Specification of Gauging And Control Structures
Description of Gauging and Control Structures
The two types of adjustable sluice gate, undershot and overshot, are widely used for the control of water in canal systems. In the absence of more accurate devices they may be used for the approximation of flow rates.Sluice gates are made from stainless steel and plastic and are designed to fit in a rectangular section channel 450mm wide.
Automatic Water Control Gates
Automatic control gates are used extensively in canal systems for regulating water levels and discharge. They are usually float operated and are designed to maintain constant levels in the canal so that discharges from off takes can be kept at a constant known rate.
Float Operated Radial Gate
This is a counterbalanced radial-type gate which is controlled by means of a displacer located in a chamber. The displacer chamber is fed with upstream water via a vee notch weir and water is discharged from the chamber downstream through a circular orifice. The flow through this orifice may be adjusted by means of a throttle valve, altering the characteristics of the gate as required. The gate, of the undershot type, provides upstream level control and is designed to fit in a rectangular channel section 450mm wide.
Float Operated Tilting Gate
This consists of a gate flap which is hinged at the base, The position of the gate is controlled by means of a displacer housed in a chamber. Water is fed to the chamber from the upstream side over a vee notch weir and discharged downstream through an orifice. A throttle valve allows the orifice flow to be controlled and the gate characteristics to be modified as required. The gate, of the overshot type, provides a further method of control of upstream level and is designed to fit in a rectangular channel section 450mm wide. This is a radial-type gate incorporating bouyancy tanks.
Floating Weir Gate
This is a radial-type gate incorporating bouyancy tanks. The gate floats at a constant depth so the head of water over the gate crest therefore the flow, remains constant despite variations in upstream level. The gate is suitable for applications where constant flow is required, for example in irrigation canal off takes and is designed to fit in a rectangular channel section 450 mm wide.