Lineshaft···

Axial and mixed flow pumps that are a tried and true, dependable technology which will meet your needs for high-volume, low head pumping such as flood control, drainage, flood irrigation, water supply, aquaculture, amusement parks and other similar requirements.

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MWI Couch Lineshaft axial and mixed flow pumps are a tried and true, dependable technology that will meet your needs for high-volume, low head pumping such as flood control, drainage, flood irrigation, water supply, aquaculture, amusement parks and other similar requirements.

Lineshaft pumps are traditional pumps that connect the impeller to the drive by means of a long shaft. They are typically driven by diesel or electric motors that can be connected by utilizing a belt and pulley, gear or direct coupling. MWI's lineshaft pumps are offered with both higher-head, mixed flow impellers and low-head, axial flow impellers. They are available in 8" - 144" (0.2 m - 3.7 m) diameters with capacities up to 800,000 GPM (50.5 m3/s). Lineshaft pumps are the most efficient technology yet devised for pumping large quantities of water. MWI is a master designer and constructor of lineshaft pumps with decades of experience and thousands of pumps in use in critical applications where failure is not an option. Our pumps are simple, very robust and extremely dependable. They are fabricated from corrosion resistant steel, stainless steel or cast iron to meet any pumping need.

Why Chose the MWI Lineshaft Pumps?

We've been in the business for over 75 years due to a focus on designing and building great pumps, on pleasing customers and standing behind our products. If it says MWI you can be assured of a quality product and total support.

Experienced engineer staff to insure your pumps are designed to match your needs and provide effective, efficient results.

Designs are rugged and robust for reliability and long life. Many of our pumps are in regular use for over 25 years.

Choice of materials to match the environment and pumped medium.

Multiple drive units and arrangements - electric, diesel or natural gas to provide you with the most reliable and cost effective solution.

Different configurations - horizontal, angled or vertical to provide maximum flexibility.

High efficiency propellers and impellers to increase performance and reduce operating costs.

Thousands in use world wide with a reputation for quality and longevity.

Pump Construction

Shaft & Bearings

Shafts are made from high tensile strength, stress relieved, turned, ground and polished alloy steel. Lower areas of the shaft in contact with bearings or seals are inlayed with hardened stainless steel. Generous safety factors are used to assure power transmission capacity well beyond the maximum horsepower requirements of the pump, allowing for sudden shock loads which may occasionally occur. The shaft is enclosed in a sealed, oil filled tube. The tube contains bronze bearings spaced to prevent operation of the shaft near its critical speed. Oil lubrication is maintained by a reservoir located conveniently near the top of the pump.

Column & Elbow

The discharge column and elbow are rolled from corrosion resistant ASTM A242 steel. The discharge elbow has multiple segments to allow for smooth and efficient flow. The elbow terminates with a flange for a gasket connection to the discharge pipe. The elbow is also available with a plain or grooved end to accommodate compression type couplings.

Pump Bowl

The pump bowl is designed to maintain the highest possible hydraulic efficiency. Because the bowl absorbs much of the hydraulic and mechanical stress, its heavy duty design features corrosion resistant ASTM A242 steel. Bowls for pumps with higher heads have a throttle bearing and pressure relief vent to reduce the hydraulic pressure on the lower seals, thus increasing the life of the seals.

Propeller

MWI Couch Pump propellers are laboratory tested to obtain the highest possible hydraulic efficiency throughout the non-cavitating range of operation. The propeller is manufactured from corrosion resistant ASTM A242 steel to combine maximum design versatility and strength. The propeller is balanced and secured to the shaft on a standard taper with a key and locknut which provides for secure mounting while allowing for easy removal when necessary. This combination of design, balance, and finish qualifies MWI Couch Pump propellers for excellent performance.

One-Piece Pump

Simplicity of design is the hallmark of the MWI Couch one-piece pump. While using the same high efficiency hydraulic design common to all MWI Couch pumps, the one-piece pump features major components permanently welded together to form a rigid, factory aligned unit. Critical alignment of the bearings in the shaft enclosing tube is maintained by support spiders welded to the pump column and hood, and the unique stepped design of the bearings allows easy replacement with a minimum of pump disassembly.

Jointed Pump

The MWI Couch jointed pump allows for complete disassembly of most pump components. The pump bowl is flanged to the column. Pump shaft bearings are threaded into shaft enclosing tube sections. The enclosing tube is put in tension by means of the tube tension nut near the top of the pump. MIXED FLOW BOWL: For higher head applications the mixed flow bowl provides the highest pumping efficiency. Mixed flow bowls come standard with a throttle bearing and pressure relief vent to reduce the hydraulic pressure on the lower seals, thus increasing the life of the seals. A replaceable impeller bowl section is available as an option.

Thrust Bearings

Where the pump is required to carry the hydraulic thrust load, the shaft is supported by heavy duty, duplex mounted, angular contact, ball bearings designed for a combination of thrust and radial loads and a minimum L10 life of 20,000 hours (higher life hours are available).

Thrust Bearings Housing

For belt drive applications, a thrust bearing housing at the top of the pump carries the radial load at the closest possible point to the load. A convenient lubrication port and vent are provided to add new grease and purge old grease from the bearings. This means the original thrust bearings should normally never need to be replaced if they are properly maintained. If service is needed, however, the bearing can be replaced without pulling the pump.

Thrust Bearings Bowl

The pump bowl carries the thrust load at the closest possible point to the load. The bearings operate submerged in oil and are cooled by the surrounding water. The stainless steel bowl shaft is sealed with a high pressure carbon/ceramic mechanical seal. No vertical shaft adjustment is needed, and the pump can run dry for extended periods of time since no tail bearing is required. A flexible coupling connects the bowl shaft to the line shaft and dampens vibration.