group of positive displacement machines that has a central, spinning rotor and a number of vanes.
• The difference between each type is their rotating device.   

Advantages 

1. Simple design
2. low to medium initial and maintenance cost
3. Easy to install
4. Few moving part

Disadvantages

1. High rotational speed
2. single-stage designs have lower efficiency.

Reciprocating compressor 

• The reciprocating or also called as piston compressor, is another type of common positive displacement compressor.
• It can be considered as single acting, when it is using both sides of piston.
• This machine is used when high-pressure head is required at a low flow.

Advantages

1. Simple design, easy to install
2. lower initial cost
3. two stage models offer the highest efficiency.

Disadvantages

1. Many moving parts
2. Many are not designed to run at full capacity

        

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