Roger Mardon fire service history

Fire service historian and author

Roger Mardon

www.romar.org.uk

The submersible pump is connected to the Hydrosub module by two 60 metre hydraulic hoses and as the pump is removed via a ramp and deployed these hoses are payed out by the operator using a pendant control. The pump can be wheeled to its operating position in the water up to 60 metres away and a winch is provided to aid deployment and recovery.

The Hydrosub diesel engine drives an oil pump and as the engine revolutions are increased the hydraulic pressure and flow rate of the oil increase to drive the impeller of the submersible pump via a high pressure feed and a low pressure return through the hydraulic hoses. An on-board computer is used by the pump operator to calculate the distance over which water can be pumped and the rate of flow, according to the end pressure, the lift (the vertical distance water has to be raised), the head (the rise in ground level to the point of discharge) and the number of hose lines. The hydraulic hose reels and the winch are also driven by the hydraulics but at tick-over speed.