Beginners Guide

Every industry today requires a pump somewhere in its operation. From food processing to oil wells, pumps play a critical role in the production and maintaining our standard of living. Pipes carry the fluid, but pumps supply the energy to move it. Because the piping and pumps work together, they must be thought of and designed as an integrated system. Change one part, and the system can become less efficient. In this Beginner’s Guide to Pumps, we attempt to keep the Information basic and non-technical as possible. Bear in mind that pumping systems are highly technical in nature. Every length of pipe, elbow, valve, the height of the pump above or below the reservoir, fluid viscosity and inside diameters of all equipment effect the optimal discharge flow for the system. This guide covers the short history of pumps to see how they evolved over time. We then cover the basic parts, Types of Pumps and the industries that use them. Lastly, we include some basic troubleshooting topics. We hope that you find this guide useful. When it comes time to plan for a new pumping system or repair an existing one, you can rely on the
experts at All Pumps to get the job done right the first time… every time.

Another difference between Centrifugal and Positive Displacement pumps is how they discharge their contents. Displacement pumps typically have a pulsating flow or periods when there is no flow whereas rotodynamic pumps have a continuous flow.

Other factors in pump classification include:
• Whether the fluid delivery is constant or variable at a given speed
• Type of application
• Materials from which they are constructed
• Type of fluids or materials they move
• Structural features

虽然从源到管道pump are called “suction lines,” pumps do not “suck” liquid; they push it. The pump creates a vacuum into which the fluid flows forced by atmospheric pressure, the same pressure when using a drinking straw or vacuum cleaner. For example, centrifugal pumps create a low pressure in the eye of the impeller and air pressure pushes the fluid into the pump via the suction line. Now let’s look at each pump type in more detail.

Centrifugal Pumps

Slurry Pumpsare the workhorses of the mining industry. They are robust pumps usually constructed from thick cast iron to withstand abrasive fluids mixed with solids like concrete, mud and other viscous, abrasive materials. The casing has a replaceable rubber coating or lining to protect the metal from damage. The impeller vanes are shorter to allow passage of stones and solids without damaging the system.

Submersible Pumps低于表面的液体泵,泰pically inside tanks or wells. The pump motor is hermetically sealed and close-coupled to the pump end. They have the advantage of being self-priming but can be more problematic to maintain. Submersible pumps are also called stormwater pumps, sewage pumps and septic pumps and effectively used in building services, commercial, domestic, municipal, rural, industrial, and rainwater reuse for subsoil water, stormwater, sewage, grey water, black water, trade waste, rainwater, bore water, chemicals and food waste. They come in a variety of sizes and impeller types depending on the fluid viscosity, type of solids to be processed and pumped.

The Dry pit submersiblepump differs from a typical submersible in that it can run both above and below the level of the fluid. They are designed to de-water areas that only flood occasionally. A conventional submersible would overheat, but dry pit pumps have the motor housing filled with a cooling oil.

Vertical Multi-Stage Pumpsare centrifugal pumps with multiple impellers placed in series on the same shaft in a single casing. The fluid increases in pressure as it leaves each impeller chamber or stage. The more stages the pump has, the higher the discharge pressure.

Vertical Multi-stage pumps require less space for installation. The pump uses only one motor to power multiple stages and is best suited for boosting pressure to any clear liquid. Practical applications include increasing water pressure in buildings, light industrial water supply, washing and cleaning systems, such as car washes, irrigation systems and providing cooling lubricants to machine tooling processes.

Vertical Turbine Pumps主要是为需要高头和压力的农业灌溉中的深井和农业灌溉抽水。该装置由顶部的电动机，下方的放电头以及容纳驱动轴和一个或多个叶轮碗或阶段的一个或多个法兰柱。在吸力端通常有一种过滤器的滤网，以滤除石头和碎屑。

Vertical turbine pumps are used for small, single pump commercial applications as well as large, multipump municipal water supply systems. One disadvantage is the high headroom required for installation and maintenance. The advantage of these pumps is that they have a small footprint, are easily customised and very efficient
for high head, low flow applications.

