3.2.19 Washing pumps
Washing pumps
Washing pumps are pumps for washing purposes e.g. car washing. There are off-the-shelf sets available on the market. Normal data is usually; volume flow rate approx. 40 litres/min With pressure boosting up to approx 1.5 MPa, equivalent to a delivery head of approx. 150 m. The pump section normally comprises of an electrically driven multi-stage turbine pump. To avoid operation while the fluid flow is shut-off, which would cause overheating of the pump, a so-called minimum flow sensor is included in the set. This monitors the fluid flow through the system and prevents the pump from operating in the event of too small a flow of water. A typical type of washing pump is shown in figure 3.219a.
- Shut-off valve. Required for servicing of pump and equipment.
- Filter With cleaning plug. Prevents contaminants from entering the minimum flow sensors.
- Minimum flow sensor. Starts and stops the pump automatically. Connects With single-phase Cable to the motor safety switch. The pump must operate With a supply pressure where the sensor is fitted.
- Non-return valve. Prevents water from flowing back into the pipe.
- Vacuum valve is activated in the event of the water supply pipe failing to supply the quantity of water required by the pump.
- Motor safety switch. Switches off electric current to the motor and triggers alarm signal in the event of a fault arising. Must always be used when a minimum flow sensor is fitted.
- Pressure gauge. Fitted to pump’s delivery flange.
- Solenoid valve. Damp-resistant. Opened and closed by coin slot
- Valve. Equipped with handle and hose connection.
- High pressure hose. If the delivery pipeline is long, a larger diameter should be chosen in order to reduce the pressure drop in the pipeline.
- Wash gun. Completely rubber covered with shut-off and regulating facilities. Can be adjusted between hard impact jet and fine spray.
- Coin slotmeter. For self-service vending. Can be set to time in minutes. Coin setting as required.