PLUNGER PUMP

Plunger pump is an important device of hydraulic system. It depends on thereciprocating movement of plunger in cylinder block, so that the volume ofsealing working chamber changes to achieve oil absorption and pressure. Plungerpump has the advantages of high rated pressure, compact structure, highefficiency and convenient flow regulation.

Plunger pumps are widely used in high pressure, large flow and flow needs to beadjusted, such as hydraulic press, construction machinery and ships.

Mechanical classification

Single plunger pump

Mechanical classification

Horizontal plunger pump

Mechanical classification

Axial plunger pump

Mechanical classification

Hydraulic power element

Widely used

High pressure, high flow and flow need to be regulated

Mechanical classification

Plunger pump is generally divided into single plunger pump, horizontal plunger pump,axial plunger pump and radial plunger pump.

Single plunger pump

The structure consists of eccentric wheel, plunger, spring, cylinder block and twoone-way valves. A closed volume is formed between the plunger and the cylinderhole. The eccentric wheel rotates once, the plunger moves up and down once,moves down to absorb oil, and moves upward to drain oil. The volume of oildischarged from the pump is called displacement, which is only related to thestructural parameters of the pump.

Horizontal plunger pump

The horizontal plunger pump is a hydraulic pump which is installed side by side byseveral plunger (generally 3 or 5). A crankshaft is used to push the plungerdirectly through the connecting rod slider or by the eccentric shaft to doreciprocating motion to realize the suction and discharge of the liquid. Theyalso use valve flow distribution devices, and most of them are quantitativepumps. The emulsion pump in the hydraulic support system of coal mine isgenerally horizontal plunger pump. Emulsion pump is used in coal mining face toprovide emulsion for hydraulic support. The working principle is to drive plungerto do reciprocating motion by the rotation of crankshaft to realize liquidabsorption and discharge.

Axial

Axial plunger pump (Plunger pump) is a plungerpump whose reciprocating direction of plunger or plunger is parallel to thecenter shaft of cylinder block. The axial plunger pump works by the volumechange caused by the reciprocating movement of the plunger in the plunger holeparallel to the drive shaft. Because the plunger and plunger hole are roundparts, they can achieve high precision matching, so the volume efficiency ishigh.

Straight shaft inclined disc

Straight shaft inclined disc plunger pumpis divided into pressure oil supply type and self-absorbing oil type. Thepressure oil supply type hydraulic pump mostly uses the air pressure oil tank,depends on the air pressure oil supply hydraulic oil tank, after each start themachine, must wait for the hydraulic oil tank to reach the use air pressure,can operate the machinery. If the air pressure of the hydraulic tank isinsufficient, the machine will be started, which will cause damage to the bootsin the hydraulic pump, and will cause abnormal wear of the return plate and thepressure plate in the pump body.

Radial

Radial plunger pump can be divided intovalve flow distribution and shaft flow distribution. Valve distribution radial plungerpump has the disadvantages of high failure rate and low efficiency. The axialflow radial plunger pump developed in the 1970s and 1980s overcomes theshortage of valve flow radial plunger pump. Because of the characteristics ofthe radial pump structure, the axial distribution radial plunger pump hashigher impact resistance, long life and high control precision than the axial plungerpump. Variable stroke short pump variable is realized under the action ofvariable plunger and limit plunger, and the maximum eccentricity is 5-9 mm(according to the displacement size), the variable stroke is very short. Thevariable mechanism is designed as high pressure control and controlled bycontrol valve. Therefore, the pump response speed is fast. The design of radialstructure overcomes the problem of partial grinding of sliding boots such asaxial plunger pump. Make its impact resistance greatly improved.

Hydraulic press

Hydraulic plunger pump by air pressure oilsupply hydraulic tank, after each start of the machine, must wait for thehydraulic tank to reach the use of air pressure. Straight shaft inclined disc plungerpump is divided into two types: pressure oil supply type self-priming oiltype.   The pressure oil supply typehydraulic pump mostly adopts the pressure oil tank, also has the hydraulic pumpitself to supply the pressure oil to the hydraulic pump inlet. The self-primingability of self-priming hydraulic pump is very strong, no external force isneeded to supply oil.