Brass Horizontal Check Valve

Brass horizontal swing check valve：Springless, gravity-operated swing check valve; the valve disc is opened by the medium's thrust force, while closure is achieved by backflow combined with the disc's own weight; very low pressure loss; recommended for horizontal installation; vertical pipelines are only suitable for upward medium flow; vertical downward flow installation is prohibited; due to the delayed closure of the valve disc during shutdown, there is a risk of water hammer; not suitable for pump systems with frequent start-stop cycles.

Spring-loaded vertical check valve：Built-in reset spring; compatible with any installation orientation; spring-assisted rapid closing to mitigate water hammer; drawback: the spring introduces an additional pressure drop; the spring may fail due to long-term fatigue; suitable for applications involving frequent pump start/stop cycles or environments requiring water hammer protection.

Yuanlun brass horizontal swing check valve is spring-free gravity-operated non-return valve. It adopts hinged swing-disc structure, no internal spring component. Forward-flow medium pushes swing disc open; when flow stops or reverses, swing disc drops by its own weight plus reverse-flow momentum to press tightly against valve-seat, blocking medium back-flow.

PN16 nominal pressure-rating, DN15-DN50, working-temperature 5℃-90℃. Rated-flow pressure drop ΔP＜0.1 bar. Critical limitation: Only for clean non-corrosive medium without solid particles; forbidden for media containing sand, scale, fiber impurities. Installation priority for horizontal pipelines (hinge pin keep upward); vertical piping only permits medium upward flow; vertical down-flow installation is strictly prohibited, which will cause disc cannot close and continuous back-flow. This valve has no spring, slow closing characteristic, will generate water-hammer risk for systems with frequent pump emergency shutdown. If anti-water-hammer performance is required, select spring-loaded / slow-closing check-valve instead.

Suitable for domestic water-supply, HVAC heating-chilled-water clean-medium piping-systems.

Important note: Installation recommended to be completed by qualified plumbing / HVAC technicians. Must follow body-cast flow-direction arrow; horizontal install hinge pin on top; vertical mounting only for upward medium flow; never install for vertical down-flow. Pipeline must be thoroughly flushed before commissioning to eliminate solid impurities.

• Zero-Energy Gravity-Driven Operation: Fully self-actuating by medium flow and swing-disc gravity, no spring, no external power source required.
• Ultra-Low Flow Resistance: Optimized full-bore swing-disc runner, pressure drop ΔP ＜0.1 bar under rated flow condition, reduces system pumping energy consumption.
• Less Failure Points (Spring-Free Design): Eliminate spring fatigue, aging and breakage failure mode; fewer wearing components, lower routine service demand.
• Optimized For Horizontal Pipeline Service: Hinge-up horizontal installation gives most reliable gravity-assisted disc-sealing performance for horizontal piping circuits.
• Rapid Reverse-Flow Cut-Off: Swing-disc drops rapidly once flow reverses under correct mounting orientation, blocks back-flow volume under design working-condition.

Important limitation：It is NOT suitable for vertical-down-flow installation. Under vertical-down-flow condition gravity will hold swing-disc open, check-valve completely loses non-return function, resulting in persistent back-flow and severe water-hammer hazard. Slow closing feature brings water-hammer risk for frequent pump-trip systems.

Specifications

• Main Components & Function

• Operating Principle

Brass horizontal swing check-valve is spring-free gravity-driven non-return valve：

1. Forward-flow: Medium flows following body-cast arrow direction. Fluid momentum pushes hinged swing-disc to swing open, medium passes through full-bore runner with very low pressure-drop.
2. Flow-stop / reverse-flow: When forward-flow diminishes or back-flow occurs, swing-disc falls down under self-weight plus reverse-flow impact, closely presses onto valve-seat metal sealing-face, cuts-off back-flow to realize non-return protection.
3. Installation orientation critical warning：
4. Horizontal installation: hinge pin must keep at top, to ensure disc can freely drop by gravity onto seat.
5. Vertical installation：ONLY allow medium flow upward. Gravity assists disc closure when flow stops.
6. Strictly prohibit vertical-down-flow mounting：Gravity will hold swing-disc hanging open; valve cannot close, complete loss of back-flow prevention function, lead to back-flow, chattering vibration and destructive water-hammer phenomenon.
7. System risk reminder：No-spring gravity closing causes delayed disc seating on pump sudden shutdown, will produce water-hammer pressure surge. Frequent pump-trip system should choose spring-assisted or slow-closing check-valve.

Operating reminder: Incoming medium must be clean. Solid impurities may wedge between swing-disc and valve-seat, resulting in permanent back-flow leakage.

• Residential & Commercial Clean-Media Water-Supply Systems

Use-case: Back-flow prevention for domestic cold-hot-water piping circuits with relatively stable flow and infrequent pump shutdown. Project value: Ultra-low pressure-drop spring-free design reduces pumping energy consumption for continuous water-supply loops.

