What does the knife gate valve dark plate mean? Is it a dark rod knife gate valve?

The dark plate of the knife gate valve refers to the connecting parts between the valve stem (or valve stem and valve shaft) and the gate plate (or knife plate and valve plate), which is usually connected by threads or keys to fix and transmit the operating force.

Dark plate knife gate valve refers to a kind of knife gate valve in which the valve stem is fixed on the inside of the gate through the valve bearing, and the valve stem is not exposed to the outside of the valve. Compared with the outer stem knife gate valve, the dark stem knife gate valve can avoid the exposed valve stem, reduce the risk of valve stem damage and leakage, and is suitable for some high-demand process occasions.

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. Although the ranking may change due to time and market conditions, the following brands are generally considered to be among the top brands in the valve industry: Water System Valves and Industrial ValvesThe following more influential first-line brands can be used as a reference, but are for reference only:

Suzhou Neway Valve Co., Ltd., Shanghai Guanlong Valve Machinery, Shanghai Qizhong Valve Manufacturing, Sanhua, Su Yan, Shentong, Su Valve, Nanfang, Jiang.

First, the word Yao. The above manufacturers are only estimates and references, and the specific situation may vary or fluctuate at any time due to changes in a series of factors such as changes in the market, the size of the competition pattern, and the stability of product quality. As an indispensable key device in industrial production and civil facilities, the quality and reputation of the valve brand directly affect the satisfaction and trust of users.

These brands are known in the valve industry for their innovative technology, high-quality products and reliability. It is important to note that the market and industry are evolving rapidly, and different rankings may vary depending on time and region. For the most up-to-date ranking information, it is recommended to refer to industry reports, professional organizations or market research data for more detailed and accurate information.

That's not what you mean.

The open rod and dark rod are whether the bearing of the valve rotation can be seen, and the blind rod can not be seen, and the open rod can be seen.

The dark plate is the valve plate in the valve body, you can't see it, and the knife gate valve is generally an open plate

Dark rod knife gate valve: (also known as knife gate valve) The opening and closing parts of the knife gate valve are the gate, and the direction of movement of the gate is perpendicular to the direction of the fluid, and the manual knife gate valve can only be fully opened and closed, and cannot be adjusted and throttled. The ram has two sealing surfaces, and the two sealing surfaces of the most commonly used mode gate valve form a wedge, and the wedge-shaped angle varies with the valve parameters, usually 50, and the gate of the wedge-type knife gate valve can be made into a whole, which is called a rigid ram; Also available.

In order to make a gate that can produce a slight amount of deformation, in order to improve its manufacturability, make up for the deviation of the sealing surface angle in the processing process, this kind of gate is called elastic gate When the knife gate valve is closed, the sealing surface can only rely on the medium pressure to seal, that is, the sealing surface of the gate is pressed to the valve seat on the other side by relying on the medium pressure to ensure the sealing of the sealing surface, which is self-sealing. Most of the knife gate valves are forced sealed, that is, when the valve is closed, the ram should be forced to the valve seat by external force to ensure the tightness of the sealing surface.

Entered our country from the eighties. In less than two decades, its use has expanded from the general field to a wider range of industries. Coal preparation, gangue discharge, and slag discharge from mining power plants.

It has developed into urban sewage treatment, from general industrial pipelines to professional pipeline systems such as food, sanitation and medicine. With its advantages of small size, small flow resistance, light weight, easy installation and easy disassembly, the ultra-thin knife gate valve completely solves the difficult problems of large flow resistance, large weight, difficult installation and large floor space of ordinary gate valves, flat gate valves, ball valves, globe valves, regulating valves, butterfly valves and other valves. After the advent of knife gate valves, a large number of general purpose shut-off valves and regulating valves have been replaced.

To this day, the largest number of knife gate valves in the world are the United States and Japan.

This type of valve should generally be installed horizontally in the pipeline.

