Nobody likes a leaky pump and the unscheduled downtime and increased maintenance needs. When these pumps are moving aggressive acids and slurries, they can leak faster and when they do leak they create an unsafe work environment.
Obviously, the biggest contributor to this problem is how quickly mechanical seals in conventional pumps wear out in these kinds of environments.
An often overlooked alternative is the Air Operated Double Diaphragm Pump (AODD). This is because AODD chemical pumps can vary in both quality and effectiveness for this application across the market. However, there are AODD pumps on the market which are ideally suited for pumping hazardous materials.
Why Use an AODD Pump?
AODD pumps use bolts to secure the pump and create their seal – so there is no mechanical seal that will need regular replacement – saving money over electric pumps. As their name suggest plastic pumps can be made of a plastic that doesn’t react with the materials you are pumping – which gives it a longer life compared to other options.
Unlike electric pumps, AODD pumps can run dry and deadhead without the risk of burning, seizing, or harming their components. Finally AODD pumps are gentler than electric pumps – with hazardous materials being fragile – mild turbulence from passing through an electric pump prevents damage to the material.
What Can Cause Leaks In AODD Pumps?
We all know that safety is the number one concern when dealing with hazardous materials. In order to use AODD pumps in your facility to move hazardous materials it’s a good idea to understand the common causes of leakage and how to remedy it.
For moving hazardous materials the most common AODD pumps used are plastic and the most common cause of leakage in a plastic pump is creep and cold flow.
Creep is when a pump deforms (permanently) under load.
Cold flow is when the pump is subjected to continuous loads at a fluctuating temperature – this can cause the different plastic parts to expand and/or contract at different rates which causes deformation of the pump.
Creep occurs over the life of any pump. It is just a more common cause of failure in plastic pumps because they don’t corrode the way metal pumps do. You can expect a good 10 years’ service out of the right AODD plastic pump for your application.
Is it time to replace your hazardous materials pumps?
If your hazardous materials pumps have a corroded pump exterior, leaks around the manifolds, worn internal fluid bowls and discoloration on the floor caused by severe leakage, it might be time to look at replacing that pump. Get in touch with the team at Pye-Barker at 404-363-6000 or drop us a line email@example.com and we can explore your options for replacing that pump.
In December, I shared with you 3 Air Operated Diaphragm Pump (AODD) installation traps. There are another 3 common installation traps that I see maintenance teams make when installing them.
I thought I’d share these with you here to save you the time and hassle of having to wait until something stops working on your AODD pumps to go and troubleshoot it and fix it.
AODD Pump Installation Trap #1: Prime the Pump According To Directions
A lot of plants choose to use AODD pumps when self-priming is required. If you just switch the air flow from off to the required flow rate, you may find that there is not enough time for the fluid to be drawn into the pump to prime it…
This can be avoided by just turning down the compressed air at the regulator for a few seconds – letting the pump work at the reduced pressure – which allows it to draw the fluid into the pump and prime it.
Then you can turn the pump back to full operating speed.
AODD Pump Installation Trap #2: Ensure Your Tubing and Piping Is The Correct Size
The inlet and outlet ports on your pump are selected based on the flow rate you specify. Make sure your inlet and outlet hoses match the pump’s ports.
The main reason is cavitation. Too little flow to the pump and you’ll end up with cavitation which can ruin a pump in no time flat – leading to costly downtime and repairs. Getting the pipes to match the flow rate is worth the fraction of extra investment upfront to avoid the future problems.
Also – I’d recommend using flexible inlet/outlet piping rather than hard plumbing the pump in. As the pump speed increases the vibration increases which elevates the risk of loosening hard plumbed inlets/outlets – creating a risk of leaks forming.
AODD Pump Installation Trap #3: Clear Fluid Line Restrictions During Maintenance.
Honestly, you’d be surprised how often this step gets missed. We get called in on pumps that have broken down and find all sorts of restrictions in the fluid line. We point this out to the client and they mumble something like - “The maintenance team is supposed to look after that.”
If you’ve got a problem with your maintenance team cutting corners, be sure to inspect them – find out who’s doing their job and who isn’t. Also, it’s not hard for a maintenance supervisor to listen for the tell-tale sound of gravel in the pump or flashing around the manifold elbows which indicate cavitation.
