CMN Technology Co.,Ltd.
CMN Technology Co.,Ltd.

CMN 40bar oil-free screw compressor VS Oil-free reciprocating piston compressor

Compared with the medium-pressure oil-free piston machine, the CMN medium-pressure water-lubricated pure oil-free screw compressor has the following six obvious advantages, as follows:

1. Low energy consumption

Compared with the piston machine, under the same working conditions, the energy saving of the CMN screw machine can reach more than 10%, and with the continuous wear of the piston ring and the inner wall of the cylinder during the use of the piston machine, this energy saving ratio will gradually increase to 15%~30%, or even higher. Taking an air compressor with an installed power of 250KW as an example, the energy consumption saved by running an average of 6,000 hours per year:

 250KW*6000H*0.15~0.3=225,000~450,000 kWh, the industrial electricity fee is 0.8 yuan/kWh, and the electricity bill saved every year : Between 180,000 and 360,000 yuan, the entire life cycle of the air compressor is calculated as 20 years, and the loading rate is calculated as 80%, the total electricity cost saved is 2,880,000 to 5,760,000 yuan.

CMN screw air compressor China:

1、The air end  has compact and simple structure, high processing and assembly precision, no clearance volume, adopts IE4 level high-efficiency permanent magnet variable frequency motor, the compression efficiency can reach more than 95%, and the fluctuation value of the air supply pressure can be accurately controlled within 0.5Bar;

2. The air end and the motor are directly connected with high transmission efficiency, low power loss, high speed and light load, and adopt the world's first two-stage double-drive permanent magnet frequency conversion design, which can always maintain the best input ratio power of the intelligent control system under different pressure and gas consumption conditions.

Piston air compressor:

1. The structure is bulky and complex, low-speed and heavy-load, and the leakage of piston ring wear increases between two maintenance, resulting in a continuous increase in specific power. When the variable frequency technology is used to reduce the linear speed of the piston, since there is no sealing medium, the increase of internal leakage per unit time makes the energy saving effect not ideal;

2. When the piston reaches the dead center, VO1 between its end face and the cylinder head, the annular gap VO2 between the piston end face and the first piston ring, and the entire channel VO3 between the cylinder end face and the valve plate, The existence of the clearance volume reduces the exhaust volume of the compressor, which causes the delay of the suction process and the reduction of the suction volume.

2. Simple maintenance and low cost

The annual maintenance cost is at least 100,000 yuan lower than that of the piston machine with the same displacement, and it will save about 2.6 million yuan in the entire life cycle (take the 25m3/min model as an example).

CMN screw air compressor:

There are no wearing parts, just replace the air filter element, water filter element regularly and add grease to the motor and the bearing of the air end. The annual maintenance cost generally does not exceed 20,000 yuan.

Piston air compressor:

Taking a 25 m3/min oil-free piston machine as an example, the maintenance cost for 6,000 hours is usually more than 150,000 RMB. The entire life cycle of the air compressor is calculated as 20 years, and the maintenance cost exceeds 3 million RMB. Other conventional accessories of the piston machine are not counted.

The cost savings of the above one and two items add up to a total of 5.48 to 8.36 million yuan.

3. Small vibration, low noise, great safety

CMN screw air compressor:

1. The air end adopts a single-screw double-meshing pair symmetrical structure, which runs smoothly, with little vibration, and the vibration intensity is less than 4.5m/s (a coin can be placed on the air end without falling down during operation), and the installation is simple and fast without fixing the foundation, and maintenance does not require lifting;

2、The noise generally does not exceed 80dB(A), and it can be placed in the workshop for open use. It can be installed nearby to reduce the installation cost of compressed air solution pipes and valves, reduce pressure drop and pipe loss, and do not need to build an independent air compressor room;

3、The temperature of the compression chamber and the exhaust gas is lower than 50°C, which improves the service life of the seal and makes the working environment safe and comfortable.

