Put a Good Base Under Your Pumps

We know that a solid foundation is a proven way to increase the mean time between planned maintenance for most types of rotating equipment. But not all rotating-equipment bases are created equal. As reliability expert Heinz Bloch notes in his 2011 book Pump Wisdom, there is no single, accepted way to mount rotating equipment, such as pumps. These units can be mounted in many different ways, some of which are OK to be done “at least cost,” writes Bloch, just as “there are times and places to do it with uncompromisingly high quality.”

Bloch continues that “even a superb pump design will give poor results if poorly installed. A moderately good pump design, properly installed, will give good results.” For Bloch, proper installation means a good foundation in addition to good shaft alignment and the absence of pipe strain. He stresses that “no pump manufacturer designs its pumps strong enough to act as a solid anchoring point for incorrectly supported piping, or piping that causes casings and pump nozzles to yield and deflect.” Also, pumps must be “properly secured to their respective base plates,” he writes, “and these base plates have to be well-bonded to the underlying foundation.”

Industry has long depended on cast or fabricated metal for equipment base materials. Today, polymer concrete, introduced to building trades in the 1960s, is emerging as a popular alternative to traditional materials, and offers several benefits. Often referred to as a poly, granite, or mineral cast baseplate, polymer concrete combines well‐defined, grain-sized aggregates with a thermoset epoxy or vinyl ester resin. According to its manufacturers, polymer concrete can be cast to precision tolerances while offering the mechanical properties suitable for most industrial applications. Scott Sapita, co-founder and managing partner of BaseTek, LLC (basetek.com), a Middlefield, OH-based maker of polymer concrete bases, offered the following specific benefits.

This ITT Goulds pump is mounted on a polymer concrete baseplate from BaseTek.

—Rick Carter, Executive Editor

Vibration damping: The polymeric matrix of polymer concrete provides damping ratios greater than steel or cast-iron. Polymer bases can effectively minimize vibrations without the need to increase mass size of the component.

Precision mounting: Cast mounting surfaces of most polymer-concrete formulations are typically flat within 0.002 in./ft., which reduces soft-foot and speeds alignment. Also, polymer thermal expansion rates are less than those of cast iron, and the material maintains consistent alignment in a wide range of operating conditions.

Corrosion resistance: Advanced resin systems offer protection from many fluids that may otherwise require an expensive alloy or possibly corrode cast iron or steel. Polymer-concrete systems eliminate the need for additional protective coatings or periodic upkeep and maintenance activities.

Faster installation: Polymer-concrete baseplates will not twist, bend or diaphragm. This eliminates the need for field adjustment during installation. Most designs also incorporate threaded leveling inserts along with a bottom surface ready for adhesion to grouting material without modification or special preparation.

Other benefits: Polymer-concrete materials offer low levels of heat conduction, act as an electrical insulator, are non-magnetic, and resist water absorption. Their mechanical properties are suitable for most indoor-outdoor environments found in the process industries.

To learn more about the specification, design, and installation of sound rotating-equipment bases and the benefits polymer concrete models offer, visit basetek.com.