Make sure your maintenance team is checking for
Doing your maintenance is like going to the gym for most people… We hate doing it but we feel better afterwards. If you have any questions about your existing air-operated diaphragm pumps then get in touch with our team on 404-363-6000 or drop us a line firstname.lastname@example.org and we can get your questions answered.
We all love Air-operated double-diaphragm pumps (AODD) because they are easy to operate and inexpensive to repair. However there are some installation traps that will see your new AODD pump not living up to its potential.
AODD Pump Installation Trap #1: Not Installing Your Inlet Line To The Specified Size and Pressure
All too often we hear about AODD pump owners who haven’t installed the specified air line. Usually the installed line is too small (thankfully almost nobody installs a line too large).
When the line is too small, the pump doesn’t have enough power to operate at peak efficiency. And we provide pumps that will operate at peak efficiency based on your system’s requirements. So install the pump to the specifications provided…
To insure your pump gets the required air pressure, we’d recommend installing an air regulator between the compressed air supply line and your AODD pump. Too much back-pressure and you can stall the pump. Too little back-pressure and the pump won’t supply the desired flow at the desired pressure.
So if you want peak performance from your pump then you need constant pressure from your compressed air system.
AODD Pump Installation Trap #2: Failure To Inspect Sealing Surfaces for Leakage
The most common forms of leakage in an AODD pump are loss of torque over time. Over time your pump materials will stretch – this in turn can cause your sealing surfaces to loosen – creating leak paths.
Make sure you replace all your polytetrafluoroethylene (PTFE) O-rings during services. Once your PTFE O-Rings have been compressed they don’t spring back to their original shape. Which means the connection is more likely to leak. Which in turn means unnecessary downtime while you fix it.
O-Rings and maintenance technicians are a bargain compared to unscheduled downtime for critical downstream applications.
AODD Pump Installation Trap #3: Forgetting To Inspect For Muffler Icing And Restrictions.
AODD pumps are loud. This is why everyone recommends installing mufflers during installation. As the air passes from the pump to the muffler it is subject to rapid temperature changes – muffler exhaust is often below freezing – which can cause icing in humid environments.
Keep an eye out for erratic pump oration, humid inlet air or frost on the outside of the muffler – these are all signs your pump is not operating at peak efficiency.
If you have these symptoms, you can try these quick fixes:
That wraps up the first three air-operated diaphragm pump disasters. We’ll be back with part 2 soon. If you have any questions about your existing air-operated diaphragm pumps then get in touch with our team on 404-363-6000 or drop us a line email@example.com and we can get your questions answered.
It’s a common problem across a number of industries using Double Diaphragm Pumps to experience vibration on both the intake side and the discharge side of a pump.
These vibrations often result in damage to piping systems and the pumps themselves. Sadly in many industries vibrations and inconsistent flow are often tolerated because of an unwillingness to look for an easily found solution or because of ‘false economics.’
When clients of Pye-Barker look at the price for installing pressure dampeners to prevent vibration in a pumping system or create a desired even output, and then make any sort of comment about price – I often remind them it is really cheap.
Compared to replacing the pump or having to replace your piping system. And really cheap compared to a way to undo mounting fatigue.
Here are four common industries that can drastically reduce waste and maintenance costs as well as, increase productivity by using pulsation dampening in their pumping systems:
Chemical Companies: When pumping products such as surfactants or even volatile chemicals, these substances can aerate leading to foaming or excess vaporization (waste). This can create problems for both storage (requiring longer settling time) and for filling the final containers efficiently (causing overspray, wasted material and rejected product).
Installing the right pulsation dampening system can in many cases eliminate the problem of aeration.
Paper Production: Unloading pumps can experience vibrations and pulsation so strong that it can cause pipe stress, mounting fatigue and even rip the pump from its foundations. Which will obviously lead to unacceptably long downtimes and create a health and safety risk.
Simply installing the correct pulsation dampener on the discharge side of the pumps will reduce mounting fatigue and pipe damage.
Steel Processing: Using plunger pumps in the descaling process can result in erratic flow of the raw material which causes de-scaling to be erratic. For the best results in de-scaling, steel processors need a steady flow of raw material through the de-scaling processor.
