I. Product Overview:

FJ41Y Throttle Cut-off Drain ValvePre-filtered double-sealed throttle stop drain valves are a type of drain valve featuring reliable sealing, corrosion resistance, long service life (several orders of magnitude longer than general throttle and stop valves), high degree of standardization and generalization, excellent sulfur resistance, and significant energy-saving effects. This valve is an ideal choice for applications in the oil, natural gas, petrochemical, metallurgical, and power systems where zero leakage and long service life are critical for drain sections.

II. Working Principle:

1. Normally Closed: The valve disc is firmly sealed against the valve seat's boss, creating a hard seal. Simultaneously, the soft seal embedded in the valve disc is pressed tightly against the seat end face, forming another seal. The dual-seal structure ensures zero leakage for the valve. Additionally, due to the balanced holes in the valve disc, the valve experiences less force and torque during opening and closing.

2. Slow-pressure State: When the bottom of the valve disc leaves the sealing surface of the valve seat, due to the bottom surface of the valve disc being close to the bottom edge of the cage-type sleeve opening groove, at this moment, the valve disc forms a seal with the inner diameter of the cage-type sleeve. There is no direct emptying to relieve pressure, thus achieving a mitigation effect.

3. Throttling State: The valve disc base carbide leaves the valve seat and further opens, creating a primary throttling with the small valve disc. The high-speed fluid passes through the pressure-reducing throttling and directly flows towards the small valve disc and valve sleeve groove to form a window flow channel, achieving a secondary throttling. Since the valve sleeve window edge is a throttling surface, when the high-pressure medium directly washes the throttling channel, the bottom end of the valve disc generates eddies due to the change in medium direction, mitigating the direct impact of the medium on the valve disc. Consequently, the valve seat seal also avoids direct medium impact. Additionally, due to the conical shape of the valve disc sealing surface, it can blow away dirt and impurities on the valve seat sealing surface, protecting the sealing surface and thereby extending the valve's service life.

4. Full Open Position: In the fully open state, the valve is fully open, leading to the entire valve being in a full venting condition. The fluid resistance within the cold gate is reduced, shortening the venting time and enhancing the valve's venting efficiency.

Section 3: Structural Features:

1. This valve is a throttle, cut-off, and venting product, featuring a cage-type throttle mechanism with multi-stage throttling effects. It offers distinct throttling performance, reliable sealing, and easy operation and maintenance.

2. Valves feature dual sealing (hard and soft) for reliable sealing, with hard alloy coatings that are more resistant to air flow erosion and wear. The dual sealing ensures zero leakage under high-pressure gas medium conditions. The valve has a long service life.

3. The valve seat sealing surface is cone-sealed, which is conducive to cleaning the dirt adhering to the sealing surface of the valve itself.

4. The valve disc features balanced holes, with a piston-type seal that ensures stable operation under full open/close pressure differences. It is easy to open and close, with minimal torque required.

5、Throttle Cut-off Valve, Drain ValveThe throttle section with a double-acting throttle valve simultaneously performs throttling and cutoff (sealing for zero leakage) functions. The throttling section is separated from the sealing surface to reduce the erosion of the seal by air flow.

6. The double-acting throttle check valve also features multi-stage throttling capability, with a large throttling pressure difference, suitable for throttling and cutoff under high pressure conditions.

7. The packing utilizes a V-shaped packing structure with self-sealing capabilities, requiring no adjustment and offering extremely easy opening and closing. The packing box is equipped with an auxiliary sealing grease injection structure, ensuring reliable sealing performance of the valve packing.