Piston air compressor:

1、The vibration is large during operation, and it needs to be installed on a fixed foundation. At the same time, due to the reciprocating movement of the piston, the exhaust is not continuous, and the air flow has pulsation, which is easy to cause pipeline vibration. In severe cases, the pipe network or parts are often damaged due to air flow pulsation and resonance;

2、The noise is high, generally higher than 100 dB(A), an independent compressor room is required and required to be built away from residential areas;

3、The temperature of the compression chamber is as high as 160-180°C, which reduces the service life of the seals, and the operator has potential safety hazards of burns. The high temperature of the air compressor room requires the installation of a large exhaust fan for ventilation and heat dissipation.

4、100% Oil free guarantee

CMN screw air compressor:

1、Environmentally friendly The whole machine does not use a drop of lubricating oil, and the internal circulating water plays the role of lubrication, cooling, sealing, cleaning, noise reduction, etc., ensuring that the compressed air is 100% oil-free, and the oil content is truly 0ppm (in the state of oil-free air intake, Imported oil-free detectors can be provided for on-site testing);

2、The full series of CMN oil-free compressor in China have passed the German TÜV class 0 oil-free certification.

Piston air compressor:

1. The crankcase of the machine needs to be regularly filled with lubricating oil and a certain pressure must be ensured (with an oil pump, the working pressure in the crankcase is 2-3bar, and the oil temperature is around 90°C) to force lubrication of crankshaft, bearing bush and connecting rod, When the oil scraper ring and stuffing box that prevent lubricating oil from entering the cylinder are worn out, the lubricating oil will enter the cylinder in gaseous or liquid form, resulting in the discharge of compressed air containing oil, which has the risk of oil contamination of the production line, affecting the taste of the product and endangering personal health if machine is used for food manufacturing;

2. The disposal of waste lubricating oil increases the cost and pollutes the ecological environment at the same time.

5、High cleanliness of compressed air

CMN air compressor:

1. The water washes the air thoroughly, and the fine particles (3-5μm) remaining in the air stay in the water after being filtered, and are discharged by the automatic drainage valve. At the same time, SO2, NO2, H2S and other harmful gases contained in the air are absorbed into the water, discharged out of the body through the automatic drainage and sewage valve, and completely removed when the internal circulating water is replaced regularly

2. All parts in contact with water and air, such as air end, pipeline, filter, water vapor separation barrel, cooler, etc. are all made of 304 or 316 food-grade stainless steel, which is safe, clean and hygienic.

Piston air compressor:

1. Fine dust particles sucked in with the air, foreign matter such as friction and falling off of moving parts, and harmful gas components in the air are discharged as much as they are. Coupled with the pollution of compressed air lubricating oil, the burden on post-processing filters and refrigerated dryers increases until normal processing is affected.

It increases the risk of contaminating products entering the blowing system, which in turn endangers the health of consumers and poses a threat to food safety.

2. Most of the parts in contact with water and air: cylinders, pistons, pipelines, coolers, etc. are made of ductile iron, cast iron, aluminum or forged steel, which are easy to corrode and rust (visible during major maintenance), Thus, the compressed air is polluted, and the discharged compressed air contains rust and other peculiar smells. At the same time, most of the corroded parts need to be replaced after several years of use, which increases the cost of use.

CMN screw air compressor:

Exhaust temperature < 50°C, due to the lower temperature, the water content is relatively low (the lower the compressed air temperature, the lower the water content in the gas), After being treated by a refrigerated dryer, the dew point can easily reach below 10 degrees, and the burden on the refrigerated dryer and filter is small, ensuring the safety of gas used in the blow molding machine.

Piston air compressor:

The working temperature of the compression chamber is about 150~180°C, the exhaust temperature after the cooler is about 85°C, the water content of the compressed air is high (the higher the temperature of the compressed air, the higher the water content in the compressed air), It increases the burden on the refrigerated dryer and filter, and also increases the energy consumption. If the filter of the refrigerated dryer is not maintained and replaced in time, the water content in the compressed air will be too high, which will affect the quality of the bottle blowing (the smoothness, transparency, and internal blemishes, etc.).