YDK Non-rising Stem Supervisory Gate Valve | Model KNX-16S

In modern fire protection systems, monitoring the OPEN/CLOSED status of shut-off valves is a mandatory requirement under TCVN 3890. However, in confined installation spaces such as underground technical valve chambers, basement service boxes, or locations where fire protection pipelines run close to concrete beams, rising stem valves can interfere with the ceiling as the stem rises. The YDK non-rising stem signal gate valve (Model KNX-16S) provides a technical solution to both challenges: maximizing installation space efficiency while continuously transmitting electrical monitoring signals to the central fire alarm control panel.

Construction of YDK Non-Rising Stem Signal Gate Valve | Model KNX-16S

The construction of the KNX-16S non-rising stem signal gate valve is similar to the YDK rising stem signal gate valve series. The product consists of the following main components:

• Valve Body & Bonnet: Cast from GGG50 Ductile Iron to withstand high pressure and mechanical bending forces, with an electrostatic epoxy coating for corrosion protection.
• Gate / Wedge: The GGG50 Ductile Iron core is cast as a single piece and fully coated with elastic EPDM rubber to achieve Class A sealing performance.
• Stem Nut: Manufactured from Brass for excellent wear resistance, allowing smooth raising and lowering of the gate while minimizing thread stripping and mechanical jamming.
• Gasket: Made of EPDM rubber with excellent heat resistance and elasticity, installed between the bonnet flange and valve body.
• Valve Stem: Manufactured from stainless steel SS420 with precision-machined threads, providing high torsional strength and corrosion resistance when continuously immersed in the fluid medium.
• Gland: Cast from GGG50 Ductile Iron, securely holding the valve stem vertically and compressing the stem sealing gasket.
• Monitoring Bracket Structure: Made of Stainless Steel, ensuring that the monitoring switch assembly remains securely positioned and protected against corrosion in humid environments.
• Handwheel: Robustly cast from GGG50 Ductile Iron and coated with epoxy to resist dirt accumulation.

Electrical Signal Transmission Mechanism of YDK Non-Rising Stem Signal Gate Valve

Although the threaded stem operates completely inside the valve body, keeping the overall valve height fixed, the monitoring sensor is specifically designed to work with the YDK non-rising stem signal gate valve:

• Limit Switch Box: The sensor assembly is integrated with the valve bonnet. When the handwheel is turned to open or close the valve, the switch detects the movement of the gate through the rotation of the stem and changes the state of the dry contacts (NO/NC).
• Alarm Signal Transmitted to the Central Panel: As soon as the valve is partially closed from the FULLY OPEN position (after only 1–2 turns of the handwheel), the switch immediately sends a Supervisory Signal to the fire alarm control panel. This enables operators to immediately identify where the firefighting water supply has been interrupted without having to visually observe the movement of the valve stem.

Recommended Installation Locations & Installation Notes for Signal Gate Valve

• Common Installation Locations: Confined technical service boxes, underground fire protection valve chambers, or fire protection pipelines running along basement corridors where the suspended ceiling is positioned close to concrete beams.
• Signal Wiring Installation: Since the valve may be installed in confined spaces or underground chambers, the electrical signal cable from the Limit Switch to the fire alarm control panel must be protected inside waterproof plastic-coated flexible steel conduit to prevent moisture-related issues and false signal short circuits.
• Operation: Although the rising and lowering movement of the stem cannot be visually observed, operators can still check the valve status by monitoring the indicator lights on the central fire alarm control panel or checking the number of handwheel turns.

YDK Non-Rising Stem Signal Gate Valve Price | Model KNX-16S

The price of the YDK non-rising stem signal gate valve depends on factors such as product size, order quantity, delivery location, and other conditions:

• Pipeline Size (DN50–DN300): Larger valves from DN200 and above require a greater quantity of GGG50 ductile iron casting material and higher-load transmission components, resulting in a significant price difference compared with smaller valve sizes.
• Exchange Rate Fluctuations & Volume Discounts: The price of officially imported materials may vary depending on the customs clearance period. For large-volume orders or complete material packages for an entire project, An Phu Thanh applies commercial discounts, allowing customers to receive preferential pricing and optimize their initial equipment and accessory investment budget.
• Coordination & Transportation Costs: Depending on the delivery location in Hanoi, Ho Chi Minh City, other provinces nationwide, or overseas, we will determine the most efficient transportation solution to help contractors optimize their budgets.

To receive the most accurate quotation for YDK non-rising stem signal gate valves based on the exact quantity in your project estimate, together with the complete Catalogue file, please contact An Phu Thanh directly via Hotline / Zalo: 0946 729 913. Our team is always ready to respond and provide you with a detailed quotation as soon as possible!