Energy efficiency rating is not the primary condition, it is more economical for air compressors to do so!

Energy efficiency rating is not the primary condition, it is more economical for air compressors to do so!

This article tries to discuss how to improve the operating efficiency of air compressors, reduce production costs, and help customers improve economic benefits.

　　Improve the operating efficiency of the air compressor

　　 (1) Reasonable selection

　　 It is undeniable that the current stage of the air compressor market is focusing on high energy efficiency and low energy consumption. However, the selection of air compressors and energy efficiency levels are not the primary conditions. In fact, the basic criteria for the selection of air compressors is safety, reliability, and economy at the end, and then the specific selection is carried out on this basis.

　　 The more scientific selection steps are: working pressure-volume flow-power supply capacity.

　　First, work pressure. Determining the required working pressure of the gas end is the primary consideration for air compressor selection. What needs to be considered is the reduction of pressure loss caused by pipelines and post-processing equipment;

　　Second, volumetric flow. First, fully and systematically understand the volumetric flow of all gas equipment. And multiply the volume flow of all equipment by 1.2;

　　 Third, power supply capacity. The volume flow of the air compressor has nothing to do with the working pressure and the power change of the air compressor, but is related to the change of the speed. After the air compressor speed changes, the exhaust volume will also change accordingly.

　　 Before selecting the air compressor, it is necessary to focus on the volume flow and working pressure, and select the power of the air compressor. At the same time, the power supply capacity needs to meet the power requirements of the air compressor.

　　 At present, many companies need to update and transform old equipment. Nowadays, many factories, especially large and medium-sized enterprises that have been established for more than ten years, use complicated air compressor equipment models, some of which are old products, which consume high power, difficult to reserve spare parts, and have a large amount of maintenance. Many of the operating efficiency of old equipment is less than 60% of the rated displacement, not to mention the latest energy-saving air compressors. However, due to the inconspicuous parallel connection of multiple devices, it has not been paid attention to. Some companies believe that reducing their production costs means cutting equipment maintenance and renewal investment, rather than renewing and transforming old equipment.

　　 Do you know that the operating cost of an air compressor consists of three items: initial purchase cost, maintenance cost and energy cost. The energy cost accounts for about 77% of the operating cost of the air compressor. If the old equipment currently in service can be updated into a high-efficiency and energy-saving air compressor, the energy savings will be considerable. At worst, necessary energy-saving transformations can be made to the air compressor. This will not only reduce the no-load operation time of the equipment, but also reduce the impact on the air compressor and the wear of the motor bearings, reduce the amount of maintenance and repair, and greatly reduce Operating costs.

　　 (2) Improve the operating efficiency of air compressors

Corresponding to the fact that some companies do not update and replace new energy-saving air compressors, although some companies choose air compressors with high energy efficiency levels, they do not pay attention to maintenance and maintenance, nor can they maintain good equipment operating habits, which certainly cannot guarantee air compressors. The press runs efficiently. To improve the operating efficiency of the air compressor, the main thing is to strengthen the maintenance and overhaul of the equipment. At the same time, pay close attention to the cooling effect of the air compressor, and the intake air temperature should not be too high. Through practical tests, every time the intake air temperature increases by 3°C, the efficiency of the air compressor will decrease by 1%. If you can ensure that the air compressor is always in a good lubrication state, you can reduce the friction resistance and effectively reduce the power loss caused by mechanical friction.

　　 Reduce the failure rate of the auxiliary equipment of the air compressor

　　 Air compressor auxiliary equipment mainly refers to cooling water, electric control equipment, etc. Reducing the failure rate of these auxiliary equipment and improving power-saving operation have a very positive significance for improving the operating efficiency of the air compressor and reducing the operating cost.

The cooling system of air compressor mainly has two kinds of air cooling and water cooling. For water cooling systems, the temperature, pressure, cleanliness, and hardness of the cooling water will affect the effectiveness of the cooling system. Generally, a cooling tower is used to provide cooling water, and the water pump is circulated to the air compressor after being filtered. It should be noted that the time interval for cleaning the cooling tower should be determined according to the on-site environment. If the site is dusty, the time for clearing the cooling tower should be shortened.

