covnaactuator-pneumatic-metal-seated-butterfly-valves

What Is Hard Seated Butterfly Valve

The valve is a control component in the fluid conveying system. It has the functions of cut-off, regulation, diversion, prevention of reverse flow, stabilization, diversion or overflow and pressure relief. Valves used in fluid control systems, ranging from the simplest shut-off valves to the various valves used in extremely complex automatic control systems, have a wide range of varieties and specifications. Valves can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media.

Sometimes we will encounter high-temperature, high-pressure, and large-sized pipes. At this time, we will need a hard-seated butterfly valve. Hard seated butterfly valve means using metal as the sealing which could withstand high temperature and high pressure. Hard seated butterfly valve could operate by manual, electric or pneumatic to meet your different applications.

Product Features Of Hard Seal Butterfly Valve

1. The hard-sealed butterfly valve adopts a three-eccentric sealing structure, the valve seat and butterfly plate are almost wear-free, and it has excellent sealing performance.

2. The sealing ring is made of stainless steel, which has the dual advantages of metal hard seal and elastic seal. It has excellent sealing performance, corrosion resistance and long service life regardless of low temperature and high temperature.

3. The sealing surface of the butterfly plate adopts metal sealing, the sealing surface is wear-resistant and has a long service life.

4. The large-size butterfly plate adopts the quilted frame structure, which has high strength, large flow area and small flow resistance.

5. The hard-sealed butterfly valve has a two-way sealing function. It is not restricted by the flow direction of the medium during installation and is not affected by the spatial position. It can be installed in any direction.

6. Electric driving device or pneumatic driving device can be installed to meet your needs in different working conditions.

covnaactuator-electric-gate-valves

What Is Electric Gate Valve?

Electric gate valve refers to the linear movement of the electric gate valve actuator through electric voltage and signal control to open or close the gate valve. Electric gate valves can help you achieve the purpose of remote control, help you reduce labor costs, and improve production efficiency.

Electric gate valve is one of the most commonly used cut-off valves, mainly used to connect or cut off the medium in the pipeline, not suitable for adjusting the flow of the medium. The gate valve is suitable for a wide range of pressure, temperatures and caliber, especially suitable for medium and large diameter pipelines.

Electric gate valve is suitable for water, oil, cement, paper pulp and other media, and is widely used in paper and pulp, power plant, shipyard, wastewater treatment and so on.

The Main Advantages Of Electric Gate Valve

1.1 The fluid resistance is small. The internal medium channel of the gate valve body is straight, and the medium does not change its flow direction when it flows through the gate valve, because the opening and closing is more labor-saving. When opening and closing, the direction of movement of the gate is perpendicular to the direction of medium flow. Compared with the stop valve, the opening and closing of the gate valve is more labor-saving.

1.2 The flow direction of the medium is generally not restricted. The medium can flow in any direction from both sides of the gate valve, and both can achieve the purpose of switching on or off. Easy to install, suitable for pipelines where the flow direction of the medium may change.

The Structure Of The Gate Valve

Gate valves are divided into rising stem gate valves and non-rising stem gate valves according to the stem structure and movement mode.

The stem of the rising stem gate valve drives the gate up and down together, and the drive thread on the stem is outside the valve body. Therefore, the opening and closing and position of the gate can be intuitively judged according to the movement direction and position of the valve stem, and the drive thread is convenient for lubrication and it is not corroded by the fluid, but it requires a larger installation space.

The drive thread of the non-rising stem gate valve is located inside the valve body. During the opening and closing process, the valve stem only rotates, and the gate moves up and down in the valve body. Therefore, the height dimension of the valve is small. Non-rising stem valve gates are usually equipped with an opening and closing position indicator above the valve cover, so as to be suitable for ships, pipe trenches and other environments with small spaces and high dust content.

Gate valves can also be divided into wedge type and parallel type according to the structure of the gate.

Wedge gates can be divided into rigid single gates, flexible single gates and double gates.

The wedge-type rigid single gate is simple in structure, small in size, and reliable in use. However, the processing and matching accuracy of the wedge angle is relatively high, and it is prone to clamping and scratching. It is suitable for gate valves of various media and pressures at room temperature and medium temperature.

The wedge-type elastic single gate can rely on the compensation effect of the slight elastic deformation of the gate to achieve a good seal, the temperature change is not easy to cause wedging, and the accuracy of the wedge angle is low. However, it should be prevented that the closing torque is too large and the ram loses its elasticity. It is suitable for gate valves of various temperatures and pressures.

The wedge-type double gate has low processing accuracy requirements for the wedge angle of the sealing surface, easy to seal, and it is not easy to cause jams and scratches due to temperature changes. It is easy to maintain after the sealing surface is worn. However, the structure is more complicated, the parts are more, and the valve is larger in size and weight.

The parallel single gate has a simple structure and cannot achieve forced sealing by itself. In order to ensure its sealing performance, a fixed or floating soft seal is generally used. It is suitable for medium and low pressure, large and medium diameters, and the medium is oil or gas and natural gas.

Parallel double gates generally generate sealing force through the top wedge, and the relative movement between the sealing surfaces is small, and it is not easy to scratch. It is mostly used for low pressure, medium and small diameter gate valves.