Toro Progressive Cavity Pumps – Powered by Kronoa
The properties of progressive cavity pumps make them a good potential choice for transferring thick slurry and sludges. At the same time, they have become notorious for rapid wear and maintenance headaches, even being dubbed as the “pump of last resort”.
It is the raw advantages of PC pump technology that is largely to blame for their misuse. Being ideal for high-pressure/low-flow pumping of shear-sensitive and high-viscosity sludges, they have often been installed in instances where the abrasive or corrosive nature of the media is more than they can handle.
Atlantic Pumps – A Better PC Pump Experience
Atlantic Pumps has long been working with clients to reduce their pump maintenance costs and downtime, particularly in abrasive and highly aggressive PC pump applications. The scope has ranged from providing rapid and dependable delivery of spare parts, advice on pump system optimisations, and installation of alternative rotary PD (positive displacement) pump technology such as LSM, if that better suits a particular application.
Now, with our years of practical progressive cavity pump experience, combined with the additional manufacturing strengths of Kronoa, Atlantic Pumps has launched a new Toro PC pump range that exceeds every requirement of its target application: the T-Line range.
Toro T-Line Progressive Cavity Pumps, Powered By Kronoa
Today’s story of Toro progressive cavity pumps began in 2020 when pump experts and engineers came together to study and resolve every issue they found with the current PC pumps market offering.
June 2024 marked the ‘graduation’ and public launch of the Toro/Kronoa PC pumps. This is an upgraded progressive cavity pump designed for, and tested in, problematic applications in anaerobic digestion, biogas, recycling, and processing factories.
Each design detail is optimsed for performance in heavy-duty applications, and the entire pump is manufactured and assembled in Europe to guarantee quality and speed of delivery. From built-up pumps to spare parts, delivery times to UK and Eire are now half the industry average.
High-Pressure, Leak-Free Mechanical Seal
The sealing system is crucial on progressive cavity pumps and is the source of potential trouble if any shortcuts are made here. So, Toro’s new PC pumps use a robust mechanical seal cartridge that is lubricated by its own dedicated oil supply, rather than relying on the media being pumped. The Toro mechanical seal withstands high pressure (23 bar) and high temperature (150oC).
A roller bearing supports each end of the shaft reducer, isolating the drive gear from axial and radial forces to keep vibration, wear, and excessive strain to a minimum.
Enclosed And Over-Sized Carden Transmission Shaft
The large-diameter carden shaft is made from weld-free modular components and is encased inside a reinforced flexible sleeve – preventing rag entanglement. At the interface of the carden joint and fluid intake, replaceable vanes work to crush up bio-solids and protect the main coupling. We’ve yet to have one of our carden joints break (even after putting it through some heavy axial and radial force), but repairs are inherently easy and cost-effective due to their modular construction.
The need for a robust and precision-made transmission shaft should not be overlooked; a pump rotating at 300rpm will do 70 million mini ‘hits’ a year if working five 8-hour days a week.
The new Toro T-Line progressive cavity pumps are built to avoid this being such a familiar sight:
Above: Done their day; prematurely failed pc pump transmission coupling rods.
Ports, Ports And More Ports
We know that easy and safe access for inspection and servicing is something pump engineers and plant managers greatly value. So, our designers went overboard and added four inspection ports, as big as the casing could take.
The result is the fastest inspection routines and troubleshooting possible, increasing uptime and staff efficiency.
To minimise entrapment injury risk, a safety lock system prevents the shaft from rotating during disassembly.
PC Pump Geometry; S Pitch vs L Pitch
The majority of progressive Cavity pump stators are one of two pitch types: Short (S) and long (L) profiles.
Instead of going for the L geometry used by many pc pump brands (which is easier to manufacture), Toro chose the S-type geometry as standard for the new T-Line range. This gives more thrust for a higher flow and pressure at a lower run speed, even with very thick sludge. It also allows larger solids to pass through than the basic L geometry does and reduces wear in highly abrasive applications.
Larger cavity size, as well as being able to handle suspended solids better, has many benefits for pump wear life. By reducing the rotation speed for the required output, users experience lower operating costs, lower shear, reduced temperature and pulsation, and greater asset lifetime.
The standard Toro S rotor produces up to 12 bar of pressure. If a higher pressure is desired, the H-type rotor is used, which is capable of up to 24 bar.
Media to be pumped | Typical challenges & characteristics | Example Toro T-Line PC pump speed (RPM) range |
Dewatered sludge | High dry matter, abrasive, prone to bridging | 35 – 50 |
Waste, gritty AD-feedstock (sand, concrete debris, bio-matter) | Highly abrasive, sharp stones | 68 - 120 |
Sludge and manure application | Fibrous, heavy, soft-solids | 165 - 270 |
Oils, polymers, glycols and similar | Smooth, non-clogging, self-lubricating liquids | 350 - 430 |
PC Pumps For Medium To High Corrosive Media
All Toro PC pumps cast iron parts and internal 'wet parts’ are treated to withstand corrosion. As standard, all parts are thoroughly cleaned, and then phosphate coated before final coating. The topcoat is either power-coated for use in medium corrosive environments or electroplated with a cataphoretic procedure for more intensive anti-corrosive requirements.The new Toro T-Line range, powered by Kronoa, is proving to be a game changer in PC pumping, reducing downtime, manual repair work, waits for parts, and expensive replacements in abrasive and corrosive pumping applications.
The pumps can be supplied with various intakes including pipe suction, hopper feed, and the Biomix – a mixing pump with a stone catcher. There are also automation, control, and monitoring modules available for optimising plant efficiency.
The exact choice of model and build options comes down to a number of factors, which your Atlantic Pumps’ technical sales advisor can help you with.
Tell us your PC pump challenges today, for a potential solution within days. Here are some factors that might affect which progressive cavity pump model is best for your situation, and what your pump specifier will be interested to know:
- The application and industry, eg material pumping in the recycling industry, or digester feedstock in the AD industry. This will give a head-start on understanding what is being pumped and the challenges faced in similar use cases.
- Where does the media come from, and where will it be discharged?
- What does the liquid/slurry consist of?
- If a replacement for another solution, what will it be replacing and what problems have you encountered previously?
- Dry-matter percentage, pH, temperature, specific gravity and viscosity? The accuracy needed depends on the application.
- Type of solids (soft, hard, angular, rounded), and maximum size? This provides a guide as to its abrasiveness, helping to get the right stator/rotor material choice (alloy, rubber etc).
- Is it corrosive? This will affect the specification of wet-part material and linings.
- Pipework length and diameter (if existing)? Best practice is to have equal or larger diameter piping at the infeed/suction end. A correctly installed eccentric reducer can help prevent air from entering the pump.
- Flow, volume, and pressure requirements. Generally, with PC pumps, it’s best to achieve this at a low rotation speed (RPM). Your pump advisor will select a model with a BEP (best efficiency point) that closely matches the application’s requirements.
Get In Touch
We encourage you to reach out to us early on when researching pump options, as our advisors are happy to give advice and help you get to the best solution quicker.
Whether you are looking to improve your existing pump operations, or want to get your new installation off to the best possible start, get in touch with Atlantic Pumps to discuss your site’s needs today.