Automatic priming device for centrifugal pump

Abstract

The invention discloses an automatic priming device for a centrifugal pump. The automatic priming device mainly comprises a centrifugal pump, a gas-liquid separating tank, a liquid level sensor, a controller, an injector and a valve, wherein the gas-liquid separating tank is connected with a sucking port of the centrifugal pump, the liquid level sensor and a second pneumatic valve; the input of the controller is connected with the liquid level sensor; the output of the controller is connected with an electromagnetic reversing valve; the electromagnetic reserving valve is connected with a first pneumatic valve, the second pneumatic valve and a cut-off valve; and the injector is connected with the second pneumatic valve and is simultaneously connected with the first pneumatic valve through a one-way check valve. According to the automatic priming device disclosed by the invention, the function of automatically priming is achieved and the condition that no cavitation phenomenon always occurs in the operation process of the centrifugal pump can be ensured. In addition, the automatic priming device has the advantages of simple structure, low manufacturing and maintaining cost and stability and reliability in operation and is especially suitable for priming before the start of a ship ballast pump, a bilge pump and an emergency firefighting pump.

Description

technical field [0001] The invention relates to a water diversion device, in particular to an automatic water diversion device for a centrifugal pump without self-priming capability. Background technique [0002] The centrifugal pump belongs to the vane pump. If there is no water in it, the vacuum pressure cannot be established by the rotation of the vanes, and the water cannot be sucked in. Therefore, the centrifugal pump has no self-priming ability. However, centrifugal pumps are most suitable for ballast pumps, bilge pumps and emergency fire pumps. Above the line, it should also have self-priming performance. In order to solve the problem that the centrifugal pump has no self-priming ability, a self-priming device must be added to the pump. There are two common types of self-priming water devices: one is the jet pump type, which uses a solenoid valve to control compressed air as power to suck the air in the pump through the ejector to form a negative pressure. At the s...

AI Technical Summary

Problems solved by technology

The device has the advantages of self-priming function and can divert water for multiple pumps at the same time, but it has the following disadvantages: First, because the device controls the start and stop of the vacuum pump according to the vacuum degree of the vacuum tank, the vacuum degree is a relatively sensitive monitor object, put forward high requirements on the sensitivity of the monitoring components, and also have high requirements on the sealing of the vacuum tank, which brings certain difficulties to the selection design of the seal and the processing of the vacuum tank. If the vacuum tank has Leakage, the vacuum degree will be low, the chain reaction is the operation of the vacuum pump, correspondingly, it needs to consume electric energy, resulting in energy waste, and frequent start and stop will have an impact on the vacuum pump or the motor; the second is that the interface between the device and the pump is the exhaust of the pump. The steam port, if the suction port of the pump is close to the bottom of the liquid cargo, a large amount of gas is sucked in, the gas enters the pump first, and then is sucked away by the vacuum pump. At this time, the operation of the pump has been damaged, and it cannot play an early warning and protection role. , so it is not suitable for water diversion before the start of the ship's ballast pump, bilge pump and emergency fire pump; third, the device needs to be equipped with an "automatic exhaust water stop valve" to prevent the water in the pump from flowing backward into the vacuum tank, and only the water in the pump is allowed to The gas enters the vacuum tank, and the setting of functional components such as "automatic exhaust water stop valve" brings complexity to the device

Increased manufacturing and operating costs of the device

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