　　 At the same time, it is generally required that the inlet water temperature does not exceed 30°C and the outlet water temperature does not exceed 40°C. However, some companies tend to be cheaper, purchase pumps with low efficiency, and consume a lot of power. This may have a negative impact on the economic efficiency of air compressor operation. Therefore, it is recommended that users choose more efficient cooling water pumps.

　　 Reduce compressed air pipeline loss

In the process of compressed air passing through the pipeline to reach each point of use, friction between the air flow and the pipeline and its accessories will create resistance, which will inevitably cause the loss of compressed air pressure. This requires increasing the exhaust pressure of the air compressor. Make up for the pressure drop loss in the pipeline and indirectly increase the operating cost of the air compressor.

　　 Under normal circumstances, the size of the pipeline diameter is inversely proportional to the pressure loss of the air compressor, and the size of the turning point is directly proportional to the pressure loss of the air compressor. Therefore, when the distance between the air compressor and the gas terminal is too far, the diameter of the main pipe needs to be appropriately enlarged. If conditions permit, an air compressor can be installed nearby.

　　 In addition to resistance, compressed air leakage is almost the most common type of energy waste for end users. According to statistics, the average compressed air leakage accounts for 30% of the entire compressed air volume. In the factory, some leaks are very obvious. Not only does it emit a lot of noise, it can even be detected by touch and vision. And some leaks are very concealed. Except for small and difficult to hear sounds, "concealed" leaks are often covered by loud noises in the workplace.

　　According to the survey results of the United States Department of Energy (DOE) and the long-term experience of industry professionals, there are leaks in every compressed air system, and nearly 60% of the factories have not taken any effective measures against leaks in the air system.

　　 Compressed air leakage usually occurs in the following places: pipe joints, quick-connect fittings; pressure regulator (FRL); often open condensate drain valve; broken hoses, broken pipes. Therefore, it is necessary for users to strengthen pipeline maintenance and keep pipeline joints air-tight. Pipe joints should be welded as far as possible; an oil-water separator should be appropriately added to prevent water accumulation in the pipeline and improve gas fluidity.

　　In practical applications, some local shape restrictions and pipeline control needs are indispensable, but the installation of three-way, elbow, gate valve and other accessories in the pipeline will cause great pressure loss. According to research, the pressure loss of an angle valve with a diameter of 50mm is equivalent to the pressure loss of a straight pipe with the same diameter of 13m. Therefore, these accessories must be used as little as possible, and the pressure loss of all accessories must not exceed 10% to 20% of the pipeline.

When the pipeline has to be lengthened, there are many branches, and accessories are indispensable, the diameter of the pipeline can be increased to reduce pressure loss and reduce the burden on the air compressor (pressure loss is inversely proportional to the square of the pipe diameter), otherwise it is empty The press may be fully loaded or even overloaded for a long time, reducing the service life of the equipment.

　　 However, it is almost impossible for a factory to completely eliminate the leakage. What we can do is to try to control the leakage of compressed air within a reasonable range. This "reasonable" range and the scale of the factory have a great relationship with the old and new: for new systems (less than 1 year) or small factories, the leakage rate is controlled between 5% and 7%; for systems that are 2 to 5 years old Or medium-sized factories, the leakage rate is between 7% and 10%; for systems or large factories over 10 years, the leakage rate is between 10% and 12%.

　　The combination of people and system improvement

　　 In order to improve the operating efficiency of air compressors and reduce operating costs, in addition to tapping the potential of the equipment itself, it is necessary to work in many ways. One is to improve the professionalism of operation and maintenance personnel. Only with excellent professional knowledge of air compressors and relevant equipment operation and management experience can fundamentally ensure the good operation of air compressors.

　　The improvement of the system is to indirectly improve the overall efficiency of the air compressor equipment, reduce operating costs and economic losses due to failures, by formulating relevant training systems, maintenance systems, duty systems, spare parts inventory systems, and rewards and punishment systems.