md280-65 multi-stage centrifugal pump works: reciprocating pump applications than centrifugal pumps, but its variety is unmatched heterogeneous, diverse structure, md multistage centrifugal individual energy end and fluid end by the two departments. md multistage centrifugal pump based on a different structure, ordinary cylinder number (linking number), and the role of method to divide the common situation of structural horizontal triplex single acting piston pump, featuring single-acting piston pump, two-cylinder double-acting piston pump. md multistage centrifugal main structural components: motor, coupling, reducer, drive end parts, fluid end local public base, rod with sealing. md280-65 multi-stage centrifugal pump machine: the forward section of water, the water segment, backward section of water, guide vanes, the right guide vanes, water segment left guide vanes, the right guide vanes of the water segment, middle, impeller, right impeller shaft the balance drum, before positioning sleeve, after positioning sleeve, bridging frame commutation flow channel; MD multistage centrifugal pump rotor by an impeller mounted on the shaft, the right impeller, balanced drum, the impeller stopper sleeve before positioning sleeve, after locating bush and other component parts, rotor drive end with a roller bearing support, the end of back-to-back arrangement using a pair of angular contact ball bearings, md multistage centrifugal pump bearing grease smooth. When we see this article to make use of instant messaging (QQ or telephone) contact us .. Changsha Huali Pump. 280-65 wearable multi-stage centrifugal pump mechanical characteristics 1.1 mechanical characteristic equation so far recognized scholars wear multistage centrifugal pump mechanical characteristic equation is: tl = t0 + ktnl2 (2), tl-wear-resistant and more stage centrifugal pump of the load torque, N? m; the t0-wearable idle torque of the multi-stage centrifugal, n? m; KT-torque proportioning constant; NL-wear-resistant multi-stage centrifugal pump speed, r / min. Idle torque of the formula (2) include: loss torque and wear of the friction torque of the motor itself and ventilation torque transmission mechanism of the multi-stage centrifugal friction torque and the like. Due to the smaller proportion, at a rough estimate can be negligible, while: tl ≈ ktnl2 (3) Therefore, the wear-resistant multi-stage centrifugal pumps are often referred to as the quadratic law load. 1.2 actual head in mechanical characteristics reflect the wear-resistant multi-stage centrifugal pump shaft input mechanical power, proportional to the product of the torque and speed: PL (4) wherein PL-motor output shaft power, is also the wear multistage centrifugal pump input power kw. Where the formula (2) into equation (4), too: pl == + = p0 + kp nl3 (5), p0-no-load power kw;-kp-power ratio constant. If p0 is negligible, the shaft power can be roughly expressed as: PL ≈ KP NL3 (6) 1.3 Generalized unloaded power supply systems, the basic power pa is actually not really water supply before the loss, generalized to say, is also a no-load loss. So, as the drag of a piped water supply systems, there is a broad-load loss: p0a = p0 + pa (7)-water supply pipes in p0a broad no-load loss kw. The essence of the generalized-load loss is water supply pipeline in the basic loss the shaft power a feedback. Therefore, simple to use (3) and (6) to illustrate wear multistage centrifugal energy-saving effect is biased. Two wear-resistant multi-stage centrifugal pump input and output power differences in the energy saving effect of the 2.1 fluid power law in practical applications, the wear-resistant multi-stage centrifugal pumps the working frequency is generally not lower than 25Hz, therefore, the lower the frequency, the energy saving effect is more A good argument is moot. 2.2 shaft power the law of the energy-saving effect (1) to adjust the speed when the power curve of the relative value of the flow: Q * (8) formula, q * - The flow rate of the relative value; q-actual flow rate, m3/min; the QN-rated traffic , m3/min. A relative value of the speed: n * (9) of formula, the n * - The speed of the relative value; n-actual speed, r / min; NN-rated speed, r / min. A relative value of the power: p * (10), p * - power relative values; p-actual power, kW; pn-rated power, kW. (2) adjusting the valve opening of the power curve to adjust the flow by adjusting the valve opening, the motor at full speed running. When the valve opening degree is reduced, the motor shaft power has also been reduced, but decrease a little. (3) the energy conservation law, assuming a relative value of the actual flow qb *, when realized by reducing the speed, the power consumption relative value Pb *; realized by closing the small valve opening degree, the relative value of power consumption is pc *. The comparison of the two methods to adjust the speed can save power δp of *. Flow (speed) is smaller, the greater power savings. This law and fluid power energy saving law clearly inconsistent. The difference between 2.2.3 wear multistage centrifugal efficiency of fluid power and shaft power is to wear multistage centrifugal efficiency: the formula pg = pl? Ηp (11), pg-fluid power, kw; pl- shaft power kw; ηp-wearable multi-stage centrifugal pump efficiency. According to the information, the wear multistage centrifugal efficiency relative value ηp * approximate calculation formula is as follows: where ηp * = c1 ()-c2 (12), ηp * - wear multistage centrifugal pump efficiency relative value ; q * - flow of the relative value; n - rotational speed of the relative value; C1, C2 - constants provided by manufacturer. between c1 and c2, usually follow the following rules: wear multistage centrifugal pump efficiency speed c1-c2 = 1 (13) (1) adjust the valve opening constant, flow q * and speed n * is proportional to: q * / n * = 1 so: ηp * = 1 So, the speed control, wear multi-stage centrifugal pump efficiency is always at its best. (2) adjusting the valve opening degree of abrasion-resistant multi-stage centrifugal pump efficiency when by turning small valve to adjust the flow q * Since the speed constant, n * = 1, therefore the ratio q * / n * = q *. Substituting (12 may: ηp * = c1 / q *-c2q * 2 (14) to regulate the flow regulating valve opening, the wear multistage centrifugal efficiency decreases with decreasing flow.