Installing the right pulsation dampener on the discharge side of the pump as well as an inlet stabiliser will reduce the vibrations to allow uniform descaling of their raw materials. It also means the entire pumping system no longer violently vibrates. Saving on maintenance and repairs.
Waste Water Processing: When using reciprocating pumps to move waste water – many water treatment operations experience pulsation in on the discharge sides of their pumps. This can cause pipe joints to break and crack discharge pipes.
Pipe damage like this can lead to leaks and easily preventable downtime, which can be prevented with a pulsation dampener solution.
Regardless of what industry you are in and what you are pumping, if your pumping systems are experiencing vibration or water hammer which is damaging pipes, causing downtime or disrupting your operational efficiency; Pye-Barker can supply and install the pump dampening solution for your problems.
Give us a call on 404-363-6000 or drop us a line at firstname.lastname@example.org, we’ll take care if the rest.
One of Pye-Barker’s pump suppliers – ARO was featured on the front cover of ‘Processing’ Magazine.
United DMS (the largest silver-bearing film recycler in the United States) worked through several other unsuccessful alternatives, before using ARO’s pumps and monitoring systems to drive their fluid recovery systems.
They have been so successful in their fluid recovery process that they have been used for their bulk caustic tank and caustic day tank transfer processing areas.
You can check out the full story at http://www.processingmagazine.com/magazine/features/closed-loop-control-in-silver-recycling-2/
We have a customer who does custom chemical mixing for pesticide and herbicide manufacturers. The additives used to produce these products come in both powder and liquid form. Usually the ingredients are mixed with water in large mixing tanks. The product is then moved to a smaller tank that is used as a day tank in filling the customer’s containers. They are usually one gallon and five gallon plastic bottles.
The particular product that was causing problems being mixed had a component that was very light and fluffy. They had tried different methods of moving the ingredient to the mix tank but had problems with dusting and the product would actually foam or bubble out of the top of the mix tank. This was especially true with gravity feed.
The project engineer at the facility relayed these problems to me and I suggested that they try an ARO AOD powder pump. These pumps use regulated aeration ports to keep the product fluidized. The pump also had the optional suction probe which is perfect for moving product from super sacks.
ARO offered a test program for these to insure that the pump will move the product. Our customer found that the material was easily pumped once the proper pump adjustments were made. Since the pump discharge is into a hose it was easy for them to pipe it into the top of the tank. This eliminated their dusting problem and the foaming problem with the gravity fill.
We did these trials several months ago and I recently checked with the customer and they are very happy with the pump.
Many of my customers in north Georgia who produce coatings, printing inks and light weight chemicals and typically use air operated diaphragm pumps are always asking me what we can offer for metering, dosing or being able to remote operate their dispensing operations.
Most of these customers also use positive displacement gear pumps and after learning the initial purchase prices of a variable speed positive displacement with their limited capital budgets are looking for options.
IR ARO recently launched their new Electronic Interface EXP air operated diaphragm pumps that have solenoid control rather than an air valve assembly.
The electronic interface pumps can also be supplied with optional cycle counter to track end of stroke feedback and pump data. The PE electronic interface pumps allow maximum flow rates with minimum air consumption (on average 3%+ less). The PE pumps also have lube free design with fewer parts than the standard pump with the exclusion of the air valve assembly with inclusion of solenoid valve control.
Many of my customers have several AOD pumps in operation for their dispensing requirements that historically needs intensive manpower to operate equipment, and now ARO offers a multi-pump controller that communicates with the new ARO electronic interface pumps which eliminates intensive operating with remote operation and also provides safer control.
Let us schedule a survey of your existing pumps and how they are operated, pending metering or dosing requirements, and discuss how these new improved ARO pump controls can help.
Pump leakage has become more critical in recent years because of environmental concerns, fugitive emissions, handling of carcinogen materials and loss of valuable products. Acid based fluids typically have viscosities similar to water, and may have no or limited lubricity properties. Internal gear pumps or external gear pumps work best with Newtonian type fluids. Shear sensitive fluids are not a good application for gear pumps. The complete list of shear sensitive fluids is endless. Fluids that provide good fluid film between bushings and idler pin have best results with gear pumps. Acid based fluids also may not be compatible due to materials of construction and seals supplied with gear pumps. VIKING Pumps has a stainless liquid vane pump (LVP) for light weight fluids and a non-metallic mag drive external gear pump (CMD) for hazardous fluids that have Newtonian properties and require (leak free) seal-less operation.
