YDK SIGNAL BUTTERFLY VALVE | MODEL KBF(WF)-16

In modern fire protection design and building management systems (BMS), monitoring the OPEN/CLOSED status of isolation valves on sprinkler lines and pump stations is a prerequisite for ensuring that water is always available in an emergency. The YDK signal butterfly valve, Model KBF(WF)-16, is an optimal replacement for the signal gate valve: it offers flexible operation through a gearbox with handwheel, and integrates a limit monitor switch that instantly transmits an electrical signal to the fire alarm control center.

Key features of the YDK signal butterfly valve KBF(WF)-16

The core feature that allows the YDK signal butterfly valve, Model KBF(WF)-16, to meet the strict requirements of fire protection standards (TCVN 3890 / NFPA) is the electrical signal unit integrated on top of the gearbox:

• Travel limit monitor switch: The sensor unit uses a dry contact system (NO/NC). When the valve is FULLY OPEN, the contacts keep the circuit in its normal state. As soon as the handwheel is moved away from the open position (even by just a few degrees), the switch immediately changes the contact state.
• Instant alert to the fire protection control panel: The switching signal (supervisory signal) is sent immediately to the central fire alarm control panel or the BMS. A valve that has been closed secretly or by human error is detected right away, preventing the risk of no water at the sprinkler heads.
• Waterproof protective housing: The signal unit is enclosed in a watertight, electrically insulated housing that resists moisture, mold, and electromagnetic interference. This design allows the YDK signal butterfly valve to be installed and used reliably in damp technical rooms and basement pump stations.

Installation procedure for the YDK electrical signal butterfly valve KBF(WF)-16

Step 1: Prepare materials and tools, and inspect before installation

• Valve inspection: Check that the epoxy paint surface, the disc, and the EPDM/NBR rubber liner are free of cracks, damage, or dirt. Turn the handwheel 1–2 turns to confirm that the gearbox drive operates smoothly.
• Electrical inspection: Use a multimeter (VOM) to test the continuity of the dry contact unit (limit switch) on top of the valve, to identify the NO (normally open) and NC (normally closed) terminals correctly.
• Auxiliary materials: A steel pipe section pre-welded with two standard PN10/PN16 or JIS 10K flanges, a set of threaded rods/clamping bolts, nuts, and washers matching the Z x ød size, plastic-coated steel-core flexible conduit, and cable glands.

Step 2: Clean the flanges and align the pipeline gap

• Surface cleaning: Use a wire brush and a clean cloth to remove all weld slag, rust, and grease from the two flange faces that contact the valve.
• Concentric alignment: Check the parallelism and concentricity of the two pipeline flanges. The gap between the two flanges must be about 5 mm – 10 mm greater than the valve face-to-face length (L), so that the valve can be inserted easily without scratching the rubber liner.

Step 3: Set the butterfly disc to a slightly open position

• Open the signal butterfly valve disc slightly, at an angle of 10° to 20°: Use the handwheel to turn the disc a little away from the fully closed position.
• Technical note: Absolutely DO NOT leave the valve FULLY CLOSED when inserting it between the two flanges. If it is fully closed, the edge of the stainless steel disc will protrude beyond the rubber liner, and when the flanges are pressed together it will jam, tear the rubber liner, or warp the disc.

Step 4: Position the valve and install the wafer clamping bolts

• Position the valve: Carefully place the YDK signal butterfly valve in the gap between the two flanges, aligning the positioning lug holes with the flange bolt holes.
• Insert the bolts: Pass the threaded rods / bolts through the flange holes and the positioning lug holes on the valve body. Hand-tighten the nuts to hold the valve steady at the center of the pipeline.

Step 5: Tighten the bolts in a cross pattern and check mechanical operation

• Cross (X) pattern tightening: Use a torque wrench to tighten the nuts in diametrically opposite pairs (X pattern). Tighten gradually and evenly over several passes until the two flanges press tightly against the rubber liner of the valve.
• Check the mechanical stroke: Turn the handwheel to open and close the valve fully from 0° to 90° about 2–3 times. Watch the position indicator on the gearbox to make sure the disc moves smoothly, without rubbing against or catching on the inner wall of the flange/pipe.

Step 6: Connect the signal wiring to the control panel

• Protective cable routing: Run the signal cable (2-core or 4-core depending on the design) through plastic-coated steel-core flexible conduit, and tighten the cable gland firmly into the monitor switch box to prevent water from entering.
• Contact wiring: Wire the dry contact unit (NO/NC) strictly according to the project’s fire protection design drawings.
• Insulation and closing: Tighten the terminal screws and close the cover of the limit switch housing securely.

Step 7: Test run and signal acceptance

• Power up supervision: Enable the supervisory mode on the central fire alarm control panel.
• Test operation: With the valve FULLY OPEN, turn the handwheel in the CLOSE direction by about 1–2 turns.
• Confirm the result: Check whether the control panel immediately issues a water supply interruption warning signal. Turn the valve back to the FULLY OPEN position and check at the panel whether the alarm state clears automatically.

Some notes when installing the YDK electrical signal butterfly valve

• Allow for a straight pipe section: To avoid turbulence that makes the disc vibrate, install the signal butterfly valve on a straight section of pipe, at least 3 – 5 pipe diameters (3D – 5D) away from elbows, bends, and tees.
• Signal cable wiring: The signal cable from the monitor switch to the control panel must be run inside waterproof plastic-coated steel-core flexible conduit. Check continuity (resistance measurement) before energizing for the test run.

Why choose the YDK signal butterfly valve for your piping system?

For fire protection, HVAC, and similar systems, the YDK signal butterfly valve delivers outstanding economic and installation benefits:

• Saves 40% – 50% of system weight: Compared with a signal gate valve of the same size (such as DN150 or DN200), the butterfly valve is much lighter, reducing the load hung from the gypsum ceiling. This in turn lowers the cost of pipe clamps, hanger rods, and sway braces.
• Optimized installation space: The wafer-type face-to-face length is very short, allowing easy installation in tight spaces such as technical shafts, close to walls, or next to concrete beams in basements.
• Optimized investment cost: The YDK signal butterfly valve is considerably cheaper than the YDK signal rising stem gate valve of the same brand. Contractors can optimize their material budget while still meeting 100% of fire protection standards.

Genuine YDK signal butterfly valve supplier in Vietnam

An Phu Thanh is the official distributor of YDK industrial valves and pipe fittings in Vietnam. With more than 17 years of experience working alongside projects large and small across the country, we are committed to delivering a comprehensive solution that is optimal in both investment cost and real-world operating performance.

• Large warehouse capacity: The full size range from DN50 to DN300 is in stock at our Ho Chi Minh City warehouse, meeting urgent delivery schedules for projects.
• Complete legal documentation: All products leaving the warehouse come with a Certificate of Origin (CO), a Certificate of Quality (CQ), a Packing List, and a VAT invoice.
• Pricing policy for contractors: Attractive commercial discounts based on project volume, plus price-holding support for projects built in multiple phases.

To receive a quotation for the YDK signal butterfly valve (Model KBF(WF)-16) together with the catalogue spec sheet, please contact An Phu Thanh via Hotline / Zalo: 0946 729 913 for the fastest support!