| Larry Bachus
(a.k.a. "The Pump Guy")
Last month, I wrote about a young reliability engineer at a petrochemical plant who is worried he might be transferred, or fired (Flow Control, January, page 36). The engineering VP told him to stop chasing vibrations and make the vibrations disappear. (To be perfectly honest, you can’t make vibrations disappear; vibrations can only be minimized to acceptable levels.)
There is a problem. The reliability engineer doesn’t know how to calm the vibrations because he doesn’t understand his pumps. Now balance this with another issue on the other side of the earth.
An engineering supervisor at a global consulting engineering firm in Europe wrote to ask, “What’s wrong with high suction pipe velocity leading to a pump, assuming the NPSH is met?” You might ask, “Shouldn’t an engineer (and supervisor) with a company that designs power plants know about liquid properties, velocity, and flow of water through pipes?
One of these engineers is the reliability team leader in a petrochemical plant. The other engineer is a supervisor in a design engineering firm. How did these engineers rise to their positions? How can they be leaders to mechanics, technicians, operators, and other engineers who clamor for leadership?
Most universities around the globe will graduate a mechanical engineer or chemical engineer in four years. One of the courses in the four-year curriculum is called Fluid Mechanics. Pumps and fluid behavior are covered in this course.
The typical Fluid Mechanics course runs for 13 to 16 weeks, depending on the university. The engineering student sits in the Fluid Mechanics classroom for three hours a week.
Both liquids and gases are fluids. Half the course is dedicated to the study of gas (including air) properties and the way a gas behaves. This is called aerodynamics. The other half of the course is dedicated to liquid properties and the way a liquid behaves in motion. This is called hydrodynamics.
So, the 16-week course only contains eight weeks of dedicated liquid behavior. This doesn’t mean eight weeks at eight hours per day. It means eight weeks at three hours per week. I took Fluid Mechanics in the Spring Semester of 1973. I went to class from 3 p.m. to 4 p.m. on Monday, Wednesday, and Friday. Although that was 40 years ago, the properties of water remain the same.
The professor will dedicate one or two classroom lectures (this means 1 hour, possibly 2 hours) to pumps. What can the professor say about pumps in an hour to students who might never have seen a pump or worked in heavy industry?
The professor talks about the development of pumps through history. The professor says the pump adds energy to a liquid. The professor quantifies the energy as either head (feet) or pressure (PSI) with the math to convert one into the other.
The professor reviews the design parameters (volute and impeller geometry, suction specific speed, NPSH, Affinity Laws, power consumption) important to pumps. The professor explains the difference between a positive-displacement pump and a centrifugal pump because some practicing engineers will have to select one or the other for an application at some point in the future. The professor shows a typical pump curve that contrasts head and flow.
The bell rings. The pump lecture ends. English or History class begins in five minutes in another building.
In the next Fluid Mechanics class, the professor lectures on how and why a vortex might form in the process of draining a tank. The pump lecture assumes its position on the back burner of the student’s mind and slowly fades out of memory.
Most mechanical and process engineering students graduate with a one or 2-hour lecture on pumps in a course called Fluid Mechanics. And this, people, is what most graduate mechanical engineers and process engineers know about their pumps.
I asked engineering professors at three different universities (Tennessee State University, Lipscomb University, and the University of Dayton) the following question:
“In the Mechanical Engineering (ME) curriculum at your university, how many courses of Fluid Mechanics (FM) are required to graduate in four years as a mechanical or chemical engineer?”
One professor said, “All MEs, CivilEs and ChemEs have one required FM course. Fluid Mechanics at our university is purely theoretical. Our MEs will also take a Thermal Fluid Systems Laboratory where they observe and analyze common mechanical engineering systems including pumps.
Another Ph.D. of Engineering (different university) responded, “For MEs, we require one course in FM and another course in Thermodynamics. Pumps are covered in the FM course. Advanced FM is a technical elective. Our CivilE students also take FM with a hydrology lab.”
The third professor (different university) answered, “MEs take one semester of FM. ChemEs take a different FM than MEs. ChemEs also take a course called Heat and Mass Transfer. Civil Engineering students take a different course called Hydraulics, which is mostly open-channel flow and a course on Water Resource Engineering.”
The third professor added an unexpected comment: “Larry, I don’t think the biggest issue is with how many courses of this name are required. Higher education has moved to theoretical BS that is largely an exercise in calculus gymnastics led by a faculty with absolutely no industrial expertise, or even the context of being around mechanical things. Professors without this experience always do what they are best at, namely calculus theory.”
Some graduating engineers will take a position with a company that manufactures a product like an automobile, or piece of furniture. These companies need mechanical and process engineers too. The engineer’s work week will be consumed with welding and assembly robots, assembly lines, and packaging. These engineers might never need the information covered in Fluid Mechanics.
Some graduating engineers will take positions in construction. If the company erects buildings and stadiums, the engineer will liaise with a subcontractor for the internal plumbing pumps and the firewater pumps you might see in a building. He will review some pipe layouts and might have to sign a requisition or pump purchase order.
Maybe the engineer will take a position with the highway department and build bridges and tunnels. For bridges over lakes and rivers, the engineer will need to recall open-channel hydraulics from FM to design and sink caissons in water for bridge supports and design against floods.
However, that one or 2-hour pump lecture in the Fluid Mechanics course is woefully inadequate if the engineer takes a position with a petroleum refiner, municipal water department, mining, power plant, chemical plant, or paper mill.
The third professor said it best. “Higher Education has moved to theoretical BS… led by a faculty with absolutely no industrial expertise, or even the context of being around mechanical things.”
Too many universities are graduating mechanical engineers who can’t build a skateboard and don’t know what happens inside the engine of a car. It’s a problem I observe in many parts of the world.
If there is any interest in converting vibrations into reliable pumps, come to a Pump Guy Seminar this year. We’ll be in Lake Charles, La. and Portland, Ore this year. For more details, visit FlowControlNetwork.com/PumpGuy or call Matt Migliore at 610 828-1711.
The Pump Guy
Larry Bachus, founder of pump services firm Bachus Company Inc., is a regular contributor to Flow Control magazine. He is a pump consultant, lecturer, and inventor based in Nashville, Tenn. Mr. Bachus is a retired member of ASME and lectures in both English and Spanish. He can be reached at email@example.com.