As advised above, water based fluids with no lubricity will cause short pump life due to the fluid not providing an adequate film between the bushings and idler pin. Fluids with heavy and large solids will also cause short life for wear to gear pump internals. If fluid suction strainers can be used and if fluid has some lubricity gear pumps will provide positive flow and long life.
Centrifugal pumps with non-clog impellers are typically best pump for high trash fluids.
NPSH (Net Positive Suction Head) is critical for proper operation of any positive displacement pump. Net Positive Suction Head (NPSH) can be defined as two parts:
NPSH Available (NPSHA): The absolute pressure at the suction port of the pump.
NPSH Required (NPSHR): The minimum pressure required at the suction port of the pump to keep the pump from cavitating.
NPSHA is a function of your system and must be calculated, whereas NPSHR is a function of the pump and must be provided by the pump manufacturer. NPSHA MUST be greater than NPSHR for the pump system to operate without cavitating. Put another way, you must have more suction side pressure available than the pump requires.
Please see VIKING Pump website reference document UNDERSTANDING NET POSITIVE SUCTION HEAD for more detailed explanation.
Our inside engineering staff or myself or our other area representatives can assist with proper pump selection and application design.
ARO is launching a series of FDA-compliant diaphragm pumps. The new SD line of FDA-compliant diaphragm pumps is designed to pump and transfer materials for the food, beverage, pharmaceutical and cosmetics industries safely and efficiently.
ARO’s new SD line of FDA-compliant diaphragm pumps yields 20 to 30 percent better flow rates than current market competitors’ and ensures that material is transferred unharmed. Designed to pump and transfer materials for the food, beverage and pharmaceutical industries safely and efficiently, these pumps can be disassembled quickly for easy inspection, cleaning and maintenance.
“We look forward to collaborating with new customers and industries on how the SD line can solve their fluid management challenges,” Wesley said.
A number of advanced features make the SD pump ideal as a feed pump in a filling process, as part of a “clean in place” practice or in a high-volume dispensing application. These include electropolish stainless steel and FDA-compliant materials to pump material while maintaining the integrity of the product, and a proprietary design that prevents leakage and material waste and offers a service life four times better than traditional diaphragm pumps (under normal operating conditions).
The SD pumps build on decades of ARO expertise to provide plant managers and maintenance engineers the best cost-of-ownership rates in the industry.
Call Pye-Barker today for help with your FDA applications!
ARO is launching a new controller with remote operating capabilities. The new ARO Controller delivers on the promise of touch-and-walk-away automation with remote operating capabilities that increase the reliability, productivity and safety of fluid management.
“At ARO we take pride in solving our customers’ most complex fluid handling challenges with straightforward, yet smart solutions that keep their businesses moving,” said Nelson Wesley, global product leader for diaphragm pumps.
This new controller creates a fully automated multi-pump system
The new ARO Controller works seamlessly with ARO EXP Electronic Interface pumps to create a fully automated multi-pump system for batching, container and tank filling and chemical injection systems in a wide variety of applications. The controller can also be integrated with many existing ARO EXP pumps when an electronic interface package is added.
“The remote operating capabilities of the new ARO Controller help manufacturers increase reliability, productivity and safety,” Wesley said.
The multi-pump controller can be programmed with remote triggers customized to the application. The controller responds to those triggers and performs auto-shutdowns when necessary and sends data and service alerts to the operator. The operator is then positioned to make intelligent fluid management decisions to keep business moving.
“ARO is proud to now offer a complete system solution that helps manufacturers and operators manage fluid easily and intelligently, with less operator oversight required,” Wesley added. “Less time standing at the controller means more time on the floor making sure things are running smoothly.”
The new controller improves upon the already precise ARO EXP pump by ensuring the pump is fully primed, resulting in +/- 1 percent repeatability. It features an easy-to-use interface pre-programmed with eight languages and can:
• detect leaks
• operate two pumps simultaneously
• sense and respond to liquid levels
• accurately control proportions
• control flow-rates
Call us now to get control of your pumping process!