Schubert & Salzer – Type 4000 – Check Valve

Overview

The Schubert & Salzer Type 4000 is a robust stainless steel check valve designed for backflow prevention in demanding industrial applications. Available in nominal sizes from 3/8″ to 3″, it handles gases, vapors, and fluids — including aggressive and high-temperature media — with a maximum allowable differential pressure of 580 psi (size-dependent).

All wetted components are constructed of stainless steel with PTFE seating as standard, making the Type 4000 well-suited for corrosive process environments. Multiple body styles, connection types, and seal materials are available to meet application-specific requirements.

Features & Benefits

• All wetted parts stainless steel (316L body; 316Ti/301 interior parts) — suitable for aggressive and corrosive media
• PTFE seating seal standard — chemical resistance across a wide range of process fluids
• Compact design — minimizes installation space requirements
• Low cracking pressure — approximately 3 psi standard; optional 1.5 psi with reduced spring tension
• Wide temperature range — -40°F to +392°F standard; optional up to 428°F
• Multiple body configurations — angle seat, rectangular (angle), and flanged bodies available
• Multiple connection options — NPT thread, BSP/Whitworth thread, welding ends, tri-clamp, and flange connections (DIN EN 1092-1 / ANSI 150)
• EU and UKCA Declarations of Conformity

Technical Specifications

• Nominal sizes: 3/8″ – 3″ (angle seat body); 1/2″ – 2″ (angle/rectangular body); 1/2″ – 3″ (flanged body)
• Body material: Stainless steel 316L
• Interior parts material: Stainless steel 316Ti / 301
• Seating seal: PTFE standard; optional EPDM, NBR, FKM (Viton), PEEK, EPDM (FDA), PTFE with 25% glass fiber
• Maximum allowable differential pressure (PTFE/PEEK seat): 580 psi (3/8″ – 1-1/2″); 365 psi (2″ – 3″)
• Maximum allowable differential pressure (FKM / EPDM / NBR seat): 230 psi (all sizes)
• Cracking/lifting pressure: ~3 psi standard; ~1.5 psi with reduced spring option
• Operating temperature: -40°F to +392°F standard; optional up to 428°F
• Media: Gases, vapors, fluids
• Connections: NPT thread, BSP/Whitworth thread, welding ends (ISO, DIN 11850, socket weld), tri-clamp (inch), flanges per DIN EN 1092-1 and ANSI 150
• Approvals: EU Declaration of Conformity; UKCA Declaration of Conformity
• Pressure limitation for dangerous gases: PS (psi) × DN (inch) / 1.75 < 1000 per Pressure Equipment Directive 97/23/EG (Category I)

Applications

• Backflow prevention in gas, vapor, and fluid process lines
• Aggressive and corrosive media handling
• High-temperature process applications (up to 392°F standard; up to 428°F optional)
• Food, beverage, and pharmaceutical processes (EPDM FDA seal option)
• Chemical processing and industrial fluid systems
• Steam and condensate systems
• Tri-clamp sanitary piping configurations

Type 4000 Accessories

• Repair kits (seals) – Replacement sealing sets available; order using the “R” designation in the Type 4000 ordering number system

Documentation