Flow Switches in Pharmaceutical CIP Lines

Overview

Pharmaceutical and biotech facilities require flow switches that meet strict hygienic standards. The PEECO Model NP-T Sanitary Flow Switch is designed specifically for these applications, featuring a stainless steel external bellows assembly, Tri-clamp (Tri-clover) connections, and an optional electropolish finish.

Key Sanitary Requirements

• Tri-clamp connection: Allows tool-free disassembly for inspection and cleaning. Standard 1½″ and 2″ sizes available.
• 316L stainless steel wetted parts: Low carbon content resists sensitization during SIP steam cycles.
• Electropolish finish: Ra ≤ 0.5 µm internal surface finish minimizes bacterial adhesion and facilitates drainage.
• No dead legs: External bellows design keeps all sensing components outside the flow path, eliminating crevices.
• CIP/SIP compatibility: Rated for caustic wash solutions (NaOH) and steam up to 300°F.

Typical CIP Sequence Integration

In a typical CIP sequence, the flow switch is wired to the CIP skid PLC to confirm that wash solution is flowing through the circuit before the timer starts. This prevents the CIP controller from logging a "clean" cycle if a valve failed to open or a pump did not start. The SPDT micro-switch output connects directly to a digital input on the PLC.