Dewatering pumps and accessories from a Dutch expert are being promoted in the Gulf by Alaa Industrial Equipment Factory (AFI) of Saudi Arabia.

The GEHO dewatering systems from EnviroTech Pumpsystems Netherlands are specifically targeted at the construction industry and have already been used on major projects in Bahrain and Saudi Arabia, says AFI's marketing manager Jolly Joseph.

"Over half a century, Geho Pumps has acquired specialist knowledge about dewatering systems through research and development and the company today offers a purpose-built range of well-point dewatering pumps and well-point equipment accessories, as well as expertise in services ranging engineering to installation and supervision," he says. "GEHO's open and well-point dewatering systems are used throughout the world to the satisfaction of international construction companies."

He continues: "AFI is one of the leading suppliers of industrial equipment in the Middle East. AFI has always used its long-term vision when choosing partners in its 17 years of existence. Today, major industrial houses understand and appreciate the expertise and experience AFI possesses in the region. The AFI-GEHO partnership is a natural extension of both companies' commitment to have right partners while providing products and services in the marketplace."

"Well-point dewatering systems enable the lowering of the groundwater table adequately for deep and large construction sites. The water from highly permeable soils is pumped from well points installed along the trench of the site. The well points are jetted and spaced to obtain an efficient draw down against the lowest capacity, The well points with integral strainers are joined to transparent flexible hoses, which are connected by quick-release couplers to equi-spaced ring receptacles of the main header pipeline. Well-point dewatering is done either by gravity or vacuum."

AFI is currently focusing on GEHO's ZD series of twin-cylinder, quadruple-action crankshaft-driven vacuum piston pumps which is said to be extremely suitable for well-point dewatering by gravity or vacuum and for horizontal dewatering.

Joseph explains: "The pumps feature tough compact construction with integral single helical precision gears, self-contained oil splash lubrication, Meehanite disc-type pistons with double cup leathers, precision-machined wear-resistant and easy replaceable stainless steel liners, one-piece abrasion and corrosion-resistant hard surface piston rod, flat spring-loaded brass valves with rubber discs and stainless steel guides. The crankcase, liquid end and pistons are made from Meehanite cast iron. They have large inspection covers, cross head and connecting rod sleeve bearings, an anti-friction drive shaft and crankshaft bearings.

"When in operation, water or air or a water-and-air mixture are primed and discharged four times per crankshaft revolution. Two crankshaft-driven pistons are arranged in a 'V' at 90-degree angles, so that the four piston strokes for each revolution follow in regular succession. The crank timing produces a moderate pulsating action in the dewatering line that prevents clogging of the well-point strainers and achieves priming at greater depths. The flow and pressure fluctuations in a duplex pump are inherently more favourable than in a simplex pump.

"GEHO pumps offers several benefits. They ensure a constant water and air flow, independent of the suction and discharge head. They are self-priming with a suction lift (vacuum) capability of 9.6 mWC without the aid of a separate power-absorbing vacuum priming pump and the pulsating vacuum prevents well-point clogging.

"Their robust design enables ease of transportation and handling and their high efficiency minimises energy consumption. They are twice as efficient as conventional vacuum priming impeller pumps.

"The pumps allow for quick maintenance, as no special skills are required to inspect and maintain them and they have a low incidence of spare parts use.

''They are resistant to brackish water and their long service life helps reduce overall project costs. Also, depending on soil conditions, as many as 100 well points and up to 300 m of header pipe can be connected to a single pump."

Headquartered in Dammam, AFI has offices in Riyadh, Jeddah, Yanbu, Hofuf, Jubail and Khodariya within the Kingdom, and regional offices in Bahrain, Qatar and Kuwait. "With an experienced and highly-skilled workforce across the region, AF'I is well positioned to give a better service and technical support to its customers," Joseph says.