Flow Verification & Failure Detection for Semiconductor Chemical Dosing
A pump can be commanded on while nothing is actually being delivered. Here's the real hardware that closes that gap.
Same boundary as the rest of this cluster: facilities-side dosing verification, never wafer-contact UHP chemical delivery. See the flagship guide for the full explanation.
"Pump is running" and "chemical is being delivered" are two different claims. A PLC run signal confirms the first. It says nothing about a ruptured tube, a failed diaphragm, a lost prime, or a blocked discharge. On a facilities dosing point — neutralization, scrubber recirculation, cooling tower treatment — that gap can run for hours before a downstream sensor (pH, ORP, conductivity) finally shows the drift, by which point the process has already been out of spec the whole time.
Four Layers, Not One Signal
Command
The control system tells the pump to run at a given rate. This confirms a signal was sent — nothing more.
Tube/Diaphragm Failure Detection
Blue-White's TFD (peristaltic) senses tube rupture via a closed-circuit conductivity sensor inside the pump head — chemical bridging both sensors trips it. DFD (diaphragm) detects failure at the DiaFlex® PVDF diaphragm on most CHEM-FEED models. Both are built-in, patented, standard — not an add-on.
Independent Flow Verification
The MS6 ultrasonic flow meter measures actual delivered flow (10–10,000 mL/min) independently of the pump's own command signal, with isolated 4-20mA and pulse outputs and configurable high/low/range triggers.
Alarm / Failover
TFD trips a relay switch on detection — pump auto-shuts-off and signals external equipment (backup pump, SCADA, alarm). MS6's configurable triggers do the same for a flow-rate or total-volume deviation. The protective layer only matters if it actually stops or reroutes the process, not just logs an event.
How TFD Actually Detects a Tube Failure
TFD works via a closed-circuit conductivity sensor built into the pump head — two sensor points that a ruptured tube's leaking chemical bridges to close the circuit. It's engineered to trigger on conductive chemicals (chlorine, acids, soaps) while disregarding plain water, so rain, condensation, or routine wash-down doesn't cause a false trip. On detection, the pump shuts off automatically and energizes a relay switch that can signal a backup pump, SCADA system, or alarm — the failure gets contained and reported, not just logged after the fact.
Frequently Asked Questions
How does Blue-White's TFD (Tube Failure Detection) actually detect a tube rupture?
TFD uses a closed-circuit conductivity sensor built into the pump head. When a tube ruptures, the leaking chemical bridges two sensors and closes the circuit — the pump shuts off automatically and energizes a relay switch that can signal a backup pump, SCADA system, or alarm. It's designed to react to conductive chemicals (chlorine, acids, soaps) while disregarding plain water, so rain, condensation, or wash-down doesn't cause a false trip.
Does a metering pump's "running" signal prove chemical was actually delivered?
No. A run signal confirms the pump received a command — it doesn't confirm chemical moved. A pump can be commanded on while its tube or diaphragm has failed, its suction has lost prime, or its discharge is blocked, and the run signal alone won't show any of that. Independent flow verification (measuring actual delivered flow, not commanded flow) is the layer that catches it.
What is the real difference between TFD and DFD?
TFD (Tube Failure Detection) is built into Blue-White's FLEXFLO peristaltic line and detects chemical leaking from a ruptured tube inside the pump head. DFD (Diaphragm Failure Detection) is built into most CHEM-FEED diaphragm models and detects failure at the DiaFlex® PVDF diaphragm. They protect the two different pump technologies' specific failure modes — a peristaltic pump has no diaphragm to fail, and a diaphragm pump has no tube.
Is flow verification only relevant for the highest-consequence dosing points?
It's most valuable there, but the failure mode it protects against — command without delivery — doesn't announce itself by consequence level. A low-consequence dosing point that silently stops dosing can still drift a process out of spec for hours before anyone notices without an independent flow signal.
Close the gap between commanded and confirmed dosing
Ready to buy or need a fast answer? Call, text, or email James directly — (559) 395-5500 · [email protected].