Products
View some of our proven products from leading manufacturers, selected to deliver reliable solutions and supported across the UK.
The FLT93S and FLT93F Flow and Level Switches are robust, industrial thermal flow switches designed for reliable flow, no-flow and level detection across a wide range of gas, liquid and slurry applications.
Both models are built on the proven FLT93 platform, offering two distinct sensor designs to suit different process conditions. The FLT93S features a heavy-duty, rugged sensor construction, making it particularly well suited to liquids, slurries and challenging process environments. The FLT93F incorporates a fast-response sensor design, making it ideal for gas applications and processes where rapid detection of flow changes is critical.
Using thermal dispersion technology, the FLT93S/F provides accurate and repeatable switching performance without moving parts. This eliminates mechanical wear, helping reduce maintenance requirements while improving long-term reliability in demanding industrial environments.
The FLT93S/F range is highly configurable, with a wide selection of materials, process connections and sensor lengths available to suit specific applications. Wetted parts can be supplied in 316 stainless steel, Hastelloy or Titanium, ensuring compatibility with aggressive, corrosive or high-temperature media.
Designed for use in hazardous and safety-critical environments, the FLT93S/F offers fully adjustable alarm set points, with options for ATEX certification and SIL2 rating. This makes them suitable for use in Safety Instrumented Systems (SIS) and critical process protection applications.
- Thermal flow switches for flow, no-flow and level detection
- Two sensor designs to suit different applications:
- FLT93S – heavy-duty sensor for liquids, slurries and harsh environments
- FLT93F – fast-response sensor for gas applications and rapid detection
- Suitable for gas, liquid and slurry processes
- No moving parts for reduced maintenance and improved reliability
- Available in 316 stainless steel, Hastelloy and Titanium wetted parts
- Fully adjustable alarm set points with dual relay outputs
- ATEX certified and SIL2 rated options available
- Process temperatures up to +450°C
- Custom sensor lengths and configurations available
- Screwed or flanged process connections
Over 45 Years in Operation
1000's of UK Installations
Supporting 100's of UK Sites
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Allison Engineering supports projects from early-stage selection through to supply, commissioning and long-term support. For customers, that means not just choosing a product, but getting the right solution for the application.
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Supply & Commissioning
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Support & Optimisation
Teams providing calibrations, servicing, maintenance, training and ongoing support to keep systems performing accurately and reliably over time.

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