Research On Technology Of Field Dynamic Balancing Without Trial Weights

Safe operation of high speed rotating machinery in petrochemical industry has been the widely watched.High speed rotating machinery was more affected by material, shock, corrosion, wear, coke, wich will cause unbalance fault of rotor system of the machine.While70%of rotating machinery vibration fault comes from the imbalance of the rotor system.Typically, for large vibration of rotor,maintenance personnel replace the impeller directly, with run after reinstalling, to achieve the purpose of reducing vibration.However, due to the original unbalance of rotating parts, while the machine is running the, sometimes allowed values of the vibration still exceeded the standard.In order to prevent to destroy the machine, the normal operation safety and safeguard of personnel, must carry on the balancing correcting.Balancing correction is divided into three methods:balancing machine balance correction, field balancing correction, on-line balancing correction.Three types of dynamic balance technology, balancing machine balancing technology origins is earlier, and is the most mature.But the adjustment step is troublesome, the consumption financial resource, the physical resource, the manpower are big.Online dynamic balance technology for machine downtime situations, through the sensor test, balance correction directly after the diagnosis.However, this technique requires a precise balance correction execution mechanism, subject to the limitations of working space and cost constraints for many machines;At this stage, for the rotating machinery of petrochemical enterprises,field balancing technology has the largest advantages.On the one hand, field balancing technology solves the rotor disassembly of trouble; according to field conditions, the actual rotor vibration facilitates accurate troubleshooting.The troubleshooting can be completed in a short period of time using the technology,with resume production and greatly reducing operational risk and loss of corporate security.On the other hand, the technology cost is lower than the other two techniques,more in line with the demand of petrochemical enterprises at this stage.But at present, field balancing techniques generally require testing of the original vibration of the rotor system as well plus test weight after vibration to diagnose the magnitude and phase of the original amount of unbalance, and then balance correction, in order to achieve the purpose of reducing vibration.The process of the process of trial weight is often require repeated, which led to many open downtime.Production normal, continuous operation has brought some difficulties.At the same time for large equipment, each time of the shutdown the economic losses are huge, sometimes conditions were not allowed.To solve this problem, field balancing technology without trial weights is researched and proposed a new approach to achieve the purpose.This article on base of years of laboratory research on dynamic balancing technology, which the two balance disc is designed as a balance mechanism, with two plane dynamic balancing method, by adding a counterweight, field balancing technology without trial weight is explored.Of this approach is proposed, without trial weight process, which achieved only a shutdown plus counterweight to achieve balance correction effect.Avoid at the site dynamic balance correction process, the need of trial weights to find the original unbalance.Through theoretical analysis and experimental research,exploration,draw the following conclusions:1.The size of the hole on the balance discs as well as balance discs installation positions, has a lot of influence to balance correction effect.Balance hole is too small, the large amount of unbalance can not to be corrected.Balance hole is too large, the small amount of unbalance can not to be corrected.Two balance discs install are away from in a big way, easy to realize the balance adjustment.2.Lay out of dynamic balance of balance weight has little effect in correction Comparison, symmetrical layout has a better correction effect.3.In the case of large stiffness of rotor system supports, the linear of many of vibration parameters is not good,while average showed good linearity. 4.There is little effect of the correction of the change in rotational speed for different size balancing counterweight.5.Derivation proceeds based on the relationships between unbalance and balance weights, as well as the two plane balancing principle, by adding to the rotor system balancing mechanism,the rotor system can be realized dynamic balance on site without trial weights.The techniques have been proven to be good effect. There are some reference value to further exploration and study.