Piston-Pump.pptx
- 1. PISTON PUMP
- 2. • A piston pump is a type of reciprocating pump that moves and pressurizes fluid by using one or more reciprocating pistons; it is typically driven by an electric motor through a crankshaft and connecting rod. • Though there are many types, all piston pumps feature at least one piston moving in an enclosed cylinder. The piston will normally have one or more O-rings on its periphery, which seals against the cylinder as the piston moves. The piston draws liquid into the cylinder and pushes it out under pressure as the volume in the cylinder gets progressively larger and then smaller as the piston reciprocates.
- 4. Swash Plate • The amount of fluid pumped is dictated by the swash plate angle/pitch. Changing the pitch of the swash plate, changes the stroke of each piston, which changes the amount of fluid drawn into each cylinder, and consequently the amount of fluid pumped. Moving the swash plate to a neutral pitch will result in no fluid being pumped (because the length of each piston stroke is effectively zero). It is possible to reverse the direction of the fluid being pumped by changing the angle of the swash plate.
- 5. Cylinder Block • The cylinder block consists of a round cylinder with smaller bored cylinders penetrating through its entire length. Each of the smaller bored cylinders provides the necessary space for the pistons to move linearly back and forth (reciprocating motion). As the pistons move, they charge and discharge the cylinder space. The cylinder volume charged and discharged per stroke depends upon the length of each piston’s stroke.
- 6. Port Plate • Fluid is drawn into the cylinders, and discharged from the cylinders, via the port plate (sometimes called the ‘valve plate’). Inlet/Outlet • Fluid enters or exits the pump through this port. The swash plate dictates in which direction the fluid will flow through the pump i.e. if the port is an inlet or outlet port. Drive Shaft • The power to rotate the pump is provided via the drive shaft. Piston pumps are usually electrically or mechanically driven, although it is also possible to hydraulically operate the pump.
- 7. Positive Displacement Pump Positive displacement pumps are self priming pumps and are normally used as priming devices. • They consist of one or more chamber, depending upon the construction, and the chambers are alternatively filled and emptied. • The positive displacement pumps are normally used where the discharge rate is small to medium. • They are popularly used where the viscosity of the fluid is high. • They are generally used to produce high pressure in the pumping system.
- 8. Dynamic Pressure or Roto-Dynamic Pump • In dynamic pressure pump, during pumping action, tangential force is imparted which accelerates the fluid normally by rotation of impeller. • Some systems which contain dynamic pump may require positive displacement pump for priming. • They are normally used for moderate to high discharge rate. • The pressure differential range for this type of pumps is in a range of low to moderate. • They are popularly used in a system where low viscosity fluids are used.
- 9. Positive Displacement pump: • Reciprocating Pump • Screw pump • Gear pump • Piston pump • Ram type pump • Vane pump
- 10. Dynamic Pressure Pumps: • Centrifugal pumps • Axial flow pumps • Submersible pump • Centrifugal-axial (mixed) pump.
- 11. Advantages of a Piston Pump
- 12. • With an enormous, wide pressure range, piston pumps are able to reach incredibly high pressures that can be controlled without any impact on the rate of flow. They’re incredibly clever pieces of kit, and have many uses and advantages. • As well as the above, they also have a continuous rate of discharge meaning they can move viscous fluids, high gas volumes and even solids throughout machinery. So a major advantage of a piston pump is efficiency, as well as how useful they are and how they can move fluids through a machine, regardless of viscosity.
- 13. • If they’re properly maintained, it also means they have a long performance life and will serve you well throughout. • Piston pumps are vital for many businesses and are an incredible feat of engineering, having been used for a long period of time within certain industries. The major benefit of them is therefore how useful they are to operations, often proving vital when used.
- 14. Disadvantages of a Piston Pump
- 15. • Cost is a major disadvantage of a piston pump, as they can be expensive affairs up-front. They pay for themselves in the long-run, but the initial cost may seem a little eye-watering due to the size and complexity of the machinery. • Another major disadvantage comes down to maintenance yet again, as if not properly lubricated, the mechanical parts within a piston pump are prone to wear due to the high pressure they are placed under and the psi they generate.
- 16. • They are also incredibly heavy due to the nature of the components used, and are also very large. Valves must be kept intact with piston pumps, and must be resistant to abrasives for larger, thicker liquids or solids to pass through. • This leads us back to the issue of maintenance and lubrication being of vital importance. Such complex pieces of engineering require great filtering accuracy and regular maintenance to ensure the unit remains fully operational at all times, so it’s hugely important they are well- lubricated and maintained throughout their lives.