EN558-1 Series 15 Flanged Gate Valve PN25 NRS Functional Low Emissions

Valves Tested according EN1074-1,-2

Working Pressure:25kg/cm²
Shell Test Pressure:37.5kg/cm²

Seat Test Pressure:27.5kg/cm²

Media:Water,Neutral Oil
Working Temperature:0-52°C 100％

Fusion Bonded Epoxy Coating for Inner and Outside Surface

Flange Drilled According to EN1092 PN25
Size:DN50--DN300

Product Overview

The EN558-1 Series 15 Flanged Gate Valve PN25 NRS (Model 1003) is a high-pressure, long-pattern industrial gate valve engineered for functional reliability with low fugitive emissions. Designed to EN 558-1 Series 15 (DIN 3202 F5 long face-to-face) and rated PN25 with shell test at 37.5 bar, this valve combines robust ductile iron construction, wear-resistant internal components, precision stem sealing for emissions control, and a comprehensive FBE corrosion protection system. It is purpose-built for high-pressure water, neutral oil, and industrial fluid systems where environmental compliance and reliable long-term operation are equally important. Manufactured by Shandong Huaze Valve Co., Ltd. with over 25 years of specialized valve production, every Model 1003 is individually tested to EN 1074-1/-2.

The low-emissions design reflects a growing priority in industrial valve specification — controlling fugitive emissions from the stem seal and body joints to meet environmental regulations, protect operator health, and prevent product loss. The Model 1003 achieves this through a multi-tier stem sealing system with PTFE-impregnated packing, precision-machined stuffing box geometry, stainless steel gland fasteners that maintain consistent packing compression, and an EPDM body-bonnet gasket in a machined groove. For industrial plants under environmental permits and water utilities managing treated water containment, the low-emissions design provides documented compliance confidence.

Key Features

EN 558-1 Series 15 — Long Pattern, Proven Performance

The Series 15 / DIN 3202 F5 long face-to-face pattern provides a longer, more robust body casting with several engineering advantages for high-pressure service: a more gradual internal flow transition that reduces turbulence, cavitation risk, and localized erosion at the valve inlet; enhanced structural rigidity that better distributes pipe stress loads across the valve body; and additional internal volume for full gate travel clearance. At PN25 pressure levels, these long-pattern benefits become measurably significant — the extended body provides greater structural margin and flow stability compared to short-pattern alternatives.

Low Emissions Stem Seal — Environmental Compliance by Design

Fugitive emissions from valve stem seals are a significant environmental concern in industrial facilities — and a growing focus of regulation under ISO 15848 and local environmental permits. The Model 1003 addresses this with a precision-engineered stem sealing system: (1) PTFE-impregnated synthetic fiber braid packing provides low-friction, long-life sealing with chemical resistance across the full media range; (2) the stuffing box is machined to tight tolerances for uniform packing compression around the stem circumference; (3) stainless steel A2-70 gland bolts and gland flange maintain consistent packing load without corrosion-induced relaxation; (4) the packing is field-adjustable — if fugitive emissions standards tighten or packing settles over time, the seal can be restored without valve disassembly or process shutdown. For plants operating under ISO 14001 environmental management systems, the low-emissions design supports compliance documentation and audit requirements.

PN25 High Pressure — 25 Bar Working, 37.5 Bar Tested

Rated PN25 with shell hydrostatic test at 37.5 bar and seat tightness test at 27.5 bar — substantially exceeding PN16 class valves in both working pressure and safety margin. The higher pressure rating is achieved through GGG50 ductile iron's superior mechanical properties, optimized wall thickness design verified through casting simulation and hydrostatic proof testing, precision-machined bonnet joint geometry, and EN 1092-2 PN25 flange drilling. Applications include deep-well pumping station discharge headers, long-distance transmission mains with significant elevation profiles, high-rise building water supply systems, and industrial processes operating at elevated pressures.

Wear-Resistant Design — Built for High-Cycle Duty

Every component subject to sliding contact or wear is engineered for extended service life: the stem features precision-rolled stainless steel SS420/SS431 threads with a smooth, work-hardened surface finish that resists galling and wear; the bronze stem nut is inherently self-lubricating, maintaining low friction without external grease even under frequent cycling; the gate guide surfaces in the body are machined smooth to minimize wedge travel friction; and the FBE coating's hard, chemically resistant surface protects the internal flow path from erosion-corrosion. For valves in continuous or high-frequency operation — pump station duty, process batching, tank filling — this wear-resistant engineering directly extends the interval between overhauls.

NRS — Space-Efficient, Emissions-Friendly

The Non-Rising Stem design encloses the stem thread mechanism inside the valve body, where it is continuously lubricated by the line fluid and protected from external contamination. From an emissions perspective, the NRS configuration offers an inherent advantage: the stem does not translate through the packing during operation. In a rising-stem (OS&Y) valve, the stem slides through the packing with every cycle — a potential emissions pathway. In the NRS design, the stem rotates but does not translate, reducing packing wear and maintaining a more stable stem seal over the valve's operating life. Combined with the low-emissions packing system, this makes the NRS the preferred stem configuration for environmentally regulated installations.

Complete Material Integrity — No Weak Links

GGG50 ductile iron body and bonnet for strength and toughness; stainless steel SS420/SS431 stem for corrosion-free operation; high-strength bronze stem nut for self-lubricating durability; EPDM body-bonnet gasket and gland seals for reliable, long-life sealing; stainless steel A2-70 fasteners throughout to eliminate the rusted-bolt problem that plagues carbon steel fasteners in wet service; and 100% FBE coating at minimum 250 um DFT on all surfaces, individually spark-tested. Every material choice serves the functional reliability and low-emissions design philosophy — no compromises, no weak links.

Technical Specifications