Progressive Cavity Pump Upgrade Slashes Maintenance Costs
Project Overview
Modern progressive cavity pump upgrade delivers cost and performance benefits for china clay producer.
Challenge
In the process of refining high-quality kaolin clay, the quarried slurry is thickened before passing through vibrating screen decks to grade the material and remove the gangue. The site’s legacy progressive cavity (PC) pump, which extracted thickened sludge from the thickener tank, required frequent gland repacking and wear-part replacement. In addition to the direct maintenance costs, this led to downtime and inefficiency in downstream processes.
Eliminating leakage was crucial to prevent product loss, wash-down costs, and pump maintenance. Once high-solids content sludge starts to weep out through the seals, a trickle can turn into a fountain very quickly.
Evaluating the refurbishment requirements, the cost and lead times of the (imported) parts prompted a re-evaluation of the pump choice.
Pump reliability and performance are vital for manufacturers of fine mineral products, so reducing time between maintenance and spare-part availability is crucial.
Having partnered with Atlantic Pumps on several specialist pumping projects with good results, the client commissioned them to supply and install a pump solution that would give them longevity in the application without premature wear or early component failure.
They also wanted the assurance of Atlantic Pumps’ back-up and support for spares and servicing when the time comes for this process-critical pump.
The required flow rate was a stable 29 m3/h. The thickened Kaolinite sludge has a high dry matter (DM) content and is thixotropic, making low-shear pumping important.
Solution
The sludge’s density, shear-sensitivity, and fines suspension indicated that a progressive cavity type pump remained the right choice, and the modern Toro-Kronoa PC pump offered a clear reliability and performance upgrade over the legacy one.
Atlantic Pumps recommended the Toro S50 300-06 with a cartridge-type mechanical seal, advanced cardon joint drive shaft, hard chrome plated (HCP) steel rotor, and an efficient motor to match the duty. The stator material was chosen for a balance of lifetime cost, abrasion/slippage resistance, and thermal stability.
A short-pitch rotor/stator geometry enables the flow rate to be achieved at a low rotational speed, which further extends wear life, saves energy and protects the clay’s structure from excessive shear stress. The maximum pressure rating of the standard, single-stage pump easily covered the system requirements.
Results
Long wear life – more uptime – less maintenance – energy savings
The new PC pump has a smaller footprint thanks to its modern, efficient design, and its additional features make it much more robust. The raw cost savings from spares and maintenance alone justified the upgrade, with system-wide efficiency gains and capacity improvements secured in addition.
Toro-Kronoa pumps have an energy-efficient design, enabling, in this case, the use of a 7.5 kW motor – down from 18 kW on the old pump.
The seal upgrade has resulted in zero leakage – increasing product yield, reducing cleanup duties, and eliminating the need to reprocess wash-water effluent. The total cost of this pump upgrade compares very favourably with that of refurbishing the old one, and with parts stocked at Atlantic Pump’s central UK store, the client can expect faster lead times and better service when the time comes to replace wear parts.
A robust pump like this enables optimal performance and maximum uptime of the downstream processes.
As the client sums it up, “The (Toro-Kronoa) pump is more robust, more fit for purpose than previous pumps used as well as being competitively priced.”
This pump has been running for over six months and we don’t see any visible sign of wear at this point.
Operations Manager, China Clay Quarry
To discuss pumping solutions for your industrial site, contact Fergus Pridham (heavy industry lead) or Euan Davies, South West England regional manager, Atlantic Pumps.
