There are many common problems faced by pump operators. These frustrating issues include leaks, cavitation, solids handling and dry run, just to name a few. As pump operators, sometimes we just fall into a habit of accepting these challenges and doing whatever it takes to make the best of a less-than-ideal situation.
Challenges in Chemical Processing Applications
These common problems are amplified even more in chemical processing applications. Most of these chemicals are hazardous to humans and the environment. Leaks are extremely detrimental and must be avoided at all costs. At the same time, the chemicals can be caustic and abrasive, which wears down seals and leads to cracks, breaks or crystallization on the seal faces that result in costly leaks.
The invention of seal-less pump designs aimed at solving these types of pump operating challenges. The technology has evolved greatly over the past two decades and leaks have become less of a concern thanks to these seal-less pumps. Yet, there are still problems that operators are worried about that not all seal-less pumps can overcome. In most chemical processing plants, centrifugal pumps and gear pumps are still the most popular types of pumps utilized. They are most familiar to the engineers and they are often selected by default because they aren’t comfortable trying something different.
Problems with Centrifugal and Positive Displacement Pumps
Unfortunately, centrifugal and gear pumps still present some common challenges in chemical processing applications. Even if leaks are prevented with seal-less technology, the other issues may not be. Here are some failures we regularly see at DXP Pacific:
Dry Run—This is when the pump operates without any liquid. When this happens in a seal-less pump, the results can be catastrophic. Internal components can be damaged significantly when dry run occurs.
Solids Handling—Most chemicals will contain some amounts of suspended particulates or solids that generally come from the process or supply tanks. As the solids-bearing chemicals travel through the pump, they rub against the pump’s casing and other internal components. This leads to increased wear and can also cause clogs, as well, if the solids build up enough in the system.
Cavitation—Every pump consumes NPSH (net positive suction head). Pump systems are designed to handle only so much NPSH. If they consume more NPSH than they can process, vapor forms inside the pump and leads to cavitation. This is a violent implosion of the vapor bubbles and can severely damage equipment.
Operating Range Inflexibility—Most centrifugal pumps are built to operate at a single specified design point (the best efficiency point or BEP). When a centrifugal pump operates beyond its BEP, it will lead to performance problems and potentially internal damage. This means centrifugal pumps have a very inflexible and limited operating range that isn’t ideal for chemical process.
Blackmer MAGNES Series Sliding Vane Pump
The solution to these problems can be switching to a sliding vane pump—more specifically, a MAGNES Series Sliding Vane Pump from Blackmer. These pumps are specially designed for chemical process and prevent the common operational problems presented by standard centrifugal pumps or gear pumps. MAGNES sliding vane pumps feature magnetic drive systems and seal-less technology. They ensure volumetric consistency as a number of self-adjusting vanes slide in and out of the pump rotor.
Here are some of the advantages of a Blackmer MAGNES Series Sliding Vane Pump:
• Seal-less Technology
• Indefinite Dry-Run Capability
• Leak-Free Operation
• Cavitation and Vapor Mixtures Handling
• Solids and Abrasive Media Handling
• Low to Zero Required NPSH
• Self-Priming Operation
• Full-Curve BEP Capability
• Product Recovery
To learn more about Blackmer MAGNES Series Sliding Vane Pumps or other sliding vane pumps designed for better chemical processing, contact DXP Pacific today.