Introduction: The butterfly valve is also called the seated butterfly valve. This butterfly valve is essential for water treatment and industrial water supply, and it is widely used in many industries. The seated butterfly valves are designed with PE (polyethylene), PVDF (polyvinylidene fluoride), or PFA (perfluoroalkoxy) materials, and they can be used for both high temperature and pressure applications. First of all, let’s talk about what is this product? This product is a resilient seated butterfly valve. What is its definition, working principle, advantages, and disadvantages? Where is the application? Definition of the resilient seated butterfly valve: A resilient seated butterfly valve is a valve that opens and closes by means of a spring-loaded disc. The disc is held closed by a spring, but when the valve is opened, the disc springs back open. This type of valve is commonly used in industrial applications because it requires little maintenance and can handle high pressures. Resilient seated butterfly valves are similar to poppet valves, which are also used in industrial applications. However, instead of having a ball that moves up and down inside the body to open and close the valve, resilient seated butterfly valves have a disc that moves up...
What is floating type ball valve? Floating ball valves can be divided into two categories: side-mounted body and top-mounted body according to the structural form of the valve body. The side-mounted valve body can be divided into integral, two-piece, and three-piece types. No matter what kind of structure, they must meet some basic principles. The basic principles that must be met by a floating ball valve are as follows: ①Stem should be installed backward, anti-blowout structure. This is ANSIB16.34 section 6.5.1.1, the structure of the valve stem should not rely on the packing gland fasteners to limit its position, to be precise, in the valve under pressure, the stem will not be due to the release of the stem sealing fasteners from the valve. This is the basic condition that must be ensured from the perspective of the safe use of the valve. ② anti-static structure is composed of a stainless steel ball and a spring, a group placed in the hole at the end of the stem to maintain contact with the ball; another group placed on the cylinder of the stem to maintain contact with the valve body so that the possible static electricity generated from the valve...
The structure form of a resilient seat seal gate valve: 1. Stem sealing structure The stem seal uses a three-way O-ring structure, as shown in Figure (a). The third O-ring reduces the pressure at the gland, and at the same time enables the pipeline to replace the upper two seals when there is medium pressure (replacing the stem seal and packing with pressure is dangerous, so this practice is not recommended). The O-ring seal construction can effectively reduce the opening and closing torque of the valve compared to the use of stuffing box construction [Figure (b)]. In the water supply industry is generally not recommended to use the form stuffing box structure, especially in the direct buried gate valve, is not allowed to use, because the stuffing box structure needs to be lubricated with outward seepage of water, and the stem seal can not use materials containing asbestos, etc. O-ring sealing structure on the stem processing accuracy and surface roughness accuracy requirements than the packing structure, otherwise there will be cut O-ring situation. The trapezoidal thread of the stem should be extruded, with high surface hardness and a small friction factor. The requirements for rubber material, process, and performance must...
As the electric valve is a combination of valve and electric device, so when the valve is determined how to correctly select the electric device is an important factor related to the actual use of whether it can meet the needs of the project. The selection of an electric device should not only consider the aforementioned working environment, electrical control, and general technical performance but also the comprehensive technical performance of the electric device should also be considered comprehensively. 1. The output torque and speed of the electric device The output torque value is one of the important technical parameters of the electric device, and it is also an important parameter to be selected in use. If the output torque of the electric device is too large or insufficient, it is not desirable to use the electric valve. Because in general, the electric device manufacturers need to test and adjust the output torque value when the product leaves the factory, which is relatively accurate. If you choose too much output torque margin, will make the electric valve has a great potential danger, once the control protection failure will easily cause damage to the valve (stem bending, valve body rupture) phenomenon,...
The slow-closing check valve is a special variety of check valves, which reduces water hammer pressure by slow-closing form. The slow-closing check valve has a variety of structure types, this article introduces three of them: two-stage slow-closing check valve, built-in cylinder damping slow-closing check valve, and water resistance controlled slow-closing check valve. First, two-stage slow-closing check valve This is a kind of side resistance slow-closing check valve with a double-cylinder damper, its structure principle is shown in Figure 1, the valve body is an ordinary swing check valve, but the rocker shaft of the valve flap is thicker and longer, wearing out the valve body outside, through the connection mechanism and the cylinder damper on both sides of the placement, the connection mechanism consists of the rocker arm, slide fork, and cross pin. When the pump stops, the valve flap is closed in two stages from the fully open position. Firstly, the flap falls down by its own weight, the cross pin of the rocker’s arm is lowered to the lowest point from high in the guide groove of the sliding fork, and the cylinder damper does not work, which is the fast closing stage, accounting for...
