How an aftermarket pump rebuilder joined a California county to engineer a cost-effective upgrade.
by Robby Byrom & Gary Dyson
August 29, 2018

Many factors, including design and terrain, affect the efficiency and lifespan of any pumping system.

For the West Coast of the United States, most residents face issues from catastrophic heat waves and droughts that plague one of the region’s biggest industries: agriculture.

It is said that California accounts for almost half of the country’s fresh produce and crops, with approximately 50 billion in products per year through the state and another 50 billion in ancillary products, according to the Orange County Register and The Washington Post. California clearly depends on agriculture, which means the risks and consequences that come with being in a semi-arid desert environment only grow greater.

The precision engineering and hand machining of this vane is a work in progressImage 1. The precision engineering and hand machining of this vane is a work in progress. (Images courtesy of Hydro, Inc.)

When Water Is Scarce

Farmland is decimated at every turn. Fruit groves turn into dry, brittle wood piles while farmers abandon their land as once fertile soil becomes acres of desert. In cities, the fear of biohazards inch ever closer with the water supply dwindling. Public service announcements encouraged citizens daily to work harder to conserve.

Still, about 30 dams and reservoirs have been emptied or drained, reaching almost 100 billion gallons of water lost, per Add in the additional losses to economic movement from wasted potential labor, livelihood and the estimated losses in the industry at minimum is within hundreds of millions, with the predicted worst-case scenario one in the billions, says the Los Angeles Times.

Though occasional rainfall helps, the state is still lacking water resources. State officials estimate that 80 percent of all water resources are used for agriculture, per The Washington Post. So, groundwater inevitably plays an important role. Devising ways to bring water to the community from rivers, valleys and reservoirs becomes tantamount to survival.

Agricultural pumps are also seldom considered as one of the main runners of the pump industry. California’s industry means that counties’ pumps posed a special exception to the norm when it came to management, repair and replacement.

A finished axial propeller and cone.Image 2. A finished axial propeller and cone.

How the Pumps Failed

In fact, a major county in central California found itself in a crisis when its irrigation pumps were not even producing a foot of head, cutting off the critical water supply to the reservoirs and aqueducts. During this time, the county had to borrow water from the adjacent municipality. Between high vibrations during startups, metal on metal grinding and repeated failures, the entire pumping station was down.

The county reached out to the original equipment manufacturer (OEM) who extended their abilities as far as they could. However, the station operators noticed the same problems occurring repeatedly. A county inspector who had a strong background in pump engineering, Kent Kreeger, came out to inspect the issue. After a thorough inspection, he decided the pumps needed a full engineering study.

One aftermarket pump rebuilder has experience with similar issues previously and was able to analyze, deduce and quickly find a working solution. Knowing how critical the role would be, a field service team was mobilized with the full knowledge that time was of the essence, but quality and a meticulous analysis was to be the forefront of their work. The team soon realized after careful consideration and strict observation of how the pumps and the system worked that the issues started from one end, only to result in almost catastrophic effects on the others.

Vibrations, Systems & the Damage

Vibration is considered to be one of the main factors that play a role in how pump efficiency works. Depending on the frequency of the vibration and how it works in tandem with other factors (which may include pump design, environment of the system itself, the metal used, etc.), it is common for end users to see a decline in efficiency and reliability of the pump. It is also likely that end users see an increase in costs due to repairs and energy needed to continue wielding problems. As such, vibration is one of the many banes of the pump industry.

The county in California was one of the many whose pumps fell into the category of needing repair due to vibration issues. An aftermarket pump rebuilder’s analysis and study of the pumps showed that there was a great amount of vibration that led to overall damage.
The bearings were destroyed during operation, which severely damaged the shaft, bushings, vanes and propellers—meaning that the county’s longest lasting pump ran only to about 1,400 hours.

The components had been severely damaged due to friction. There was an alarming clearance of 1 inch between the propeller’s vanes and the column interior.

In addition, engineers found the rotor parts were “whipping” due to deflection at its own internal pressure, which was off center. The overhung rotor had resonance with the running speed, causing the additional damage.

All of these issues affected one another, from the damage to the pump’s parts to the sediments gathering at the nose from faulty protection to create the issues in efficiency.