The ability to provide technical and market details is vital to suppliers of the irrigation pump market.
By Mike Allen
Irrigating Our Future is a new column by Mike Allen. He was employed at Western Land Roller/Ingersoll Rand/Ingersoll Dresser, now Flowserve, for 30 years. He began his career in Hastings, Nebraska, in product engineering, transitioned into engineered sales in Fresno, California, and spent the last 20 years as the sales and marketing manager for Groundwater Development for North America. His column will focus on all aspects of the irrigation segment of the groundwater industry.
I thought “No problem” when asked to consider writing a column on vertical turbine pumps in the agricultural market.
The linkage is obvious with agriculture using more than 90% of groundwater pumped, and a vertical turbine pump—configured as either line shaft driven or submersible—being the primary mechanical device to access it.
Sure, I wondered: “What topics haven’t already been covered multiple times across a number of venues and formats?”
However, I believe an ongoing discussion on teaching and disseminating information cannot be understated and is as important as the technical knowledge itself. That opinion is based on my 30 years of experience in the industry and the progress I’ve witnessed.
Changes to the centrifugal pump itself have been primarily limited to construction materials and to manufacturing processes. The physical properties of converting mechanical energy into hydraulic energy in a centrifugal pump have remained unchanged—and that could be a future column unto itself.
The same cannot be said, though, of the technology surrounding the tools with which we design, apply, and communicate our pump solutions to contractors and end users. We have all witnessed and participate in the tremendous advancements in information technology.
When I first transitioned from product engineering into engineered sales 27 years ago, my tools were a 3-inch-thick catalog and a calculator, while my communications took place in phone booths. Today, we carry on our hips access to almost limitless data via smartphones. This includes everything from customer databases and contact details to technical information including powerful pump application software.
As I reflect on the valuable gains in efficiency this technology has brought, I’m also aware of the casualties that can and do occur as a result. Markedly, there is the challenge of passing on the importance of building relationships through interpersonal communication. Note, I am not talking about email or texting here. Cliché or not, it really is true: People buy from people.
A strong interpersonal communication skill will certainly be a developmental opportunity for the next generation of industry professionals who currently may be more adept at communicating with their thumbs than with eye contact and a firm handshake.
As important as interpersonal skills are, that is not the topic I want to dive into here. As a professional’s time becomes ever more valuable, we must use the often brief course of our interactions to establish ourselves as a necessary resource.
This resource position can take on many forms. Given personal experience in the manufacture and application of vertical turbine pumps, my role is generally viewed as that of a technical resource. However, it would be a lost opportunity to define the role so narrowly.
Many of the water well professionals I encounter, and you surely do too, are leaders of family businesses spanning several generations. These folks have awesome expertise within the scope of their operations and specific market areas.
But there have been occasions for me where my own experience provided valuable insights into topics these water well business professionals may not have been exposed to. Subjects such as succession planning, safety programs, personnel issues, and impending water legislation are just some I’ve discussed through the years.
Indeed the risk to some small businesses may be while they are exceptional water well drillers and pump installers, they may be lacking in some broader business disciplines that would ensure their continued growth and transition to the next generation. These are important opportunities to build value into a relationship beyond just a supplier-purchaser setting.
From the perspective as a technical resource, the role has changed in two primary areas over the course of my career.
First, internally as a manufacturer, it is our responsibility to train the next generation of application and product engineers in the mechanical and hydraulic fundamentals of centrifugal pumps.
You may say this has always been the case, and you would be correct. Nonetheless, a tendency within the industry is to streamline training to simply the keystrokes of our application software and electronic systems. In an environment of limited human resources, the pressure to bring new engineering hires online more quickly is obvious.
Capitalizing on the efficiency these electronic tools bring is important, but by no means comprehensive. What is needed is investing the necessary time to teach the methodology of pump applications and problem solving. This includes time spent in the various manufacturing processes as well as time spent in the field with customers, during installation, and field service situations.
Also required is the patience to overcome the reluctance of new technical graduates coming out of school to manually “go the long way around” and fully understand the logic behind the keystrokes.
It is striking to me how differently this next generation is conditioned in learning by growing up with computers. We need to recognize and be sensitive to this.
A Sophisticated Market
Second, the agricultural pump market is more sophisticated today than what it was years ago. Energy costs and rebates on pumping plant efficiency improvements dictate maximizing efficiency is a priority now more than ever.
Variable speed operation is becoming more common as variable frequency drive technology gets more cost competitive. It is not uncommon for multiple pumps to be used to support a single irrigation system or a single pump to support multiple systems.
The systems themselves are also more complex with multiple operating points resulting from corner systems on center pivots and variable rate irrigation (VRI) sprinkler packages.
These additional considerations influence pump selections based on the characteristics of the manufacturer’s published head-capacity curve and the point or points at which they intersect the irrigation system head curve. Regardless of the seeming complexity of some systems, the interaction of the pump curve to the system head curve is relatively easy to understand and highly predictable when the system head is broken down into its components.
Some installation contractors have been successfully applying pumps for years without completely recognizing the interaction of the system head components for which they are accounting. This lack of understanding will make applications more confusing as they get exposed to more complex situations as described above.
The starting point is generally selecting the pump model by choosing a performance curve (head-capacity curve) to optimize the efficiency at the desired system operating point or points. Following the performance curve selection, an accurate calculation of the system head curve is essential to make sure you arrive at the desired operating point (flow) on the head-capacity curve.
The system head curve calculation is comprised of three components:
- Static head: The total lift from the surface of the water (pumping water level) to the delivery point/elevation of the irrigation system
- Pressure head: The system design pressure requirement in feet (psi × 2.31)
- Friction head: The head losses in piping and appurtenances at any given flow rate in the system.
The sum of these three components make up the total system head requirement. Note: These are the head components that are external to the pump. Internal head losses must be added to the final pump design.
If the pump has been selected correctly, the intersection of the pump performance curve (head-capacity curve) will occur with the system head curve at the desired flow rate. It merits stating again: It is the intersection of the head-capacity curve with the system head curve that determines the flow rate. Another way to think about this is to question what does a pump see: head or flow? The answer is pumps see head. This is true at any point within the piping system.
Therefore, when multiple pumps are joined in a distribution system or when multiple systems are supplied by a single pump, the performance of each pump can be accurately predicted by correctly evaluating the system head at the point at which the pump connects to the system.
While the technical issues and responsibilities discussed apply primarily to suppliers and application technicians, the business fundamentals described here are more general in nature. They are principles that provide opportunities for organizations regardless of size and across the spectrum of responsibilities to set themselves apart.
By investing in the next generation of industry professionals, they will be increasing their value proposition to their business partners in an ever more competitive environment.
In my next column, I want to expand on the discussion I began on matching the head-capacity curve to the system head curve, specifically by looking at curve shapes (steepness vs. flatness) and how that can impact pump selection.
Mike Allen has worked extensively on water issues in Nebraska and was appointed by the governor to the Water Well Standards and Contractors Licensing Board in 1999 and served as chairman until 2013. He also served two terms as a director on the Little Blue Natural Resources District Board of Directors and serves on the Board of Directors of the Nebraska Water Resources Association. Allen currently serves on the Board of Trustees for Mary Lanning Memorial Healthcare in Hastings, Nebraska. He can be reached at email@example.com.