Precautions and characteristics of the dark rod knife gate valve in the use of the product: The opening and closing parts of the knife gate valve are the ram, and the direction of movement of the ram is perpendicular to the fluid direction, and the knife gate valve can only be fully opened and closed, and cannot be adjusted and throttled. The ram has two sealing surfaces, and the two sealing surfaces of the most commonly used mode gate valve form a wedge, and the wedge-shaped angle varies with the valve parameters, usually 50, and the gate of the wedge-type knife gate valve can be made into a whole, which is called a rigid ram; It can also be made into a ram that can produce a slight amount of deformation, in order to improve its manufacturability, make up for the deviation of the sealing surface angle in the processing process, this ram is called the elastic ram When the knife gate valve is closed, the sealing surface can only rely on the medium pressure to seal, that is, the sealing surface of the ram is pressed to the valve seat on the other side by relying on the medium pressure to ensure the sealing of the sealing surface, which is self-sealing.

Most of the knife gate valves are forced sealed, that is, when the valve is closed, the ram should be forced to the valve seat by external force to ensure the tightness of the sealing surface.

Dark rod knife gate valve: (also known as knife gate valve) The opening and closing parts of the knife type or dismantling gate valve are the ram, and the movement of the gate is perpendicular to the direction of the fluid, and the manual knife gate valve can only be fully opened and closed, and can not be adjusted and throttled.

The ram has two sealing surfaces, and the two sealing surfaces of the most commonly used mode gate valve form a wedge, and the wedge-shaped angle varies with the valve parameters, usually 50, and the gate of the wedge-type knife gate valve can be made into a whole, which is called a rigid ram; It can also be made into a ram that can produce a slight amount of deformation, in order to improve its manufacturability, make up for the deviation of the sealing surface angle in the processing process, this ram is called the elastic ram When the knife gate valve is closed, the sealing surface can only rely on the medium pressure to seal, that is, the sealing surface of the ram is pressed to the valve seat on the other side by relying on the medium pressure to ensure the sealing of the sealing surface, which is self-sealing. Most of the knife gate valves are forcibly sealed, that is, when the valve is closed, the ram should be forced to the valve seat by external force to ensure the tightness of the sealing surface.

The opening and closing parts of the dark rod gate valve are the ram, the direction of movement of the ram is perpendicular to the direction of the fluid, and the gate valve can only be fully opened and closed, and can not be adjusted and throttled. The ram has two sealing surfaces, and the most commonly used mode gate valve has two sealing surfaces forming a wedge, and the wedge angle varies with the valve parameters, usually 50, and 2°52 when the medium temperature is not high'''' 。The gate plate of the wedge gate valve can be made into a whole, which is called a rigid gate; It can also be made into a ram that can produce a slight amount of deformation to improve its manufacturability and make up for the deviation of the sealing surface angle in the processing process, which is called the elastic ram.

Dark rod gate valve is also called rotary rod gate valve (also known as dark rod wedge gate valve). The stem nut is located on the ram, and the handwheel rotates to drive the valve stem to rotate, and the ram is lifted, usually there is a trapezoidal thread at the bottom of the valve stem, and through the thread at the bottom of the valve and the guide groove on the valve disc, the rotary motion becomes a linear motion, that is, the operating torque becomes the operating thrust. When the valve is opened, when the ram lifting height is equal to 1:of the valve diameter

At 1x, the passage of the fluid is completely unobstructed, but this position cannot be monitored during operation. In actual use, it is marked by the apex of the valve stem, that is, the position that cannot be opened, as its fully open position. In order to account for the lock-up phenomenon of temperature changes, it is usually opened to the apex position and then reverted back to 1 2 1 turns as the position of the fully open valve.

Therefore, the fully open position of the valve is determined by the position of the ram (i.e. the stroke).

Dark-rod knife gate valves are either metal-to-metal hard seals or metal-to-rubber soft seals. In the process of opening and closing, the ram and sealing surface are specially designed, which has less friction and is durable. The upper seal of this kind of knife gate valve breaks through the conventional sealing form, and adopts the upper cover structure, so that the upper seal is changed from a large-area rectangular seal to a small-area circumferential seal, and the sealing performance is greatly improved.

On the basis of the circumferential seal, the current international advanced floating seal structure (see Figure 1) is adopted, so that the upper seal reaches the same life as the pipeline, so as to improve the service life of the valve as a whole. After this kind of gate valve is equipped with an envelope device at the top of the handwheel, all the moving parts of the valve can be in a closed state, and the screw drive of the gate plate and valve stem will not be stuck due to the drying of the lubricating oil. It is especially suitable for long-term normal operation in the harsh environment of dust and drying.