First, why the double seat valve is easy to oscillate when working at a small opening degree. For a single core, when the medium is a flow-open type, the valve has good stability; when the medium is a flow-closed type, the stability of the valve is poor. The double seat valve has two valve cores, the lower valve core is closed, and the upper valve core is open. This way, when the valve is operated at a small opening, the flow-closed valve core can easily cause the vibration of the valve. This is the double seat valve. The reason why it cannot be used for small opening work.
Second, why the double seal valve can not be used as a shut-off valve The advantage of using a two-seat valve core is the force balance structure, allowing a large pressure difference, and its outstanding drawback is that the two sealing surfaces can not be in good contact at the same time, resulting in large leakage. If it is artificially and forcibly used in cutting off occasions, it is obviously not effective, and even if it is made with many improvements (such as double sealed sleeve valve), it is not desirable.
Third, what direct stroke control valve anti-blocking performance is poor, angular stroke valve anti-blocking performance straight trip valve spool is vertical throttling, and the medium is the level of flow in and out, the valve cavity flow path will inevitably turn inverted, so that the valve The flow path becomes quite complex (shape is like inverted "S" type). In this way, there are many dead zones, which provide space for the sedimentation of the media and, over time, cause blockages. The direction of throttling valve throttle is the horizontal direction, the media flow into the horizontal outflow, easy to take the unclean media away, while the flow path is simple, the medium precipitation space is also very small, so the angle valve anti-blocking performance is good.
Fourth, why the straight stroke valve stem smaller It involves a simple mechanical principle: large sliding friction, rolling friction is small. The stem of the linear valve moves up and down, and the packing is pressed slightly. It will pack the valve stem tightly and generate a large return difference. For this reason, the valve stem is designed to be very small, and the filler is often a PTFE filler with a small friction coefficient so as to reduce the return difference, but the problem is that the valve stem is thin, it is easy to bend, and the filler life is short. To solve this problem, the best way is to use the trip valve stem, which is a quarter-rotor type valve. Its valve stem is 2 to 3 times thicker than the linear valve stem, and the long-life graphite filler is used. The stem rigidity is Well, long filler life, the friction torque is small, the difference is small.
5. Why is the cut-off pressure difference of the angle stroke valve larger?
The cut-off pressure difference of the angular stroke valve is larger because the resultant force generated by the medium on the valve plug or the valve plate generates a very small torque on the rotating shaft, so that it can withstand a large pressure difference.
6. Why does the service life of the lined plastic butterfly valve and fluorine-lined diaphragm valve is short due to the desalinated medium?
Demineralized water contains low concentrations of acids or bases that are highly corrosive to rubber. Corrosion of rubber is manifested as swelling, aging, and low strength. The use of rubber-lined butterfly valves and diaphragm valves are all poor in their effect. The reason is that rubber is not resistant to corrosion. The rear rubber-lined diaphragm valve was improved to be a fluorine-lined diaphragm valve with good corrosion resistance, but the diaphragm of the fluorine-lined diaphragm valve could not withstand folding up and down and was broken, causing mechanical damage and shortening the life of the valve. The best way now is to treat the special ball valve with water. It can be used for 5 to 8 years.
Seven, why cut off the valve should try to use a hard seal cut off valve requires a lower leakage, the better, the soft seal valve leakage is the lowest, of course, the cutting effect is good, but not wear and poor reliability. From the double standards of small leaks, sealing and reliability, soft seal cutting is not as good as hard seal cutting. Such as full-featured ultra-light control valve, sealed and piled with wear-resistant alloy protection, high reliability, leakage rate of 10 to 7, has been able to meet the requirements of the shut-off valve.
Eight, why sleeve valves instead of single and double seat valves do not fulfill the wishes of the sleeve valves of the 1960s, and they were widely used at home and abroad in the 1970s. The proportion of sleeve valves in petrochemical plants introduced in the 1980s was relatively large. At that time, many people believed that sleeve valves could replace single and double seat valves and become second-generation products. Until now, this is not the case. Single-seat valves, double-seat valves, and sleeve valves have all been used equally. This is because the sleeve valve only improves the throttling type, stability and maintenance better than single seat valve, but its weight, anti-blocking and leakage indicators are consistent with single and double seat valves. How can it replace single and double seat valves? What? Therefore, they can only be used together.
Nine, why is the selection more important than the calculation? Comparing calculation and selection, the selection is much more important and more complex. Because the calculation is just a simple formula calculation, it is not the accuracy of the formula itself, but the accuracy of the given process parameters. There are many items involved in the selection, and careless selection will result in improper selection. This not only results in a waste of manpower, material resources, and financial resources, but also results in unsatisfactory results. It brings with it certain problems in use, such as reliability, longevity, and operation. Quality and so on. - Sanjing Valve Technology Division
Magnetic Track accessories are add-ons associated with magnetic track systems that enhance and customize the functionality and performance of magnetic tracks. These accessories can provide more flexibility, convenience and ornamentation, making the magnetic track system more practical and versatile.
Magnetic rail accessories include many types of accessories and enhancements. For example, magnetic track attachments can be various connectors, connecting pieces, or connecting blocks used to connect different segments of magnetic track together to form a longer track system. These attachments can precisely connect the rails, ensuring their stability while simplifying the installation process.
In addition to connection accessories, magnetic track fittings can also include luminaires and lighting components. By adding adjustable lighting fixtures to the magnetic tracks, a softer and more diverse lighting effect can be provided to the space. These lighting accessories can be moved or replaced as needed to help create the ideal light atmosphere.
In addition, magnetic fixture accessories can also include various decorative elements, such as hooks, decorative cover plates, wire management kits, etc. These accessories can not only add to the aesthetics of the track system, but also provide additional practical functions, such as hanging ornaments, hiding wires, etc.
In short, magnetic track accessories are add-ons associated with magnetic track systems to enhance, customize and enhance the function and appearance of the track system. They offer more flexibility, convenience and decorative options, enabling magnetic track systems to adapt to a variety of needs and design styles, and bring a better experience and beauty to interior spaces.Magnetic Track Systems,Magnetic Rail Accessories,Magnetic Track Attachments,Magnetic Track Fittings,Magnetic Fixture Accessories
SHENZHEN LITEHOME OPTOELECTRONIC TECHNOLOGY CO., LTD. , https://www.szlitehomelight.com