往复泵使用曲轴连接杆机构，就像在汽车中的发动机上工作的方式一样。它将曲轴的旋转运动转换为活塞的直线或线性运动。

There are three moving parts including the inlet valve, the plunger or piston and the outlet or discharge valve. As the piston retracts, ambient air pressure forces the fluid in through an inlet check valve to fill the vacuum left by the piston.

随着活塞改变周期,关闭压力the inlet check valve, and the outlet check valve opens discharging the fluid. The volume of fluid remains constant with each revolution of the crank, but pump configuration determines pressure and system flow. Pump shaft speeds are relatively low, requiring speed reduction from the motor or driver to the pump shaft.

Diaphragm Pumpsalso, called Membrane Pumps, Diaphragm Pumps use a flexible membrane to create low and high pressure by flexing in and out of a chamber. Check valves direct the flow of liquid in and out of the chamber with each reciprocating cycle of the diaphragm. These pumps work well pumping high viscosity fluids such as sludges and slurries containing solid materials. They can reach discharge pressures up to 1,200 bars.

Duplex Pumpsthe official name of the Duplex Pump is Direct Acting Reciprocating Steam Pump. Invented by Henry R. Worthington in 1840 they are still used today. However, the steam has been replaced with compressed air.

双泵有两个蒸汽和两个水箱s that work in tandem. Compressed air enters the top of the cylinder on one side or the other depending on the motion of the
rocker arm over the intake ports creating constant lateral motion of the pump plunger. This is an efficient arrangement as there are no “dead spots.” With the two cylinders about 1/4 cycle out of synchronization, there is always a piston under pressure during the entire cycle.

The duplex pump is used where a high volume of water is required without the threat of backwash. Backwash could contaminate large freshwater storage tanks and render the system unfit for use. They are commonly used in oil drilling to cool drilling heads as well as to flush out the boring holes. Duplex Pumps also work well for transferring low viscosity fuels like
heating oil.

Multiplex PumpsSimply put, Multiplex pumps are a series of plunger pumps with a common power end and fluid end. The power end contains a crankshaft in a crankcase with connecting rods connected to crossheads instead of pistons to alleviate sideways forces to the piston. The fluid end includes individual plungers, each having different spring loaded intake and discharge check valves.

Multiplex pumps provide higher flow rates at lower pressures due to the load limits on the crankshaft and primarily used in oil field applications.

Regardless of the well pressure, multiplex pumps can move significant amounts of fluid.

Piston and Plunger PumpsBoth Piston and Plunger Pumps work with the linear motion displacing fluid inside of a cylinder. The difference is that the seal on the piston moves with the piston contacting the cylinder wall to create a seal. The plunger on a Plunger pump passes through a stationary seal and will generate higher pressure than piston pumps.

There are two types of piston pumps, Lift and Force. In a lift pump, it takes three strokes to complete the cycle. The first stroke or upstroke of the piston draws water, through a valve, into the lower part of the cylinder. With the second or downstroke, water passes through valves in the piston, filling the upper portion of the cylinder. On the third or upstroke, water discharges from the top part of the cylinder via a spout.

Force pumps need only an upstroke to fill the cylinder and a down stroke to force the fluid out.

齿轮泵旋转齿轮泵至少由一组或两组带有牙齿的旋转齿轮组成。当牙齿分开时，它们会产生部分由流体填充的部分真空。当齿轮继续旋转时，流体被困在套管周围，到泵的放电端口。齿轮泵可以是外部的或内部的。

Internal Gear Pumpshandle low and high viscosity liquids from solvents and fuel oil to asphalt and adhesives. The viscosity range is 1cPs to over 1 million cPs. Moreover, they perform well pumping high-temperature liquids up to 400⁰C because the clearance is adjustable to account for the temperature expansion. The internal gear pump has self-priming capabilities and can even run dry for short periods. These pumps are birotational and are used to load and unload the same tanks. With only two moving parts they are reliable and easy to maintain.