Function And Operating Principle; General Precautions - Johnson Pump SPX MDR Manual De Instrucciones

MDR
1.6
1.7
MDR/EN (1206) 3.2

Function and operating principle

The drive magnet, attached to the drive shaft transfers its torque to the impeller magnet.
The impeller can thereby rotate around the ceramic shaft in the pump body without any
physical contact between the drive shaft and the pump body. This makes the pump
completely leak-proof.
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Figure 1: Function and operating principle.

General precautions

• Do not run dry. If the pump is run without liquid, friction heat will be generated inside
the pump which will melt the impeller onto the ceramic shaft and also possibly cause
damage to other parts.
• Do not use the pump for other liquids than quoted for without consulting your SPX
distributor.
• Do not run against closed valve. The pump will be damaged if it is run more than 3
minutes against closed valve.
• Do not run reverse. The impeller must rotate in clockwise direction when viewed from
the motor end (see rotation arrrow on the pump body).
• Do not run with cavitation or air entrainment.
• Do not run with fluid containing solid or abrasive particles without consulting your
local distributor.
• Do not expose the pump to thermal chocks.
• Check the impeller bearing, shaft and wear plates regularly for wear (see paragraph
3.4 "Routine control").
• Do not cause chock pressure.
• Check motor specifications for start-stop frequency.
• Flawed maintenance will result in shorter lifespan, possible break down and in any
event loss of warranty.
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Introduction
1. Ceramic shaft
2. Impeller
3. Impeller magnet
4. Drive magnet
5. Magnet housing
6 Drive shaft
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