Silent Check Valve Resilient Seat PN16 Reliable Ductile Iron Check Valve

Working Pressure:16kg/cm²
Shell Test Pressure:24kg/cm²
Seat Test Pressure:18kg/cm²

Media:Water,Neutral Oil
Working Temperature:0-52°C 1

00％ Fusion Bonded Epoxy Coating for Inner and Outside Surface

Flange Drilled According to EN1092 PN10,PN16
Size:DN50--DN300

Why Silent? — The Check Valve Noise Problem

In any pumped fluid system, the single loudest event in the normal operating cycle is the closure of the check valve. When a pump stops, forward flow decays — then reverses — and the check valve disc, travelling at full reverse-flow velocity, slams into the seat. The result is a pressure spike (water hammer) and an acoustic shock that propagates through the pipework, into building structures, and into the surrounding environment. Over years of daily cycling, this repeated impact fatigues pipe supports, loosens flange bolts, cracks concrete thrust blocks, and generates noise complaints from nearby residents. The Silent Check Valve Resilient Seat PN16 (Model 2212R) is engineered specifically to eliminate this problem — not to reduce it, not to manage it, but to design it out of existence.

Product Overview

The Model 2212R is a silent swing check valve with resilient EPDM seat, PN16 rated, DN50–DN300. Built on a GGG50 ductile iron body with EN1092 flanges, it combines three noise-suppression mechanisms into a single passive device: (1) a short-stroke swing arm that reduces disc travel distance, (2) an optimised lightweight disc that responds faster to flow decay, and (3) full EPDM-on-EPDM resilient seating that absorbs residual impact energy at the moment of closure. The result is a check valve that seals bubble-tight at 18 bar seat test pressure while generating negligible acoustic emission and negligible water hammer surge — suitable for installation directly adjacent to occupied buildings, in hospital plant rooms, under residential streets, and anywhere acoustic comfort is a specification requirement. Manufactured by Shandong Huaze Valve Co., Ltd. (ISO 9001, since 1998), each valve is individually hydro-tested, seat-tested, and closure-noise-checked.

The Engineering of Silence — Three-Layer Noise Suppression

Layer 1: Short-Stroke Swing Geometry — Less Distance, Less Velocity

In a standard swing check valve, the disc travels through a wide angular arc from the fully-open position (held there by forward flow) to the seated position. If reverse flow develops while the disc is still mid-swing, the disc is accelerated backwards by line pressure — it hits the seat at high velocity. The 2212R's short-stroke geometry reduces this arc: the disc, in its fully-open position, is closer to the seat than a conventional design. The closure travel distance is shorter, the closure time is faster, and the disc reaches the seat before reverse flow momentum can build. Less time in transit = lower velocity at contact = lower impact energy.

Layer 2: Optimised Disc Mass — Less Inertia, Faster Response

A heavy disc has more inertia — it resists starting its return swing when forward velocity decays, and once moving, it carries more kinetic energy. The 2212R disc is weight-optimised: the ductile iron core provides structural strength and the mass required to resist forward-flow flutter, but the overall disc mass is reduced compared to traditional designs. Lower mass means the disc begins closing the instant flow velocity drops below the hold-open threshold — no lag. And the reduced kinetic energy at contact means less energy for the seat to absorb, less energy transmitted as noise, less energy converted to pressure surge.

Layer 3: EPDM-on-EPDM Resilient Seat — Impact Absorption at the Contact Point

The final layer of noise suppression happens at the seating interface. The disc is fully encapsulated in EPDM; the seat ring is EPDM. When the EPDM disc face contacts the EPDM ring, the elastomer deforms microscopically, converting kinetic energy into heat within the EPDM matrix. There is no metal-to-metal contact path through which acoustic energy can propagate into the pipe wall. This is fundamentally different from a metallic seat valve, where the impact energy travels directly from disc through seat ring through body into connected pipework — ringing the entire pipe like a bell. The 2212R's EPDM seat breaks that acoustic circuit entirely.

The Cost of Noise — What a Loud Check Valve Really Costs

Water hammer and valve slam noise are often dismissed as "nuisance issues" — but they carry real costs that accumulate over the 20-30 year service life of a valve installation:

The premium for a silent check valve — typically a small fraction of the total installed pipework cost — pays for itself the first time it prevents one of these failures.

Key Features

Full EPDM Encapsulated Disc — Corrosion Barrier + Seal in One

The ductile iron disc core is completely encapsulated in EPDM — no exposed iron surface. This serves a dual purpose: (1) the EPDM skin is the primary corrosion barrier, protecting the disc from the service fluid; (2) the EPDM face is the sealing surface, mating against the renewable EPDM seat ring to form the bubble-tight closure. The encapsulation is vulcanised to the disc core — not a glued-on liner — ensuring a permanent bond that won't delaminate under thermal cycling or flow-induced vibration.

Renewable EPDM Seat Ring — Field Serviceable

The EPDM seat ring is a separate, replaceable component — not cast integrally into the body. If the seat face eventually shows wear after 15-20 years of service (a rare event given the low-impact closure), the ring can be replaced in the field by removing the bonnet, extracting the worn ring, and seating a new one. The body remains in the pipeline — no cutting, no welding, no shutdown beyond isolating the valve.

