Progressing cavity pumps for explosion emulsions
This falls into one of the more interesting applications we see - pumping of ammonium nitrate. We commonly see these applications in the mining market. Progressing cavity pumps are the pump of choice here because of the low shear that they apply on the product as well as the high viscosity of the explosive liquid.
Why is the right design important or what are some of the hazards users might experience when pumping ammonium nitrate?
- Deadhead pumping which is caused by cooled down emulsion explosive forming a plug or by a foreign object
- Dry pumping which generates excessive heat and may result in ignition of explosive residue
These are just some of the reasons the Allweiler branded pumps are the pump of choice. Allweiler pumps applied in this application are intrinsically safe and have met (or can meet) the necessary hazard operation reviews required.
Download your copy of our progressing cavity pump brochure, fill out the application data sheet and get the right pump for your application or contact us to learn how we can help.
Sean McCandless Industrial Market Manager Colfax Fluid Handling
Uh oh…my pump didn’t last as long as I think it should
The next section on our series on diagnosing or understanding pump problems, will focus on rapid pump wear.
Rapid pump wear is caused by either abrasives in the liquid or operation under conditions for which the pump is not suitable, such as excessively low viscosity or excessively higher pressure or temperature. If abrasives are a normal condition of the pumping application, as in slurry pumping, then pump wear will be a fact of life, and the best that can be done will include pump and drive speed selection that provides the best economic evaluation over the pump life cycle. While requiring bigger displacement and more expensive pumps, slower operation on abrasive service often pays back far beyond the initial purchase cost differential.
Wear due to abrasives in the liquid is a function of speed raise to a power usually betwen 2 and 3. If the abrasives are deliberately introduced, as when fuel oil additives intended to reduce boiler corrosion are brought into a system, they should be injected downstream of any liquid recirculation to insure that they do not go through the pump. Obviously, if abrasive foreign material is not supposed to be present, strainers or filters should be employed wherever possible and practical.
Rapid wear is sometimes not wear in the sense of a non-durable pump, but rather a catastrophic pump failure that occurs very quickly. Looking at the pump internal parts alone can frequently not provide much help in setting a direction to search. So, it is important to know what was occurring in the time period immediately preceding the detection problem.
Often, pump manufacturers offer a checklist designed to help you understand potential causes to failure. Contact your supplier today to discuss your issue and what supporting information they have available.
I'm also pleased to announce that our IMO pump brand has an updated Application Data Sheet. The data included in the online tool enables our engineers to answer your questions and projects request quickly and accurately. Moreover, you can consider products from the entire Colfax product portfolio.
Sean McCandless Industrial Market Manager Colfax Fluid HandlingThoughts and Comments from the Power Gen Show in Las Vegas
The Colfax Fluid Handling team was on display at the Power Gen show in Las Vegas. If you attended the show, hopefully you had a chance to come by and say hello. Overall, I thought the show attendance was greater than the 2009 Las Vegas show, but less than the 2010 show in Orlando.
The quality of leads generated at the show was, however, solid and the Colfax team was fortunate to talk with people who -
- Had problems with water in their lubrication Oil (recommend the ThermoJet or PurLube)
- Was interested in pumping sulfuric acid within the environmental system of his plant (recommended the Zenith metering pump)
- Was interested in using a progressing cavity pump in a vertical configuration to save space in his sump (recommended the Allweiler branded progressing cavity or Emtec pump)
- Needed to understand how to size three screw pumps for a fuel oil plant that they were building in the Middle East (recommended the IMO or Allweiler branded three screw pump)
These were only some of the applications that we discussed with show attendees. These leads also show the diversity and flexibility of the Colfax portfolio and the global coverage that we offer our customers.
Finally, we always welcome the opportunity to conduct a lunch and learn seminar for your associates. We offer topics such as the basics of centrifugal vs. positive displacement pumps, design and considerations for lubrication oil systems and three and two screw pumps benefits and design considerations. If you're interested, let me know.
