Inverter screw compressor energy analysis and selection

Screw compressor energy depends on four factors

First, the design

Screw compressor rotor profile has a certain impact on energy , in 2000 before the screw compressor is still growing, reliability is a major problem . Then screw compressor rotor profile development as the main target of the reliability .

21st century energy crisis enveloped the world , screw compressor rotor profile developed on the basis of the reliability of the energy as an important goal . SKK type line is in this environment resulting in outstanding energy-saving lines. SKK -type line using curved surface facing the inner seal , in the same space , the yin and yang between the rotor seal is much better than using the traditional wire line sealed .

Second, the head manufacturing

Yin and yang between the rotor and the rotor and the gap between the cylinder and the cylinder head for screw compressors have a significant impact on energy consumption . Rotor improve machining accuracy and surface finish is to reduce the gap between the head of each component effective means. SKK type line with grinding means for the realization . Therefore, surface grinding machine must be used . British Precision Machinery Co., Ltd. production with real-time detection and automatic compensation of grinding wheel surface grinding the rotor machining accuracy increased to unprecedented levels.

British Precision Machinery Co., Ltd. is SKK grinder type line processing is provided after 2006 the latest generation machine tools, processing capacity up to 370mm in diameter , precision up to 2 microns , finish up to 10 . Prior to such a large screw compressor rotor milling machine can only use a maximum precision of 40 microns , finish up 6 .

Third, screw machine configuration

Male screw compressor rotor speed is a measure of energy , life and reliability of the most important parameters. Belt drive 5% of the power loss , loss of power, gear shift of 3% , the screw compressor energy premise must be equal to the male rotor speed motor spindle speed at 50Hz power system is under the male rotor speed is equal to 1485 rev / min or equal to 2985 rpm / min.

The male screw compressor life is inversely proportional to the rotor speed stringent .

Fourth, the use

Screw compressor motor power consumption when idling for 30 % to 40% , some conditions when the screw compressor efficiency drops about 5%. All screw compressors are designed for a specific operating conditions , and in accordance with the design conditions of operation, the most energy-efficient screw compressors .

When the screw compressor gas production continued consumption equal to the pipe network , the screw compressor is the most energy efficient state.

Inverter compressor energy analysis

1 , the inverter ’s own consumption 3 % of the power , the motor rated power and rated speed deviation from the efficiency decreased significantly , screw compressor speed deviation from the rated speed optimum oil mixing ratio is destroyed, there was a marked decline in efficiency . Therefore, the use of frequency screw compressor , even though the last is equal to the pipe network gas production consumption , but the production of compressed air per cubic increased power used . In other words, in the continuous loading conditions, the inverter screw compressor is not energy efficient.

2 , most of the screw compressor use cases , changing the pipe network consumption , gas production can not be identically equal to the compressor pipe network consumption , when the pipeline pressure is equal to the set value, the screw compressor into the no-load condition , screw compression machine idling motor nominal power consumption 30% ~ 40 %, so when idling screw compressor efficiency is very low. Reduce or avoid idling time to enter idle state screw compressors have a certain energy-saving effect .

3, frequency screw compressor can effectively reduce the idle time or avoid screw compressor into the idle state , so the compressor Rated gas consumption is greater than the pipe network when there is a certain screw compressor inverter energy-saving effect .

4 , frequency screw compressor to stabilize the pipe network pressure is very effective , you can make the pipe network pressure stabilized at ± 0.01MPa range - which is the other way flow control is difficult to achieve.

Air Station Configuration

Energy-saving compressor station configuration principles are:

1 , equal to pipe gas production continued consumption ;

2 , a single compressor or at nominal operating conditions or in a shutdown state.

According to statistical analysis of the results to the pipe network Consumption assigned to more than one compressor , so that a larger portion of the compressor to provide constant gas ; several smaller compressors with gas consumption change according to operational or stop running , using a variable speed compressor , and further fine-tune the air supply.

Screw compressor waste heat has great value in use , energy-efficient compressor station should be fully considered waste heat recovery and utilization.