Soft seal gate valve (elastic seat seal gate valve) is a key improved valve that uses non-metallic elastic materials (such as rubber) as the overall sealing pair on the basis of traditional gate valves. The gate is usually wedge-shaped, with rubber covering the exterior as a whole; The sealing surface of the valve body is machined to match the sealing surface of the gate plate. When the valve is closed, the gate descends and the rubber sealing surface tightly adheres to the valve body sealing surface under pressure, forming an elastic seal. This design gives it a significant advantage over traditional metal sealed gate valves, with excellent zero leakage sealing performance; Small closing torque, easy to operate; Rubber can absorb vibrations and compensate for certain deviations; And it has strong adaptability to fluids and is not easily blocked. However, its application is also limited by the characteristics of rubber materials and is not suitable for working conditions such as high temperature, high pressure, sharp particles, or highly corrosive media. The soft seal gate valve produced by Kaiweixi has become the mainstream shut-off valve in urban water supply networks, building water supply systems, and general fluid transportation fields due to its excellent sealing and economy, especially suitable for clean water media with strict sealing requirements. Resilient Seated Gate Valve (Elastic Seat Gate Valve)

Hard sealed gate valve refers to a gate valve made of metal materials (body seal or alloy steel butt welding, hard alloy butt welding) for both the valve seat and gate sealing surface. Its sealing relies on the rigid contact of high-precision matching between metal sealing pairs, representing the high-performance and high reliability direction of gate valves. Compared with soft sealed gate valves, the core advantage of hard sealed gate valves lies in their excellent durability: they can withstand higher temperatures and pressures, are less prone to wear, have stronger adaptability to media containing particles, impurities, or erosive properties, and have a longer service life. Although its sealing level usually meets national standards on the basis of double-sided sealing, the difficulty of achieving zero leakage is higher than that of elastic sealing. According to structural optimization, modern hard seal gate valves often adopt designs such as elastic gate plates or parallel double gate plates, using medium pressure to assist in sealing, in order to improve sealing effect and reduce operating torque. The hard seal gate valve produced by Kaiweixi Valve is a key cutting equipment in harsh industrial environments such as petroleum, natural gas, chemical, power plants, and high-temperature and high-pressure steam pipelines. It is suitable for water, steam, oil products, and various corrosive media.

The five standard gate valves of API, JIS, DIN, GOST, and EN have differences in connection size, pressure rating, material specifications, and inspection requirements, but the core structure and function are the same. API American standard gate valve (ANSI/API 600/602/6D): marked in inches (NPS) and pounds (Class), with flange standard ASME B16.5/B16.47. Its design, materials, and testing standards (such as API 598/6D) are extremely strict, especially in terms of fire resistance and sulfur resistance requirements. It is a globally recognized standard in the petroleum, natural gas, and refining industries, representing high reliability and performance. JIS Japanese standard gate valve (JIS B207/208): uses nominal diameter DN (JIS caliber) and pressure rating K (such as 10K, 20K). Its standards have been widely applied in the industrial fields of Japan, East Asia, and some Southeast Asia, and share commonalities with some old Chinese standards (JB). DIN German standard gate valve (DIN 3352/3356): adopts DN and PN pressure ratings, and the flange standard is DIN series with rigorous design and precise material system. It has gradually been integrated into EN standards. EN European standard gate valves (EN 1984, EN 12516) are modern European standards that have been unified and coordinated. GOST Russian standard gate valve (GOST 9698, 5762): adopts DN and PN pressure ratings, but its size, material, and testing standards are self-contained and have poor interchangeability with Western standards. It is a mandatory standard that must be followed by Russia, CIS countries, and some Eastern European markets.

Knife type gate valve is a special type of valve designed with a clamp, which is widely used in industries such as chemical, papermaking, sewage treatment, and mining due to its compact structure, low flow resistance, and reliable sealing. Its core structure consists of a valve body, a knife shaped gate, a U-shaped sealing ring, and pneumatic/electric actuators. When the valve is opened and closed, the thin and sharp gate cuts the medium like a knife, effectively preventing fibers, particles, or viscous materials from depositing and blocking inside the valve, ensuring smooth pipeline flow. The valve adopts a dual sealing design: the U-shaped elastic sealing ring ensures the main seal, while the adjustable sealing strip embedded in the valve body further enhances the sealing reliability. The knife shaped gate valve produced by Zhejiang Shanliu Valve Technology can not only be used for rapid cutting, but also is particularly suitable for regulating and throttling media such as slurry and powder.