When we talk about faucets, taps and showers, we often mention the phrase ‘flow rate’. The flow rate designates the amount of water per minute that flows from the tap or shower. In the US and Britain, the flow rate is commonly defined in gallons per minute (gpm). In the rest of the world, litres per minute (l/min) are used. One gallon equals approx. 3.79 litres.
There are basically two options to control the flow. The simple option is a fixed orifice designed to allow a predetermined flow at a certain specified pressure (e.g. at 3 bar). If the pressure is higher, the flow rate increases; if the pressure drops, the flow rate goes down. At Neoperl, we refer to such products as ‘restricted’ or ‘flow restrictors’.
The other option is to use NEOPERL® products with an integrated flow regulator. They maintain a steady flow rate virtually independent from the line pressure. This saves water, as the flow rate does not go beyond a set value (within a certain pressure range).
The integrated flow regulator consists of a housing and a rubber o-ring. As soon as water flows through with more pressure the o-ring alters its shape and thus makes the openings smaller – the flow rate remains virtually the same.
When there is low or no pressure, the o-ring of the flow regulator is relaxed (position 1).
As soon as water is flowing and the pressure is rising, the o-ring starts changing shape and is pressed into the core’s indentations (position 2). The openings for the water become smaller, less water flows through.
The higher the pressure, the more the o-ring changes shape and the smaller the openings (position 3). Thus no matter how high the pressure is, the water flows at a regulated, virtually constant rate that is comfortable and ecologically sound at the same time.
When the pressure decreases, the o-ring gradually goes back to its regular shape, while the water openings become larger again (back)