Abstract: A controller adjusts the output pressure (P2) of a pressure reducing valve supplying water to a consumer region. The controller includes a clock and aims to reduce output pressure, whilst still providing a minimum required pressure at a critical point (CP) in the region, by adjusting the output pressure in accordance with both the flow rate into the consumer region and with time.

Abstract: A controller (8) for a pilot valve (102) which adjusts the output pressure of a pressure reducing valve (44) supplying water to a consumer region (3). With the aim of reducing output pressure whilst still providing a minimum required pressure at a critical point (CP) in the region, the controller adjusts the output pressure in accordance with the flow rate. The controller includes a clock (22) and the relationship between the required output pressure and the measured flow rate is time dependent. Parameters which define the relationship are supplied to the controller (8) from a remote data processing system (13) which analyses flow rate and output pressure data transmitted from the controller, and also pressure data from a remote sensor (10) at the critical point. At intervals, the controller (8) establishes a wireless connection with the remote system (13), to transmit logged data, and to receive parameters covering a period of time which is greater than the interval between communication sessions.

Abstract: A pilot valve (2) for controlling operation of a hydraulically-actuated pressure reducing valve, the pilot valve including a housing (4), and a first valve member (15) mounted in the housing for longitudinal movement along an axis relative to the housing and to a second valve member (22) in response to the outlet pressure of the pressure reducing valve. The first valve member is provided with an aperture (20) and the second valve member comprises a closure portion which varies the effective flow cross section of the aperture in accordance with relative longitudinal movement between the first and second valve members. An adjuster (26) controls the relative rotational position of the first and second valve members, the closure portion having a profile such that relative rotation between the first and second valve members causes the closure portion to vary the effective flow cross section of the aperture (20).

Abstract: A controller (8) for a pilot valve (102) which adjusts the output pressure of a pressure reducing valve (44) supplying water to a consumer region (3). With the aim of reducing output pressure whilst still providing a minimum required pressure at a critical point (CP) in the region, the controller adjusts the output pressure in accordance with the flow rate. The controller includes a clock (22) and the relationship between the required output pressure and the measured flow rate is time dependent. Parameters which define the relationship are supplied to the controller (8) from a remote data processing system (13) which analyses flow rate and output pressure data transmitted from the controller, and also pressure data from a remote sensor (10) at the critical point. At intervals, the controller (8) establishes a wireless connection with the remote system (13), to transmit logged data, and to receive parameters covering a period of time which is greater than the interval between communication sessions.

Abstract: A pilot valve (2) for controlling operation of a hydraulically-actuated pressure reducing valve, the pilot valve including a housing (4), and a first valve member (15) mounted in the housing for longitudinal movement along an axis relative to the housing and to a second valve member (22) in response to the outlet pressure of the pressure reducing valve. The first valve member is provided with an aperture (20) and the second valve member comprises a closure portion which varies the effective flow cross section of the aperture in accordance with relative longitudinal movement between the first and second valve members. An adjuster (26) controls the relative rotational position of the first and second valve members, the closure portion having a profile such that relative rotation between the first and second valve members causes the closure portion to vary the effective flow cross section of the aperture (20).