Sean McCandless Industrial Market Manager Colfax Fluid Handling5 Questions – Designing Lubrication Oil Systems for Power Generation Plants
We are fortunate to work with a great team from Baric who provide us with deep expertise in engineered system construction for the Power Generation, Oil and Gas and Industrial markets. I recently conducted a 5 question interview session with Darren Godsmark, Sales Director. This interview provides a good overview of how Colfax is challenging OEMs to think about their system designs and consider alternatives in system construction and configuration -
Contact us if you're interested in designing a better system.
Baric is well known as a designer and manufacturer of unique packaged units for the rotating machinery industry. The Power Gen industry, however, primarily uses pre-engineered or “build to print” packages. Can you provide some example of your ability to showcase Baric’s design skills in the Power Gen market?
Yes, there are several examples. In fact, we have a design contract to design a skid package for a particular sized turbine for a major global Power Gen supplier.
One of our best examples, however, was a project in which we provided Lube Oil Systems (LOS) for 50Hz and 60Hz turbo-gen sets. It was essentially a “build to print” contract, but we identified a number of improvements that could be made on the systems, which we relayed to the customer.
We’re quite proud of our ability to add value to a customer’s projects by drawing on experience and know-how.
Was the customer interest in finding out about the improvements?
Absolutely. We were invited to participate in a number of seminars – mini-Kaizens, actually, with their design team.
What was the focus of the seminars?
There were essentially three considerations:
- Review and update the global specifications for the lubrication oil system
- A detailed review of main sub-supplied equipment, such as pumps, motors and control valves
- The physical layout of the lubrication oil system
What were the biggest challenges the seminars presented?
The first two were fairly straightforward as the assembled teams worked through the original global specifications. We discussed each element in detail – from material selections of reservoirs and piping to potential suppliers for the main buy outs. We then created a revised final version based on a combination of best practices, shared field experiences and sub-supplier evaluation.
The real challenge came in the design of the LOS itself. Both the 50Hz and 60Hz Turbo-Gen sets had to have the same physical footprint. Site interface points had to be located in the same places. Multiple Lube Oil Cooler options had to be designed without changing the footprint. This included the remote air cooled heat exchanger, plus a single plate & frame water cooled heat exchanger LOS and a dual (duty and standby) plate & frame water cooled heat exchanger, both mounted on the LOS. Both required European (CE) and North American instrumentation installation, as well as AC and DC motor installation. Working together, the customer’s team and the Baric team were able to solve these issues.
Do you think the exercise was a success?
Most definitely. By achieving the design brief as describe above, it gave the customer the option to provide the LOS as a stock order item, based on local requirements, for any area of the world in which they marketed. But for us, the biggest validation was the number of contracts we received by using this design, supplying machinery in Asia, the Americas and Europe.
Sean McCandless Industrial Market Manager Colfax Fluid HandlingExcessive Noise or Vibration
In our continuing series on diagnosing pump problems, we're going to tackle the problem of excessive noise or vibration.
Excessive noise and/or vibration is typically a symptom of cavitation, suction starvation or excessive gas in the liquid. This is especially true if the discharge pressure is fluctuating or pulsating. Mechanical causes of noise and vibration include shaft misalignment, loose couplings, loose pump and /or driver mounting hardware, and worn or damaged driver or pump bearings.
Also, pump valves can also vibrate noisily. Especially on the discharge side of the pump, valves can sometimes go into a hydraulic vibration mode caused by operating pressure, flow rate and the valve design. Resetting or a change in an internal valve component is usually sufficient to solve the problem, but we recommend that you consult your valve supplier to determine the best course of action.
Check out the Colfax SMART Sense Pulse for a quick, efficient monitoring device for your screw or rotary pump system(s).
Sean McCandless Industrial Market Manager Colfax Fluid HandlingIntroducing the new Zenith Metering Pump Website
If you have the opportunity, we invite you to check out the updated Zenith website. Our goal was to provide users with information regarding the performance of Zenith branded metering pumps and systems as well as detailed information on market applications. Site visitors will also be able to learn about metering pumps and find answers to common questions in the knowledge center.
