Dragflow hard iron submersible pumps

Euroflo dredging and slurry pump feature a simple design for ease of use and servicing

Euroflo’s Dragflow dredging and slurry pump has a very simple design making it easy to use and service. The agitator picks up materials which are too coarse for pumping and puts solids in suspension; the pump which is positioned above then sucks them in. All wear parts are made of long-life high chromium content. The action of agitator rejects material which is too large, thus preventing it from blocking the filter. The maximum solid handling capacity of Dragflow dredging and slurry pumps is 120mm and the largest discharge in the range goes up to 350mm.

Dragflow dredging and slurry pumps can be supplied in both electrical and hydraulic powered formats. They are used for the dredging of canals and harbours, clean-up of locks, extraction of gravel or sand, emptying of caissons and bulkheads. In mining, Dragflow pumps feature in the clean-up of settling tanks, extraction of coal, minerals and foundry sand. For industrial applications Dragflow slurry pumps are used for the extraction of slag, forge scale, calcines, sludge’s, settling sludges, petroleum and tar residues.

Euroflo supply these pumps to a wide variety of applications. In deep foundation works Dragflow hard iron submersible slurry pumps are used for pumping a CM10 bentonite mix as part of the construction process. These pumps are tough and abrasion resistant, traditionally standard pumps have been used for these slurry pump applications, but with foundation depths that exceed 30m the standard slurry  pumps are put under extreme pressure that can cause premature failures.

Dragflow hard iron submersible slurry pumps offer a variety of HD (high depth) versions for hire or sale to work in deep foundation works that exceed 30m, more typically the working parameters of these pumps is between 40m to 65m deep, but in more extreme application these slurry  pumps can be put to work in applications that exceed 100m.

Dragflow pumps have been selected on a variety of projects because of their ability to pump very abrasive bentonite slurries charged with sand and gravel with a density of 1.3kg/dm3 at these operating depths. Euroflo have supplied pumps to carry out a variety of trials for the recovery of submerged aggregate, as well as applications throughout the quarrying process for mixing and pumping abrasive materials.

For one of Euroflo’s customers in the Republic of Ireland, the company supplied a 6in 50hp (37.5kW) hard iron dredging pump to recover submerged aggregate, which is made up of 60% sand, 30% gravel and 10% stone, with a maximum diameter of 60mm. The pump extracted 100 tonnes of solids per hour at a depth of 15m.

According to Euroflo, using a Dragflow dredging pump gives you an advantage, as they can handle slurries including stones at higher depths than horizontal surface pumps. It is also very important to verify the percentage of stone and their diameter when selecting the pump to ensure the correct selection is made.

Pumping abrasive slurries with low pH is very challenging as conventional pumps fail in highly corrosive environments. Euroflo are able to offer effective solutions in a large number of these applications using specialist pumps. Euroflo supplied an African copper mine with 6in Dragflow  submersible hard iron slurry pumps constructed from cast 316 stainless steel. The pumps were produced to work in extreme environments, typically working in liquids with a pH value of between 2 and 3, which is highly acidic.

Euroflo have seen success when providing Dragflow submersible dredging pumps with agitators in sand recovery and winning applications. For one such project they conducted trials to prove the ability of the pump to recover a high concentration of sand in suspension. Euroflo then used an 8in 37.5kW (50hp) submersible hard iron dredging pump with agitator which, after successful trials, was subsequently purchased. The submersible dredging pump was then attached to its permanent position on a ladder at the front of a self-propelled vessel for dredging with 200m of floating discharge pipe. This submersible pump was powered initially by one of Euroflo’s 80kVA portable rental generating sets, before a unit was eventually purchased and mounted on the vessel.  After 18 months it had produced in excess of 200,000 tonnes of high-quality silica sand, which equates to approx 500 tonnes/day. Pumping high concentrations of sand takes its toll on the pump over time, so every six months the pump is returned to Euroflo’s service centre.