Hitemp 150 allows for superior cantilever pump support bearing design
High temperature bearing material Hitemp 150 has solved casing and impeller wear problems on a cantilever sump pump pumping dirty water at 90° (194°F).
| Pump type | Vertical Spindle Cantilever |
| Shaft size | 75 mm (3") |
| Rotational speed | 1450 RPM |
| Pumped medium | Dirty, hot water |
| The original design of the pump did not
support the shaft below the base plate. Due to the long length of the pump,
the shaft was unstable resulting in excessive casing and impeller wear. The
pump was operating in a sump with dirty water at an operating temperature of
90°C (194°F). The end user required the shaft to be lengthened. It was proposed to install support bearings both at the shaft midpoint and close the impeller. Vesconite standard had been used successfully in the past for the carrier bearing at the wet end of the pump, but Vesconite is not well suited to bearing applications at these elevated temperatures for long periods of time. The bottom impeller support bearing is immersed in the pumped medium and therefore sees the high temperatures and the high abrasive conditions of the pumped medium. |
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| Cantilever pump design before modifications |
Because of the high temperature, it was decided to specify Hitemp150 which is a high temperature material with a low friction and good abrasion resistance. The bearings were split and mechanically secured to ensure that the thermal expansion of the material would not result in shaft seizure.
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Hitemp 150 installed as impeller support bearing |
The intermediate support bearing does not have a reliable lubrication system, and therefore should be self lubricating in order to overcome temporary suspension of the lubrication. Hitemp 150 with its internal lubricants was specified here as well.
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To overcome the lubrication problem, the intermediate bearing was lubricated
from the discharge pipe with unfiltered process water. The pump was installed and operated for more than three times as long as the life of the previous design without any problems. Hitemp 150 is a unique bearing material. The high temperature rating, relatively low friction and good abrasion resistance make this the material of choice when operating temperatures are high or where the pumped medium is dirty or particularly abrasive. Hitemp 150 bearings can be lubricated with a wide range of process fluids. This minimizes the need for cumbersome and unreliable lubrication lines as well as eliminating the environmental hazard of grease in process water. |
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Pump after assembly |
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Old worn impeller and casing |
Updated Apr 30 2002
