YDK Flanged Y-Strainer | Model: KGL-16

In water supply and drainage, fire protection, Chiller, and industrial piping systems, dirt, gravel, welding slag, and mechanical debris are major causes of control valve diaphragm damage, pump impeller jamming, or flow meter failure. In such cases, a “shield” is needed to protect all downstream equipment. The YDK Flanged Y Strainer, Model KGL-16, serves this purpose. The product retains solid contaminants inside the filter screen, preventing them from entering the piping system.

Detailed Construction of YDK Y Strainer, Model KGL-16

The YDK Y Strainer is a passive mechanical filtration device with a “Y”-shaped design that helps reduce pressure loss compared to straight-type strainers. At the same time, contaminants settle at the bottom of the filter chamber, making periodic cleaning easy.

Detailed Construction Table of Y Strainer Model KGL-16

Dimensions of YDK Flanged Y Strainer

Installation Notes for YDK Y Strainer

Installation Position in the Piping System

The Y strainer must be installed upstream of equipment that needs protection from debris and contaminants, such as:

• Before the pump (pump suction): protects the pump impeller from jamming and wear caused by debris and sediment.
• Before control valves, pressure reducing valves (PRV), and solenoid valves: prevents valve jamming caused by contaminants entering the opening/closing mechanism.
• Before the flow meter: ensures measurement accuracy and prevents sediment buildup from causing measurement errors.
• Before heat exchangers, chillers, and AHUs: protects heat exchanger tubes from blockage.
• At the inlet of fire protection systems (before the fire pump and at the water supply inlet to the sprinkler system): commonly used in Vietnamese fire protection system designs to protect sprinkler heads and alarm valves from blockage caused by pipe scale and rust deposits.

Fluid flowing through the valve branch is forced to pass through the stainless steel filter screen. Dirt and contaminants larger than the mesh openings are retained inside the filter chamber, while clean water continues flowing through the system.

Y Strainer Installation Direction

• The strainer must be installed in the correct direction according to the DIRECTION arrow printed on the valve body. Flow must enter from the main pipeline into the “inclined branch” of the Y, pass through the filter screen, and then exit through the “straight branch”.
• If installed in the reverse direction: the fluid will not pass through the filter screen properly, resulting in ineffective filtration and potentially causing abnormal pressure loss or dislodging the filter screen.

Installation Orientation

• Installation on a horizontal pipeline: the filter chamber (the Y-shaped tail section where the valve cover is located) must point downward or be inclined downward so that contaminants settle properly into the chamber. This also makes it convenient to remove the valve cover for cleaning without draining the entire pipeline.
• Installation on a vertical pipeline: the flow should preferably move upward, with the Y-shaped tail positioned horizontally to facilitate removal of the filter screen when cleaning is required.
• Note: Avoid installing the Y-shaped tail facing upward, as this makes cleaning difficult and causes contaminants to accumulate in the reverse direction, resulting in faster blockage.

Y Strainer Installation Clearance

• Sufficient clearance should be provided to remove the valve cover and pull out the filter screen during maintenance. Do not install it too close to a wall or other equipment that may obstruct access.
• It is recommended to install gate/ball valves at both ends, upstream and downstream of the Y strainer, so that the strainer can be isolated for cleaning or filter replacement without draining the entire system. This is a common design recommendation in M&E drawings in Vietnam.

YDK Y Strainer Cleaning Procedure

– Step 1: Prepare and Isolate the System

Close the gate/ball valves at both ends, upstream and downstream of the Y strainer, to isolate the pipeline section. If isolation valves are not available, release the pressure and shut off the entire system supply.

– Step 2: Release Pressure and Drain Remaining Fluid

Open the drain valve, if available, or slowly loosen the valve cover bolts to release all residual pressure and fluid remaining inside the filter chamber, preventing splashing when the cover is completely removed.

– Step 3: Remove the Valve Cover

Use a wrench to remove all bolts securing the valve cover to the valve body in a symmetrical (cross/star) sequence to prevent the flange surface from becoming misaligned or warped. Lift the valve cover away.

– Step 4: Remove and Inspect the Filter Screen

Remove the stainless steel filter screen from the chamber. Check the level of sediment buildup, rust, tears, or deformation. If the screen is torn or perforated, replace it immediately and do not reuse it.

– Step 5: Clean the Filter Screen

Wash it with pressurized water or compressed air in the reverse direction of flow to push contaminants out. For stubborn deposits, a soft brush or a suitable cleaning solution may be used (avoid chemicals that can corrode stainless steel).

– Step 6: Inspect the O-ring

Inspect the O-ring (NBR/EPDM) for hardening, cracks, deformation, or other damage. If there are signs of aging, replace it with a new gasket before reassembly to ensure proper sealing.

– Step 7: Reassemble and Tighten the Bolts

Reinstall the filter screen in the correct direction inside the chamber, install a new O-ring if necessary, replace the valve cover, and tighten the bolts in a symmetrical (cross/star) sequence with even tightening force to prevent flange misalignment and leakage.

– Step 8: Slowly Open the Valves and Check for Leakage

Slowly open the isolation valves to gradually pressurize the pipeline. Observe the valve cover area and connections for the first few minutes to detect any leakage early. If the system remains stable, return it to normal operation.

Note: For clean water systems, periodic inspection every 1–3 months is recommended. For systems with high levels of sediment or circulating water (chillers, cooling towers), inspections may be required more frequently, every 2–4 weeks. In many M&E systems, a differential pressure gauge can also be installed upstream and downstream of the Y strainer. When the differential pressure exceeds the allowable threshold, this indicates that the filter screen is clogged and requires immediate cleaning rather than waiting for the scheduled maintenance interval.

The above covers the main information related to the YDK Y strainer. If you need consultation or a detailed quotation, please contact An Phu Thanh directly via Hotline/Zalo: 0946 729 913. Our team is always ready to support you.