Definition of Check Valve: The check valve is a device that prevents the flow of liquid or gas in one direction only. It is used in plumbing and in industrial processes. The check valve is a one-way valve, which lets water drip through it but no air can go through it from below. The check valve also provides a non-return function because it has two discs with holes on each end and when you press down on one disc, it closes off any holes above it so there’s no way for air to get into your pipes even if you have some leaks! The check valve consists of a disc or flapper valve that closes when the fluid flow reverses (i.e., when water flows up instead of down). It works by allowing for a complete seal against backflow when opened so that anything trying to come up will not be able to pass through unless there’s pressure pushing hard enough against them all at once.” Working Principle of Check Valve The working principle of the check valve is simple: When the input pressure or flow exceeds a given value, the diaphragm will be compressed,...
Top 3 Things for selecting a electric Valve. In the pipeline project, the correct choice of electric valves is one of the conditions to meet the requirements of use. If the electric valve used is not properly selected, not only will affect the use, and can also bring adverse consequences or serious losses, therefore, in the design of pipeline engineering should be the correct choice of electric valves. 1. Working environment Electric valves should pay attention to the pipeline parameters, but also should pay special attention to the environmental conditions of their work, because the electric device in the electric valve is electromechanical equipment, and its work is greatly affected by its working environment. Usually, the electric valves are located in the following working environment: ① indoor installation or outdoor use with protective measures; ② outdoor open-air installation, wind, sand, rain, sunlight, and other erosion; ③ with flammable, explosive gas or dust environment; ④Humid tropics, dry tropics area environment; ⑤Pipe medium temperature up to 480℃ or more; ⑥The ambient temperature is below -20℃; ⑦easily flooded or immersed in water; ⑧ With radioactive materials (nuclear power plant and radioactive materials test equipment) environment; ⑨ on ships or docks (with...
What types of check valves are available? Introduction There are many different types of check valves available for a variety of applications. They all have unique features that make them ideal for specific applications. The following are the various types of valves. 1. Lift Check Valve A lift check valve belongs to a kind of automatic valve, its structure is generally composed of the valve body, valve cover, valve flap, sealing device, etc. Its main role is to prevent the backflow of media, prevent the pump and drive motor reversal, as well as release container media. Lifting check valve flap with the guide rod, the guide rod can be freely lifted in the valve cover guide hole. When the pipeline medium is in accordance with the specified direction (from left to right), the pressure below the valve flap exceeds the pressure above it, push the valve flap along the center line of the valve cover guide hole up, and the valve automatically open, so that the medium flow. If the fluid flows from right to left, that is, reverse inflow, the pressure above the valve flap is greater than the pressure below it, and the pressure difference...
Introduction: A resilient seat seal gate valve is also called a lift stem gate valve. A resilient seat valve is a type of gate valve, which uses a flexible rubber seat to seal the valve. Resilient seat valves are used in high-pressure applications and are also called rubber-faced valves. Resilient seat seal gates have a metal disc that opens and closes the flow path by using the force of a spring. The spring exerts pressure on the disc until it contacts the rubber seal. The spring is mounted on top of the disc and pushes down on it when required. When there is no pressure, the spring will push up against its stop. This type of seal uses a resilient material as a seal instead of packing or gaskets. Resilient materials are usually elastomers such as natural or synthetic rubber or plastic materials like nylon or polyethylene. They are designed to be soft enough to compress when pressure is applied but tough enough not to deform permanently from normal operating pressures. Resilient seat seals are commonly used in industrial settings where high pressures are present. They are not ideal for applications where there may be more than one opening in...
Introduction: Butterfly valves appear to be simple devices that are easy to use, but they have a wide range of applications in the industrial world. They are used for controlling the flow of liquids and gases through pipes, reducing pressure, and creating back-pressure situations. They come in many shapes and sizes and can be found almost anywhere there is an industrial facility or manufacturing plant. Butterfly valves last anywhere from ten years to over one hundred years depending on how they are maintained, what type they are made of and how often they get used. If butterfly valves are constantly being opened and closed, then it is possible that they could break within less than ten years. However, if they aren’t being used as much or properly maintained then their life span could increase substantially without any problems experienced during this period. It varies. It’s hard to say how long a butterfly valve will last for you because it depends on what you’re using the valve for. A butterfly valve is used in many industries and is used differently depending on which industry it’s being used in. For example, if you’re using a butterfly valve to control water flow through...