By: thamashni naidoo
6th October 2006
The South African Bureau of Standards recognised Hazleton for its Hippo submersible pump range, as well as its vertical-spindle froth-slurry pump.
Company sales and marketing director Johan de Jager says that the Hippo range is the most popular of its kind on the market.
It is South Africa’s only locally- designed and -manufactured submersible slurry pump range cap-able of pumping corrosive as well as abrasive slurries.
Hippo range The submersible slurry pump is designed to allow for operation in fully, partial and nonsubmerged conditions.
The twin-volute casing is designed to balance hydraulic forces exerted on the pump shaft during operation and the features results in extended bearing and mechani- cal seal life.
De Jager explains that the agitator at the inlet to the impeller breaks down and resuspends compacted solids, which enables the pump to transfer a high percentage of solids.
“All the pumps can be supplied with certified flameproof specification.” An advantage of the twin-volute casing, De Jager says, is that the impeller revolving in a single volute-shaped casing is subject to an unbalanced side thrust.
“This side thrust causes increased load on the bearings, resulting in reduced bearing life,” he adds.
Shaft deflection, which is caused by varying loads, especially when pumping heavy slurries, results in mechanical seals having to accommodate the movement, which, in turn, reduces seal life.
Submersible pumps valued at R1,4-million were delivered to the Everest Platinum mine in Rustenberg this year in response to the pressure faced by marginal gold mines to reduce the cost of pumping.
The company developed a low- cost reliable vertical spindle pump using an electrical motor, which is manufactured with a steel enclosure.
“The steel motor eliminates repair costs associated with standard cast-iron motors, which often crack or break when transported underground,” De Jager says.
He states that the first two submersible pumps destined for the oil-sands in Northern Alberta, Canada, were tested at the SABS upgraded test facility.
He adds that the pumps are designed to pump slurry with a specific gravity of 1,74, at a rate of 166/s, with a four-bar pressure.
The Hippo submersible pumps are highly suited to harsh conditions found at oil sands, featuring a double-discharge casing, which reduces radial loads on the shaft and increases bearing and seal life.
The pump motor is cooled by pumping the product through a jacket that surrounds the motor and, owing to hazardous conditions in which the pumps will be working, safety is important.
For this reason, the pumps are fitted with temperature sensors for the motor windings and the bearings. The chambers also have double seals. The casing, impeller and liners are manufactured from hardened high-chrome castings, but could be manufactured from a variety of other materials, including stainless steel.
“The vertical cantilever design eliminates submerged bearings and the top suction design eliminates air binding, which allows the pump to run dry and quickly reprime when required,” De Jager maintains.
The twin volute casing design balances the radial loads created by the impeller and casing in the most efficient way, assuring a trouble-free installation with a long bearing life.
Added flexibility is provided through different wet-end designs, which meet various slurry requirements.
De Jager adds that castings can also be supplied in materials more suitable for abrasive, corrosive or combination applications.
“Many vertical slurry pumps are of single-volute design and some are provided with a splitter, which results in a double-volute design.” This is effective under certain flow conditions, but the thrust balan- cing is not as complete as with the Hippo Twin-volute.
Hazleton delivered two vertical-spindle froth-slurry pumps to the Apatit phosphate mine in Russia earlier this year.
The order was valued at some R1-million and Hazleton designed and manufactured the largest vertical spindle pump to ever be produced in a matter of four months.
De Jager says that the company has received many orders for the pump since, with its key client being AngloCoal.
“One of the main design features often highlighted by customers is the pump’s ability to run dry without detrimental effect to the pump seals,” says De Jager.
When it comes to maintaining the pump, customers are also surprised at the reason-ably-priced, freely-available, John Crane seals which offer exceptional reliability while seals on many of the more commonly used submersible pumps are extremely expensive and can not be run dry.
VNR Another new Hazleton product is the VNR nonclogging slurry pump. This pump works well on chunks of coal, rock and shale, chemical waste and sludge-floor cleanup.
“We deal in superior resis- tance, which has a unique combination of rugged design and proven abrasion and corrosion metallurgy.” The product eliminates all clogging caused by debris, which includes rags, rubber gloves, fibrous material and even soda cans.
Capable of running dry, the self-priming Hazleton VNR has no submerged bearing and requires no level control.
“Essentially self-regulating, it reprimes without surging as soon as liquid covers the impeller,” De Jager continues.
Hazleton’s latest development, with assistance provided from Alstom, is the first high-voltage submersible slurry pump.
De Jager says that the company has received several requests from mines, both locally and internationally, for the high-voltage pumps.
The pumps will mainly be used for process and storm-water management, high-volume pond distilling and mine dewatering.
Despite the volatility of the rand, De Jager says that the company sales has doubled in the last six months or so, which has forced the com- pany to expand its outreach.
Hazleton has since employed more staff and has trained addi- tional staff in all areas, especially in the manufacturing department.
“The increase in production of large-capacity pumps has resulted in the procurement of additional equipment for the machining faci- lity and has placed the need for additional factory space high on the agenda,” he comments.
The company has supplied some 5 000 of its pumps to diamond, gold, coal and platinum mines since its inception in 1988.
Hazleton provides a profitable, sustainable service and aims to become a leading entity through continuous development and themanufacture of quality pumps and related products.
More about Hazleton MD Mathys Wehmeyer started the company in 1988, buying most of the manufacturing equipment at auctions, and then refurbishing it. All the Hippo slurry pump components are manufactured in-house.
The company provides a profitable, sustainable service and aims to grow into a leading company through continuous development and the manufacturing of quality pumps and related products.
Edited by: thamashni naidoo