• HVAC Heating & Chilled-Water Hydronic Systems

Use-case: Non-return protection for heating / chilled-water circulating loops using clean glycol-mixed anti-freeze liquid. Project value: Suitable for steady-running HVAC circuits; Not recommended for pump frequent emergency-trip loops due to inherent water-hammer risk.

Application exclusion:

Not for vertical-down-flow pipeline layout.

Not for medium containing sand, rust scale, solid particle, fiber impurities.

Not for steam, strong-corrosion chemical / petrochemical medium.

Not recommended for systems with frequent pump sudden shutdown (water-hammer risk; select spring-loaded check-valve instead).

• Pre-Installation Check

1. Confirm valve DN-size, thread-spec match pipeline port; carefully read body-cast flow-direction arrow.
2. Confirm installation layout: prefer horizontal installation (hinge pin upward); vertical only medium upward flow; reject vertical-down-flow scheme.
3. Inspect brass valve-body, swing-disc, hinge pin and valve-seat; reject cracked, deformed, swing-disc jamming-risk components.
4. Thoroughly flush entire pipeline before valve installation to remove welding slag, rust scale and solid particles; impurity will jam disc-seat sealing pair and cause back-flow leakage.
5. Prepare qualified PTFE-tape for thread joint sealing.

• Installation Steps

1. Wind PTFE-tape 3-5 clockwise-turns on mating pipeline thread port.
2. Mount valve into pipeline, strictly align body-cast flow-arrow with actual medium flow direction.
3. Horizontal installation：make sure hinge pin position on the top of valve-body to guarantee free gravity drop of swing-disc.
4. Vertical installation：only adopt medium upward-flow arrangement. Do NOT install for downward-flow.
5. Apply wrench torque only on valve-body hex flats. Do not apply force to bonnet / hinge assembly to avoid hinge-pin deformation and swing-disc jamming.
6. After mechanical assembly finished, perform system water-filling and pressure-testing.
7. Test valve non-return performance: cut-off forward-flow, inspect whether back-flow occurs; check thread-joint external-leakage.

• Important Installation Notes

1. Installation recommended for qualified plumbing / HVAC technicians.
2. Never install for vertical-down-flow piping; swing-disc cannot close, valve loses all non-return function.
3. Hinge pin must be placed upward under horizontal installation condition.
4. Pipeline complete flushing is mandatory before commissioning; solid particles will jam swing-disc and cause permanent reverse-leakage.
5. This spring-free swing check-valve has slow-closing property; frequent pump emergency-shutdown system shall use spring-assisted / slow-closing check-valve to mitigate water-hammer hazard.
6. Standard brass variant only for clean neutral non-corrosive liquid; steam / corrosive / particle-laden medium requires customized material / different valve-type.

Routine-Maintenance Suggestion

• Visual inspection for thread-joint external-leakage and back-flow phenomenon: Quarterly during system operating-season
• System overhaul period: disassemble valve, clean swing-disc, hinge-pin and valve--seat sealing-face, inspect swing-disc free swing action: Annually
• If sealing-face is scratched or hinge assembly permanently deformed: recommend complete valve replacement.

When purchasing brass horizontal swing check-valve: confirm DN-size, thread-spec, PN16 pressure-rating. Clarify project piping layout：this valve fit horizontal (hinge-pin-up) OR vertical upward-flow;strictly cannot be deployed for vertical-down-flow. Medium must be clean neutral non-corrosive liquid without solid particles. For pump frequent-trip, anti-water-hammer requirement, choose spring-loaded / slow-closing check-valve instead of this spring-free swing-type. Steam / corrosive medium need custom-made variant.

Yuanlun brass horizontal swing check valve is PN16 spring-free gravity-driven brass non-return valve, DN15-DN50 size-range. Hinged swing-disc structure, no internal spring; ultra-low pressure-drop ΔP＜0.1 bar at rated-flow. Valid installation: horizontal with hinge-pin upward or vertical pipe medium upward-flow; vertical-down-flow installation strictly prohibited. Only for clean non-corrosive water/glycol liquid without solid particles. Slow-closing characteristic; water-hammer risk exists for systems with frequent pump emergency shutdown (spring-loaded check-valve recommended for those cases). Widely-applied for residential-commercial water-supply and HVAC heating-chilled-water steady-flow hydronic-systems. Sample-order supported for pre-project-evaluation, 15-day standard lead-time for worldwide plumbing-HVAC distributors and engineering-contractors.

Zhejiang Yuanlun Valve Co., Ltd. was founded in 2006, formerly known as Yuhuan Guohong Valve Co., Ltd. It is located in Yuhuan, Zhejiang Province, known as the "Valve Capital of China". After nearly two decades of stable development, Yuanlun Valve is a professional manufacturer for HVAC valves integrating R&D, production and sales. Our product portfolio covers floor heating systems, air-conditioning systems, domestic water valves, including ball valves, thermostatic valves, manifolds, check valves, stop valves, filter valves, angle valves, pipe fitting s, corrugated pipes and other series.