Chemical pumps are used in the petrochemical, food processing and chemical industries, as well as in off-site applications in refineries and high-temperature heating systems. They pump hot, cold, aggressive, volatile, explosive, poisonous, contaminated and especially valuable liquids.
Therefore, parts in contact with the fluid are made of corrosion-resistant metallic and non-metallic materials or are protected by durable rubber, plastic or enamel coatings.
In this pump, the body is coated with plastic to protect it from the corrosive effects of the fluid.
It is possible to use both single and double mechanical seals in chemical pumps. In some cases, a thermosiphon system independent of the pump is used to pressurize the seal area or perform external flushing. As we mentioned above, the fluids pumped by chemical pumps are generally valuable, explosive or harmful to the environment and human health. For this reason, the issue of shaft seal – sealing is very important. If zero leakage is desired, switch to canned motor pump or magnetic coupling pump.
Magnetic coupling pumps are closed to the outside except for the suction and discharge flanges. The shaft provides rotation movement with the magnetic field force. For this reason, it is often preferred in cases where zero leakage is desired.
Chemical pumps are generally designed as single-stage and rarely as two-stage. They are generally not self-priming pumps. For pump selection, it is important that the pump has as low an NPSH value as possible. To meet special operating conditions, design variants with heatable bodies, coolable bearing housings and external systems to support the pump from the outside (thermosyphon system or heating-cooling jacket, etc.) are used.
Source: KSB Global
