How to prolong the service time of high viscosity

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How to prolong the service time of high viscosity gear pump

selection of transmission medium transmission medium is not only the intermediary of energy transmission, but also the medium of lubrication, sealing and heat transfer. The gear pump conveying high viscosity liquid should output the most flow under low power consumption, less leakage and larger pressure. The viscosity of the liquid reflects the difficulty of the medium flow. Too high viscosity will increase the internal friction resistance, reduce the output power, and waste the energy specified in the product manual. Try to use the fluid medium recommended by the manufacturer, pay attention to the quantity, and produce too high system temperature. When determining the medium to be transported, the working temperature range of the system should be strictly followed and considered. When you want to use it in a wide temperature range, the viscosity index of the transmission medium should be higher. The multi interconnected robot system can maintain a high working tension

when the viscosity of the conveying liquid is high, or when the system works in a cold environment, it must ensure that the conveying medium can flow smoothly. Many oils contain waxy components, which are easy to crystallize at low temperature. The freezing point of the transmission medium should be lower than the expected minimum operating temperature. In addition, the medium to be transported must be compatible with the rubber materials such as seals, gaskets and hoses in the system. If the two are incompatible, the medium to be transported must be redefined

noise problem in the fluid conveying system, the rapid changes of liquid flow velocity, flow and pressure, bubble rupture and alternating load are common causes of noise, and the gear pump conveying high viscosity liquid is the main source of system noise

reasonably determine the working speed of the gear pump, so that the rotation of the gear and the shaft can avoid the meshing resonance frequency, which can prevent the noise from intensifying. Because resonance is easy to occur when the meshing frequency is close to the natural frequency of the gear train. Proper vibration isolation technology can prevent vibration from being transmitted to adjacent structures. Therefore, the gear pump and the drive motor should be connected through a flexible coupling and installed on the same base plate to ensure coaxiality. The base plate installed on the elastic support can further improve the vibration isolation effect. Setting an expansion chamber or accumulator on the outlet pipe of the gear pump to absorb the pressure pulsation of the pump or buffer the sudden change of pressure in the pipeline is an effective means to control the noise of high viscosity gear pump

generally speaking, the maximum allowable noise of a high viscosity gear pump working in the open air should be less than 90 dB, otherwise the noise source should be actively or passively restrained, and the working time of workers directly exposed to the noise environment should be reduced. If the noise cannot be controlled, hearing protection measures should also be taken. In case of abnormal noise during the operation of high viscosity gear pump, it should be shut down immediately for inspection

working pressure the rated pressure of the selected pump refers to the maximum allowable pressure when the pump works continuously, and its working pressure depends on the external load, and the service life of the pump is directly related to its working pressure. For gear pumps that do not work frequently, the working pressure can be taken as the rated pressure of the pump. Considering the different product quality, it is best to reduce the rated pressure by 20% - 30%. For gear pumps that often work under high pressure, the working pressure should be 1 ~ 2 pressure levels lower than the rated pressure of the pump. Petrochemical equipment often operates continuously for 24 hours. At this time, the working pressure of the pump should be much lower than the rated pressure, and the working speed should also be lower than the rated speed. If the working pressure of the high viscosity gear pump is adjusted too high, the gear pump will run under overload

the support or flange of the high viscosity gear pump for installation and test run and its drive motor shall adopt a common installation foundation, and the foundation, flange or support shall have sufficient stiffness to reduce the vibration and noise generated during the operation of the gear pump. The motor and gear pump must be connected by elastic coupling, with coaxiality less than 0.1 mm and inclination angle not more than 1 degree. Do not knock with a hammer when installing the coupling, so as not to damage the gear and other parts of the gear pump. If it is driven by belt pulley, sprocket, etc., bracket support shall be set to prevent radial force on the driving gear bearing. When fastening the anchor screws of gear pump and motor, the screws should be stressed evenly and connected reliably. When rotating the coupling by hand, you should feel that the gear pump can rotate easily. 1. The fluctuation range of power supply voltage should not exceed ± 10% of the rated value, and there is no abnormal phenomenon such as clamping, and then you can pipe. The inner diameter of the oil suction pipe of the high viscosity gear pump should be large enough, and narrow channels or sharp bends should be avoided, elbows should be reduced, unnecessary valves and accessories should be removed, the installation height of the pump should be reduced as much as possible, and the length of the oil suction pipe should be shortened to reduce pressure loss. Components such as pipe joints should be well sealed to prevent air intrusion, so as to control the occurrence of cavitation and cavitation

before starting the operation, fill the shell of the gear pump with the liquid to be delivered for safe start. If the ambient temperature is lower than the freezing point, warm steam should be introduced into the pump in advance for preheating, and then the gear pump can be started. The rotation direction of the gear pump should be consistent with the oil inlet and outlet. If the gear pump is operated for the first time or used after being idle for a long time, it is best to run it for an hour under no-load or small load. I know that when the high and low temperature test box is used for a long time, it will be around. If abnormal temperature rise, leakage, vibration and noise are detected in advance during the running in phase, the machine shall be shut down for inspection

check valve and safety valve it is best to install a check valve on the output pipeline of the gear pump. In this way, the liquid in the system will not flow back when repairing the pump and output pipeline. When the gear pump stops with load, it can also prevent the pump from reversing and generating local vacuum in its output pipe. It should be noted that the outlet check valve cannot be installed reversely or stuck

the outlet pipeline of the high viscosity gear pump should also be equipped with safety valves and other protective devices, so that once the pump is out, otherwise the hydraulic pump of the carton pressure testing machine will block the suction air inlet channel during operation, the safety valve can be opened for pressure relief. The safety valve can be cast into a whole with the pump body or pump cover, or it can be assembled separately. For high viscosity gear pumps requiring forward and reverse rotation, safety valves shall be set on the inlet and outlet pipelines

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