UF4 and UFR4 Series - Pressure Relief Valves

APV UF4 and UFR4 Pressure Relief Valves for Hygienic and Automated Processing

The APV UF4 and UFR4 Pressure Relief Valves are engineered to safeguard pumps and downstream process equipment by reliably opening in the event of a pressure spike. Designed for hygienic and aseptic applications (Aseptic Pressure Relief Single Seat Valves - UFMS4), these valves ensure consistent system protection and operational safety.

Beyond pressure relief, the UF4/UFR4 series offers enhanced control capabilities, allowing users to integrate the valve seamlessly into automated process systems. During CIP operations, the valve can also be actuated to ensure thorough seat cleaning and maintain top‑level hygiene.

Smart, robust, and automation‑ready, the UF4 Series delivers dependable performance for modern processing environments.

Optimum Cleanability

No dead spaces in the valve body
Full opening cross section available during cleaning (no seat lift stroke limitation)
3-A approved designs and compliance with EHEDG guidelines
All product-contact components made of AISI 316L / DIN EN 1.4404 stainless steel

Downtime Reduction and Serviceability

Enhanced control via proximity switches or control unit feedback for pressure relief events
Seal lifting function supports cleaning and minimizes downtime

Process Optimization

External over-pressure relief valve protects pumps and redirects excess pressure
Modulating cone provides smooth valve closure to prevent pressure hammers
Standardized valve sizes: DN 25 to DN 100 / ISO 1″ to 4″

Design and Upgrade Capability

Ball-shaped body with smooth passages—no sump or dome—for improved CIP cleaning
Standard seat lift actuator includes feedback switches
UF4/UFR4 inserts retrofit into existing UF3/UFR3 housings for simple upgrades
Wide pressure range achievable using four actuator configurations
Maintenance-free 5 years warranty UF4 actuator reduces service costs and downtime
Metal stop ensures defined seat seal compression, minimizing material stress
Compatible with CU4 and CU4plus control units for automated functionality

Actuator Warranty & Reliability

The actuator supplied with this valve is covered by a 5-year actuator warranty, or up to 1 million actuations, whichever comes first. Built with fully welded, sealed, maintenance-free construction, it eliminates internal servicing and reduces wear components to deliver long-term durability in demanding hygienic processing environments.

Key benefits include:

Maintenance-free operation with no internal servicing
Fewer spare parts and improved total cost of ownership
uptime and production continuity

Key Applications

The UF Series pressure relief valve is designed to protect installations against excess pressure

Dairy
Beverage
Brewery
Aseptic / sterile - UFMS
Chemical
Cleaning In Place (CIP)

Materials

Product wetted parts: 316L, 1.4404 (DIN EN 10088)
Non-Product wetted parts: 304, 1.4301 (DIN EN 10088)
Seal: EPDM, HNBR, FPM (FDA Compliant)
Internal Surface Finish: ≤32 Ra (≤0.8µ)

Sizes

1” – 4” O.D. Tube
DN25 – DN 100

Pressure Ratings

Operating Pressure UF4, UFR4 and UFMS: 0 – 10 BAR
UFHP: up to 40 BAR

Temperature Rating

EPDM, HNBR - 275ºF (135ºC), short time - 284ºF (140ºC)
FPM (not to be used for hot water) - 212ºF (100ºC)

Options

Wide range of housing/body configurationsm

Comprehensive range of valve housings are available to cover any requests.

Control Unit

The UF4/UFR4 valves can be delivered with a comprehensive range of CU4, CU4plus control units. The CU4, CU4plus are electrically provided to connect direct (DC) to a PLC system (CU4, CU4plus Direct connect) and to fieldbus protocols such as AS-i 3. Additionally, CU4plus also supports fieldbus protocol such as IO-link and AS-i 5.

Proximity switch

Proximity switches detect valve full open or close conditions.

Regulating (controlled) cone variant

Optimized control cone design provides slower, smoother valve closure to avoid water hammers.

Retrofit kits

Replacement inserts fits into existing UF3/UFR3 housings making an easy upgrade to next generation with improved features.
UF3 aftermarket parts (including actuators and seal kits) will remain available to service the legacy installed base. These parts are all available in the manual.