If you are able to visit, let us know what you think. We look forward to hearing from you.
Antonio Mendoza Product Specialist Colfax Fluid Handling
What to do about excessive power usage
In our continuing series on Rotary Pump Troubleshooting, we'll take a look at the condition of "Excessive Power Usage". As always, consult the factory or your local service representative for additional assistance.
Excessive power consumption can be caused by either mechanical or hydraulic problems. For rotary pumps, the pump power requirements are directly proportional to pressure and speed. If either has increased, the required input power will increase. Power required will also increase if the fluid viscosity has increased. This can happen if the liquid has been changed to something new or the liquid operating temperature has been reduced. Some liquids (grease, for example) are shear sensitive and can become more or less viscous with shear (pumping action) as well as undergo permanent viscosity change from shear over time.
Mechanical causes of high power usage include bearing wear out, pumping elements rubbing (a situation that can lead to pump failure), very bad shaft alignments and poor pulley alignments for belt drive arrangements.
Sean McCandless Industrial Market Manager Colfax Fluid HandlingRotary Pump Troubleshooting
The next series of blog posts will focus on what operators can do to reduce the time it takes to develop troubleshooting skills. These comments are related to their rotary positive displacement pump technology.
Trouble shooting rotary pumps in systems is a skills that takes some time to develop. We are often contacted about a 'pump problem' without users providing sufficient consideration to changing system dynamics. In almost any pumping system, the pump is the most vulnerable component. However, engineers and operators should be aware that systems dynamics are more frequently the cause of the problem. 'Pump problems' are usually caused by a system component malfunction, inadequate control of the liquid or a change in operating requirements, which burdens the system or pump with conditions in which it cannot perform. Today's post will focus on flow loss or low flow conditions. In future posts will talk about loss of suction and low discharge pressure.
In a positive displacement pump, flow loss is normally accompanied by a reduction in system pressure. Either the pump is delivering less flow, or the system is bypassing it - such as through a defective or worn relief valve or pressure control valve. The pump could be worn and internally bypassing (slipping) flow so that less flow reaches the system. In that event, pump repair will be necessary. A partial inspection of the pump internals will usually provide a good indication of wear condition. Also, if the operating viscosity of the liquid has been reduced (new liquid or higher operating temperature), a rotary pump's rated flow will be slightly reduced and even more so for higher pressure operation.
Sean McCandless Industrial Market Manager Power Generation and Industrial Markets
What’s a Screw Pump?
One of the most common questions we here is, "What is a screw pump?". Unfortunately, screw pump is often a generic term that groups a one, two and three screw pump into one category. Each 'screw pump' operates on the same basic principal of a screw turning to isolate fluid and convey it. However, the mechanical design of each is different. The primary difference in one, two three or multiple screw pumps is the method in which the rotor/pumping element is supported within the casing. 'Screw pump' configurations may include single screw/eccentric screw/progressive cavity, external bearing, timed twin screw pumps, small three screw pumps on lube oil services/machinery support services, large crude oil transfer pumps or even Archimedes-style flood control pumps.
Care to learn more screw pumps? This white paper provides information on when a one, two or three screw pump should be used.
Submitted by: Sean McCandless
Industrial Marketing Manager
BioMass and Process Technology
Colfax Fluid Handling published an article in BioMass Products and Technology entitled, "Choosing a pump". Here are a few excerpts:
"When evaluating pumps for biomass applications, we recommend approaching pump selection from a holistic viewpoint. Several different types of pumps, including positive displacement and centrifugal, can be used in the process as the materials are broken down and converted. Ideally, a pump supplier should be chosen on its ability to offer products that match the specification requirements, as well as knowledge of how the pump interacts with the system and materials."
"The physical properties of the material and aggressiveness through the system also have a significant impact on the pump. Pump materials and coatings, shaft seals and the operating point should be specifically adapted to the pump and system. Be sure to communicate the material and system properties to potential pump suppliers."
We look forward to your comments and hope you enjoy the article!