Maric Constant Flow Valves

A tamper-resistant method, of protecting centrifugal pumps from running off their curve, is to place a correctly sized Maric Constant Flow Valve close to the pump discharge.

A common cause of submersible centrifugal pump failure, is that of allowing them to run at below their minimum operating head. This is the same as allowing them to deliver too high a flow rate.

For long trouble-free life, flow rate and head should be maintained within the manufacturers specifications. Pump suppliers should clearly understand the design limits of their pumps.

Pumps can be damaged on:

• Any bore, where people can unwittingly open up the bores’ gate valve in an attempt to increase flow
• High standing water tables
• Empty pipe work at start–up, i.e. lack of, or faulty check valve
• Over-pumping beyond the refill rate, to point of drawing in air or sand
• A burst in the pipework allowing uncontrolled flow
• Pumps with two separate duties; One, a tank elevated 50m up a hill, and the other, to feed a dam at the same elevation as the pump. (A lack of head here on the lower elevation allows flow rate beyond manufacturers specifications
• Rising water tables; Limiting pump peak flow rate can prevent electric motors from overloading as operating head reduces
• Water Authority Policy Changes; The local council mandates that, for the health of the river, property owners must reduce rate drawn from a river, using a non-adjustable flow control device

Key features of Maric Flow Controllers: Why use a  Maric Constant Flow Valve?

• Tamperproof: Maric Constant Flow Valves are non-adjustable, which prevents owners from trying to “get more from their bore”
• Maintenance free, reliable and self-cleaning: As there are no wearing parts, the valves require no maintenance, adjustment or cleaning throughout their 20+ year life span
• Compact: as compared with comparable diaphragm valves
• Automatic: The control rubbers orifice diameter responds automatically to pressure fluctuations