Water pump impellers

Example 7.15. A centrifugal water pump impeller rotates at 1800r/min see Fig. 7.17. The water enters the blades at a radius of 1 in and leaves the blades at a radius of 6 in. The total flow rate is 100 gal/min. The tangential velocities in and out may be assumed equal to the tangential velocity of the rotor at those radii. What is the steady-state torque exerted on the rotor ... 

Applications and uses automotive electrical applications, water pump impellers, HVAC equipment, solar heating systems, packaging, and circuit breakers. 

Coolant Systems - extension tubes, heater core tanks, thermostat housings, valve components, water inlets/outlets, water pump impellers. 

A pump impeller and a shaft bushing from a small cooling water pump assembly were generally corroded. Reddish surface discoloration revealed layer-type dezincification (Figs. 13.14 and 13.15). 

The specimen in Fig. 17.15 is part of a cast iron pump impeller. The spongelike surface contours are apparent, as is the black coating that covers surfaces exposed to the cooling water. Microstructural examinations revealed preferential deterioration of the iron matrix surrounding the graphite flakes. 

Impingement by high speed, turbulent water, and particles. Erosion-corrosion of pumps, impellers, and fittings... 

You must purchase a centrifugal pump to circulate cooling water that will deliver 5000 gpm at a pressure of 150 psi. If the pump is driven by an 1800 rpm motor, what should the horsepower and torque rating of the motor be, and how large (diameter) should the pump impeller be, assuming an efficiency of 60% ... 

Under-the-hood components, impellers for water pumps in engine cooling. .. 

Machine housings, pump and filter housings, impellers, fluid and material handling components, water pump housings and impellers in machinery and engineering, impellers, plumbing systems... 

Stainless steel pump impellers are giving excellent service in sea water. The same may be said for stainless steel ship propellers now in use on coastal vessels. In both cases, it is essential that the stainless steel not be left for long periods between runs in stagnant sea water. 

Most martensitic steels are hardened by heat treatment. These steels tempered below 425°C have good corrosion resistance. When the steels are tempered at about 425-540°C, resistance to SCC and hydrogen embrittlement is increased. The corrosion resistance of the steels in potable water and high-purity water at high temperature is satisfactory. These steels are highly resistant to flow erosion and erosion-corrosion. These steels are useful in applications such as boat propellers, propeller shafts and pump impellers. 

Some typical applications of the alloys are in propeller shafts, propellers, pump impeller blades, casings, condenser tubes and heat exchanger tubes. The corrosion rate in flowing seawater is <0.025 mm/yr, but can pit under stagnant water. Alloy 400 is immune to chloride SCC. 

Molten sulfur has a viscosity (-0.01 kg m 1 s 1, 400-420 K, Fig. 3.2) about ten times that of water (-0.001 kg m 1 s 1, 293 K). Its density is 1.8 kg/m3. It is easily moved in steam jacketed steel pipes (Jondle and Hombaker, 2004). Steam heated pumps much like that in Fig. 9.2 are used. Molten sulfur is an excellent lubricant at 410 K. Sulfur pump impellers need no additional lubrication. 

Pump test results on a centrifugal water pump with impeller diameter of 14.62 in. (From R. L. Daugherty and J. B.j Franzini, Fluid Mechanics with Engineering Applications, 6th ed, McGraw-Hill, New York, 1965. Reproduced by permission of the publisher.)... 

Plumbing components fittings, pump impellers, shutoff and mixing valves, valve stems, tees, elbows, couplings, water filter housings, irrigation system parts faucet cartridges, toilet flush valves, ball cocks, showerheads... 

If the water effluent from a cooler is unusually warm but the inlet temperature is about normal, check the pressure on the discharge of the cooling water circulation pump. Low cooling water pressure is sometimes due to deterioration of the cooling water pump s impeller or wear rings (see Chapter 11). A badly fouled screen on the inlet to the pumping sump (see Fig. 16-1) will also reduce the efficiency of the pump. If the level in the pump is more than a few feet below the water level in the basin, the screen should be cleaned. 

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