How to increase the air production volume of air compressors

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This post was last edited by ztj1118 on 2012-12-18 at 19:00. Users of compressors always choose the air compressor oil based on the maximum volumetric flow rate required by the device or system, yet the actual operating conditions of the compressor change according to the requirements of the production process or the equipment that consumes air. When the gas consumption is less than the compressor’s discharge volume, it is necessary to adjust the compressor’s gas output so that it matches the required gas consumption and helps maintain stable pressure in the piping system. The common methods for adjusting air volume in reciprocating air compressors include the following: speed control. Speed control involves adjusting the exhaust volume by changing the speed of the compressor. The advantages of this type of regulation include a continuous flow rate of air, lower power consumption, constant pressure ratios across the various stages of the compressor, and no need for specialized control mechanisms on the compressor. However, it is only widely used in compressors driven by internal combustion engines or steam turbines. If the drive is an electric motor, then an inverter is required. Due to the high cost of high-power, high-voltage inverters, as well as the extensive maintenance needs associated with them, this method is rarely used in reciprocating compressors driven by electric motors. Furthermore, variable speed control may have adverse effects on the operation of the compressor, such as valve flutter, increased wear of components and vibration, as well as insufficient lubrication of the air compressor, which also limits the widespread use of this method. Clearance chamber adjustment: On the compressor cylinders, in addition to the fixed clearance volume, there is an additional cavity. During adjustment, this cavity is connected to the working chamber of the cylinder, thereby increasing the clearance volume, reducing the volume coefficient, and decreasing the exhaust volume. This is the principle behind clearance chamber adjustment. Depending on the method of connecting to the supplementary volume, it is further divided into continuous, stepped, and intermittent regulation methods, which are commonly used in large-scale process compressors. The main drawback of this adjustment method is that it is usually adjusted manually and has a slow response time; it generally needs to be used in combination with other adjustment methods. Although the method of connecting variable compensating clearance volumes can in principle achieve adjustment within the 0% to 100% range, the system has poor reliability, many vulnerable components, and is difficult to maintain. Bypass regulation: The exhaust pipe is connected to the intake pipe through a bypass pipeline and a bypass valve; to carry out regulation, simply open the bypass valve, and part of the exhaust gas will return to the intake pipe. This adjustment method is relatively flexible and easy to implement; together with an automatic control system, it also offers high precision. However, since all the compression work required to compress the excess gas is lost, its economic efficiency is poor. Therefore, this method is suitable for occasional adjustments or those involving small amplitude adjustments. Adjustment by pressing the intake valve: Based on the length of time the intake valve is pressed, this method is divided into two types – full-stroke pressing of the intake valve and partial-stroke pressing of the intake valve. In the case of full-stroke opening of the intake valve for adjustment, during the intake phase, gas is drawn into the cylinder; during the compression phase, with the intake valve fully open, the gas that has been drawn in is pushed back out of the cylinder. Assuming that the oil sales center for screw air compressors in the north has a first-stage double-acting cylinder, if only the intake valve on one side of the piston is actuated, the air volume is reduced by 50%; if both sides are actuated simultaneously, the exhaust volume is zero. Therefore, this machine can achieve three levels of adjustment for air volume: 0%, 50%, and 100%. It can be seen that the adjustment range for fully pressing open the intake valve throughout the entire stroke is large, making it suitable for rough adjustment. The principle of adjusting by partially opening the intake valve is similar to that of fully opening it; however, by controlling the timing at which the intake valve closes during the compression stroke, it is possible to regulate the amount of gas returning, thus enabling continuous adjustment of the gas flow. Since the compression work decreases almost proportionally to the volume of exhaust gas, this approach also offers high operational efficiency.