Alfa Laval Unique RV-ST
The Alfa Laval Unique RV-ST Regulating Valve is the third generation of the Alfa Laval single-seat regulating valve designed to meet the highest process demands of hygiene and safety. Built on a well-proven platform form an installed base of more than a million valves. It is ideal for high-volume, hygienic liquid processing applications that require precision control of flow rate or pressure.
The RV-ST has a vast range of Kv-values to fit customers exact needs. 1½” – 4″ sizes come with a plug seal to also function as a shut-off valve, where 1″ sizes do not have a plug seal.
With an integrated IP converter and push-and-play setup, the Unique RV-ST regulating valve is able to meet the highest process demands for hygiene and safety.
Hygienic corrosion-free regulating valve
The Alfa Laval Unique RV-St is an intelligent hygienic regulating valve that safely and effectively controls process flows with Kv-values between 9 and 246m³/hour. It is designed for a wide range of fluid handling duties, such as metering, blending, weighing and filling system duties. in the food and beverage, brewery, biotech and pharmaceutical and chemicals industries. Corrosion-free features, such as tapered stainless steel stems, ensure product safety according to EHEDG (European Hygienic Engineering and Design Group) guideline.
Advanced electro-pneumatic controller
The Unique RV-ST regulating valve comes with an advanced electro-pneumatic controller with an integrated IP converter. This offers superior control of product flow by combining different pressure drops and stroke lengths. It also features a contact-free analog position sensor, which measures the position of the valve spindle, and a standard Profibus DP-V1 or optional DeviceNet communications interface. Analogue or binary feedback is available as options.
Easy push-and-play regulating valve setup
With a push of a button, the Alfa Laval Unique RV-ST regulating valve automatically calibrates itself so that it is fully operational.
Reliable, easy to maintain.
Built on the proven SSV (Single Seat Valve) Platform, which has an installed base of more than one million valves, the Alfa Laval Unique RV-ST UltraPure offers the same reliability, safety and ease of maintenance. It offers protection class IP65 and IP67 for tough process environments.
A regulating valve with maximum flexibility
It uses the same few moveable components, spare parts and maintenance tools and procedures as Alfa Laval SSV valves. Using the upgrade kit available, it is possible to upgrade older regulating valves with the new control unit. The new control unit also supports rebuild of the actuator from normally closed (NC) to normally open (NO) and vice versa.
Product Benefits
- Intelligent hygienic regulating valve
- Easy push-and-play regulating valve setup
- Maximum flexibility
Construction
The Alfa Laval Unique RV-ST regulating valve with integrated IP converter is a second-generation single-seat valve. It features:
- Broad selection of stainless steel tapered valve stems
- Unique actuator with electro-pneumatic process controller for precise control of product flow
- Rugged, long-lasting plastic stem bushings that eliminate metal-to-metal galling
- Standard EPDM plug seal used by the entire Unique valve series
The stems are threaded to the actuator shaft, which eliminates the coupling between the stem and the actuator, thereby ensuring proper alignment. Bushings at end of the actuator cylinder support the stem and ensure perfect alignment.
Operating principle
The Alfa Laval Unique RV-ST regulating valve can be controlled from a remote location by means of a digital electro-pneumatic process controller.
The control unit comes in two versions: with or without display. It has an analogue 4-20 mA communication interface and is protected according to IP66 and IP67.
Options
- Male parts or clamp liners in accordance with required standard
- Product wetted seals in HNBR or FPM
- Maintainable actuator
- External surface finish blasted
- Optional plug seal: HNBR or FPM
Concept Unique
RV-ST is the third generation of Alfa Laval single seat regulating valves designed to meet the highest process demands of hygiene and safety. Built on a well-proven, platform from an installed base of more than one million valves, it is ideal for high volume, sanitary liquid processing applications where precision control of flow rate or pressure is required.
Working principle
The valve is remote-controlled by a digital electro-pneumatic process controller. It has few and simple moveable parts which results in a very reliable valve.
Technical Data
Max. product pressure: . . . . . 10 bar (1000 kPa).
Min. product pressure: . . . . . Full vacuum.
Temperature range: . . . . . . . . 10°C to +140°C (EPDM).
Air pressure: . . . . . . . . . . . . 5 – 7 bar (500 to 700 kPa).
Positioner data
Material: . . . . . . . . . . . . . . . PPS, stainless steel
Cover: . . . . . . . . . . . . . . . . PC
Seals: . . . . . . . . . . . . . . . . EPDM
Supply voltage: . . . . . . . . . . 24 VDC +/- 10%
Working temperature: . . . . . . 0 to 55 °C
Push-in fittings: . . . . . . . . . . ø6mm or 1/4 inch
Protection class: . . . . . . . . . IP65 and IP67
Position detection module: . . . Contact-free, wear-free
Communication: . . . . . . . . . . Analog
8692 Positioner – Top control with display
Setpoint setting: . . . . . . . . . 0/4 to 20mA and 0 to 5 5/10V
Output resistance: . . . . . . . . 0/4 to 20 mA: 180? 0 to 5/10V: 19?
Power consumption: . . . . . . < 5W
Cable gland: . . . . . . . . . . . . 2xM16x1,5 (cable-ø10mm)
Max. wire diameter . . . . . . . . 1.5 mm2
Physical Data
Product wetted steel parts: . . .1.4404 (316L)
External finish . . . . . . . . . . . .Semi-bright (blasted)
Internal finish . . . . . . . . . . . .Bright (polished), internal Ra < 0.8 µm
Other steel parts: . . . . . . . . .1.4301 (304)
Plug seal: . . . . . . . . . . . . . .EPDM
Other product wetted seals: . .EPDM (standard)
Other seals: . . . . . . . . . . . . .NBR
8694 Positioner – Basic control without display
Setpoint setting: . . . . . . . . .0/4 to 20mA
Output resistance: . . . . . . . .180?
Power consumption: . . . . . .< 3,5W
Cable gland: . . . . . . . . . . . .2xM16x1,5 (cable-ø10mm)
Max. wire diameter . . . . . . . .1.5 mm
Standard design
Designed to deliver years of reliable performance, it features a broad selection of stainless steel, tapered valve stems along with the Unique actuator to ensure an outstanding degree of precise product control. Rugged and long-lasting plastic stem bushings eliminate metal-to-metal galling. The stems are threaded to the actuator shaft, eliminating the coupling between the stem and the actuator, thereby ensuring proper alignment. The plug seal is a standard seal used for the entire Unique Series. Bushings at the end of the actuator cylinder support the stem and ensure perfect alignment.
Other valves in the same basic design
– Sanitary Unique Single Seat
– Standard valve – Reverse acting valve
– Long stroke valve
– Manually operated valve
– Aseptic valve
Options
- Male parts or clamp liners in accordance with required standard
- Product wetted seals in HNBR or FPM
- Maintainable actuator
- External surface finish blasted
- Optional plug seal: HNBR or FPM
How to Use Data to Select Valve Size
After the Kv factor for a specific application has been calculated, locate the factor on the following page. Choose the curve closest to the 50% stroke. Using the above example, refer to the chart on the previous page you will find that the Kv factor (49) is marked on the chart. You will find that a 2 inch valve crosses 1 Kv curve, 2½ inch 1 curve, 3 inch 3 curves and 4 inch 3 curves. The correct valve size to use is 2 inch because Kv 49 crosses the curve closest to the optimum operating point 50%. Alternatively the 4 inch valve is also close to the 50%.
