Your comprehensive guide to penstock valve

Penstock valve has great importance as a type of gate valve. It also has several advantages that we mentioned in a previous article. With Water Care, you will find answers to all questions related to all types of valves.

Classification of gates:

1. Divided by the nature of work: There are mainly working gates, accident gates, and maintenance gates.
2. Divided according to the method of opening and closing of the gate: mainly use mechanically operated gates and hydraulic automatic gates. That uses changes in water pressure on the gates to control the opening and closing of the gates when the water level fluctuates.
3. Divided according to the different support forms of the penstock leaves: mainly by fixed wheel support gates, hinged support gates, gates supported by slides, sprocket gates, series roller gates, round roller gates, etc.
4. Divided by production materials: mainly wooden penstock, wood panel steel frame penstock, cast iron penstock, reinforced concrete penstock, and steel penstock.
5. Divided by the relative position of the top of the gate and the horizontal plane: there are mainly exposed gates and submerged gates.

The structure of the penstock valve:

The penstock is mainly composed of three parts:

1. The movable part of the main body, used to close or open the orifice, is commonly called the gate. Also known as the door leaf; the movable part includes the panel beam system and other weighing structures, supporting walking parts, guiding and water-stop devices, and lifting lugs.
2. Buried parts: Buried parts include main rails, guide rails, hinge seats, door lintels, bottom sills, water stops, etc. That is buried around the opening and is firmly connected to the concrete of the hydraulic structure with anchor bars. Respectively The supporting walking parts and the water-stop surface are formed on the door leaf. So as to transmit the water pressure and other loads on the door leaf structure to the hydraulic structure and obtain good water-stop performance of the gate.
3. Opening and closing equipment. The opening and closing machinery are connected with the lifting lugs of the door leaf to operate and control the position of the movable part. But there are also a few gates that are opened and closed by hydraulic automatic control.

Selection of the form of the penstock valve:

When selecting the gate type, it needs to be determined through technical and economic comparisons based on the nature of the gate’s work, setting position, operating conditions, gate span, opening and closing force, and engineering cost. Combined with the characteristics of the gate, referring to the existing operating practical experience. And comparing it with technology and the economy. Among them, plane gates and arc gates are the most commonly used gate shapes.

1. Radial penstock: arc gates are mostly used for large, medium exposed top and submerged working gates, and high-head and deep-hole working gates are especially commonly used.
2. Plane penstock: Plane gates are mostly used as accident gates and maintenance gates.

Maintenance gates and accident gates are often set before the working gates. For high-head discharge gates due to frequent water operations or partial openings, efforts should be made to reduce gate vibration and cavitation, improve gate hydraulic conditions, consider the influence of power according to different components, and conduct rigidity and dynamic characteristics of the gate body. Analysis.

The manufacturing and installation accuracy of the door leaf and embedded parts should be strictly controlled. When the boundary of the door slot is complicated or the body shape is special. In addition to the successful test of the existing operation, the hydraulic model test should also be used to solve the possible vibration and cavitation problem, to select the appropriate door slot shape.