The Alfa Laval SB Membrane Sampling Valve is a hygienic membrane sampling valve that places a stretchable membrane seal in direct contact with the product flow. The sample drawn is genuinely representative of what is running in the line or tank, rather than a fraction from a stagnant dead leg.

How does the membrane seal prevent contamination during sampling?

The membrane acts as a stretchable plug seated directly at the process interface. When closed, the plug physically occupies the sample port, blocking the pathway between the external environment and the process fluid. This design ensures there is no cavity behind the seal where residual product can pool and degrade. When actuated, the membrane deflects to open a defined flow path, returning to its sealed position immediately on release. This plug-and-deflect action ensures the only contact point is the membrane itself, removing the need for flush volumes to displace secondary barriers.

SIP capability reinforces this sterile design. Before and after each sampling cycle, the valve body is sterilized in place using alcohol or steam to eliminate contamination from the sample port and outlet path. This makes the valve suitable for applications where microbiological integrity of the sample is critical, such as fermentation monitoring, pasteurisation verification, or ingredient quality checks.

SIP sterilization: what temperatures and media are supported?

The valve handles a process temperature range of +1 °C to +130 °C. For SIP sterilization by dry steam at 2 bar, the maximum sterilization temperature is 121 °C. Both silicone and EPDM elastomers are supplied with the valve, giving operators the flexibility to select the membrane material best suited to their process chemistry and sterilization regime without requiring a separate order at the point of purchase.

Mounting options for tanks, pipelines, and threaded connections

Three body types address standard installation scenarios. Type T mounts directly into a tank wall; Type P welds directly into a pipeline and is available for 1″ pipe, DN25, and ø12 mm tube; Type S uses 3/8″ BSP socket mounting for threaded installations. All body types support manual and pneumatic actuation, and the standard outlet connections use clip-on hose pieces for secure attachment. Swagelok outlet connections are available as an option where the installation demands a permanent fitting.

Wetted part materials and surface specification

All product-wetted steel components are manufactured from 1.4404 (AISI 316L) and supplied with 3.1 material certification. Non-wetted structural parts use 1.4307 (AISI 304L). The combination of corrosion-resistant alloy steel, certified traceability, and food-grade elastomers meets the material expectations of hygienic process industries. The standard valve ships with one clip-on closing cap, both silicone and EPDM membrane options, and pipe outlet connections, making it ready for installation in most standard applications.