GGG50 Ductile Iron — Absorbs Shock That Cracks Cast Iron

EN-GJS-500-7 ductile iron: 500 MPa tensile strength, 320 MPa yield, minimum 7% elongation. While the 2212R dramatically reduces slam forces, the body must still withstand the full pipeline hydrostatic test pressure and occasional surge events. Ductile iron absorbs transient pressure spikes through elastic deformation — it flexes and returns — whereas gray cast iron fractures when stressed beyond its brittle limit. For a check valve in a pumped system where surge is always a possibility, the GGG50 body is an insurance policy against catastrophic body failure.

Stainless Steel SS304 Hinge Assembly — Corrosion-Free Motion for Life

The swing arm and hinge pin are both stainless steel 304 — the only moving assembly in the valve. In a check valve, the hinge is the single point of failure: if it corrodes, seizes, or wears, the disc cannot close, and the valve becomes a permanently open conduit for reverse flow. SS304 arm running on a SS304 pin — submerged in water or neutral oil — will operate freely for the full service life of the valve without corrosion, without binding, and without lubrication.

100% FBE Internal & External Coating — No Bare Iron Anywhere

Fusion bonded epoxy at 250 um DFT minimum, electrostatically applied and oven-cured on every surface — internal flow path, bonnet interior, external body. Spark-tested at 3 kV for holiday detection. FBE creates an impermeable barrier between the iron and the environment. For check valves that sit idle and water-filled for extended periods — standby pump lines, fire water systems, seasonal irrigation — this internal protection is critical. Without it, internal corrosion creates tuberculation that can physically obstruct the disc's movement and prevent the valve from closing when it's finally needed.

Zero Leakage at 18 Bar — Backflow Prevention You Can Count On

Every 2212R is seat-tested at 18 bar (1.1 × PN16 nominal). The EPDM-on-EPDM seal achieves and holds zero leakage — not trace, not Rate A, not "acceptable" — zero. In drinking water systems, backflow from a leaking check valve into the public supply is a contamination event. In building services, a dripping check valve on a basement pump line can flood a plant room. In district cooling, a leaking check valve on a standby chiller recirculates return water and ruins system efficiency. Zero leakage is not a specification luxury — it is an operational requirement.

Silent Check Valves vs Other Noise Solutions

Materials of Construction

Technical Data

Applications

• Pump Discharge — Noise-Sensitive Locations: Pump stations under residential streets, inside apartment building basements, adjacent to schools or hospitals. Where the sound of a slamming check valve becomes a community relations problem.
• Building Services — MEP Plant Rooms: Hotels, hospitals, office towers, shopping malls. HVAC chilled water and condenser water pump discharge. Noise travels through building structure — a silent check eliminates one major noise source.
• District Cooling / Heating Networks: Parallel chiller/boiler pump headers. A leaking check on a standby unit recirculates return water, destroying the designed delta-T and system efficiency. Zero leakage maintains hydraulic separation.
• Drinking Water Booster Stations: Backflow prevention in potable water distribution. Zero-leakage closure protects public health. EPDM is WRAS-approved for drinking water contact.
• Fire Protection Systems: Jockey pump and main fire pump discharge. Frequent cycling on jockey pumps makes silent closure essential for longevity. Fire pumps must start reliably — a seized check valve on a fire pump discharge is a life-safety failure.
• Irrigation & Golf Course Pumping: Pump stations in parks, golf courses, and landscaped areas near residential property. Pump cycling noise complaints are a recurring operational headache — a silent check removes the loudest transient.
• Sewage Pumping Stations (Clean Water Side): On the clean water side of sewage pump stations (seal water, wash water), where the station may be located adjacent to residential property. The 2212R handles clean water/neutral oil only — for raw sewage, consult our flap valve range.

Quality Assurance — Every Valve Tested

• 100% Shell Hydrostatic Test — 24 bar, 60 sec, zero leakage — every valve
• 100% Seat Tightness Test — 18 bar, EN 1074-3, zero leakage — every valve
• 100% Disc Movement Test — Short-stroke swing, full angular travel, no binding — every valve
• 100% Closure Noise Audit — Auditory assessment of closure event — every valve
• 100% EPDM Encapsulation Inspection — Visual + adhesion check on every disc
• 100% FBE Coating DFT Verification — min 250 um, all surfaces — every valve
• 100% Spark Test — 3 kV holiday detection, full coated surface — every valve
• 100% Flange Dimensional Check — EN1092 PCD, bolt hole diameter, flange thickness — every valve
• EN 10204 3.1 Material Certificates available on request

Ordering Information

About Shandong Huaze Valve Co., Ltd.

Established 1998 in Qingdao, China. ISO 9001 certified manufacturer with 100–200 employees, 300 containers annual production capacity, and USD 5–6 million annual turnover. Huaze produces a comprehensive range of pipeline valves and fittings for water, wastewater, irrigation, fire protection, and industrial applications: Gate Valves (DIN 3352 / EN 558, BS 5163, SANS 664), Swing Check Valves (Resilient Seat, BS 5153 Metallic, Silent Metallic, Silent Resilient), Air Valves, Globe Valves, Flap Valves, Fire Hydrants, and Y Strainers. All products are factory-tested and shipped from Qingdao Port. Huaze exports to 30+ countries across Europe, Middle East, Africa, Southeast Asia, and South America.