British Rototherm Industrial Thermometers and Pressure Gauges

Heavy-duty industrial thermometers, thermowells, pressure gauges, and chart recorders from British Rototherm for process and energy installations.

British Rototherm BH3 and BH2 Heavy Duty Bimetallic Thermometers

Heavy-duty bimetallic thermometers from British Rototherm deliver continuous temperature monitoring across harsh industrial environments. Model BH3 features a versatile Any Angle rotatable dial joint, while Model BH2 provides a rigid stem with axial or radial process thread connections.

Versatile Any Angle rotatable joint enabling three hundred sixty degree dial positioning
Wetted components and protective housing fabricated from grade AISI 316 stainless steel
Dial diameters of 100 and 160 mm covering measurement spans from -50 to +500 degrees Celsius
Robust mechanical construction resisting severe process pulsation and mechanical vibrations

British Rototherm Pt100 RTD Sensors and Mineral Insulated Thermocouples

Industrial platinum resistance thermometers Pt100 and thermocouple assemblies from British Rototherm deliver precision thermal detection in severe environments. Dense mineral insulation sleeves shield inner detector wires against oxidation, moisture ingress, and thermal degradation.

Precision platinum Pt100 sensing elements meeting Class A and B tolerance under IEC 60751
Thermocouple calibrations K, J, N, and T housed in heat-resistant stainless and Inconel sheaths
Semi-flexible mineral insulated probe sheaths allowing bending around narrow pipe pathways
Heavy duty terminal connection heads accommodating integral 4-20mA smart signal transmitters

British Rototherm Solid Machined Thermowells to ASME PTC 19.3 TW

Bar-stock and fabricated thermowells from British Rototherm isolate temperature sensors against high process velocity and severe fluid pressure. Engineering calculations verify vortex shedding resonance limits under ASME PTC 19.3 TW to prevent dynamic fatigue failures in pipeline assets.

Threaded, flanged, socket weld, and Van Stone loose flange mechanical installation designs
Mandatory vortex shedding frequency calculations conforming to ASME PTC 19.3 TW guidelines
Machined from round bar in AISI 316L, 321, Hastelloy, Monel 400, and grade titanium alloys
Rigorous non-destructive testing including dye penetrant, ultrasonic, and hydrostatic tests

British Rototherm SPGA Safety Pattern and DG/DGX Digital Pressure Gauges

British Rototherm pressure gauges ensure dependable monitoring across liquid and gaseous process networks. The mechanical SPGA range incorporates a solid front Safety Pattern partition, while DG and DGX digital instruments deliver high precision within Zone 0 hazardous installations.

Solid front Safety Pattern construction with baffle wall and blow-out back protective panel
High precision DG75 and DG100 digital gauges delivering measurement accuracy down to 0.05%
Intrinsically safe DGX75 and DGX100 versions rated for ATEX Zone 0 environments with IP67
Broad pressure ranges spanning full vacuum up to hydraulic levels exceeding 1000 bar

British Rototherm Clearscan Mechanical Circular Chart Recorders

Autonomous Clearscan mechanical recorders from British Rototherm deliver uninterrupted pressure and temperature logging on twelve-inch circular chart paper. These instruments are widely deployed for pipeline hydrostatic testing, wellhead verification, and high pressure vessel audits.

Large twelve-inch circular chart format supporting distinct single or dual-pen recording
Self-contained clockwork chart drives available with mechanical spring wound or battery units
Rugged weatherproof housing manufactured from reinforced glass-fiber or light aluminum
Straightforward access to sealed disposable ink cartridges and field chart sheet replacement

British Rototherm Series 300 and Series 700 Industrial Pressure Switches

Pressure and differential pressure switches from British Rototherm provide critical alarm signaling and automatic plant shutdown protection for pumps, compressors, and turbines. Series 300 and 700 units feature robust industrial, explosion-proof ATEX, and pneumatic control packages.

Snap-action microswitch contacts in SPDT and DPDT arrangements with adjustable deadbands
Heavy duty explosion-proof Ex d and Ex ia enclosures suited for petrochemical processing plants
Excellent overpressure resistance with built-in damping defending against severe fluid hammer
Pneumatic output configurations engineered to pilot safety relief valves and line actuators

Operating principle and vibration damping of British Rototherm bimetal helices

British Rototherm BH3 and BH2 industrial bimetallic thermometers convert thermal expansion directly into angular pointer displacement using a precision wound bimetallic coil.

The sensing element comprises two permanently bonded alloy strips exhibiting significantly dissimilar thermal expansion coefficients. When exposed to temperature changes, the helix twists smoothly, driving the center transmission shaft without relying on gear trains or loose mechanical linkages.

The protective instrument housing is filled with high-viscosity damping silicone oil, effectively suppressing high-frequency pipeline vibrations, eliminating pointer flutter, and preventing optical dial fogging during rapid thermal shifts.

Dynamic thermowell stress verification conforming to ASME PTC 19.3 TW standards

When designing industrial thermowells for high-velocity pipelines, British Rototherm engineers perform mandatory dynamic stress calculations in strict adherence to ASME PTC 19.3 TW.

As fluid or gaseous media flows past a cylindrical or tapered thermowell, periodic vortex shedding produces alternating Karman vortex streets.

If the shedding frequency coincides with the natural resonance frequency of the thermowell, catastrophic structural resonance occurs, resulting in fatigue fracture.

The calculation model evaluates frequency ratios, steady-state bending stresses from fluid drag, and maximum process pressure, safeguarding temperature assemblies in critical steam and hydrocarbon lines.

Mineral insulation architecture in heavy-duty Pt100 RTDs and thermocouples

To operate reliably within extreme thermal zones and severe mechanical vibrations, British Rototherm Pt100 sensors and thermocouples are constructed using mineral-insulated metal-sheathed technology.

Inner conductor wires are positioned within a seamless tube of grade AISI 316L stainless steel or heat-resistant Inconel alloy, while internal voids are densely packed with high-purity magnesium oxide powder.

The assembly undergoes rotary swaging into a flexible monolithic sheath that permits bending down to three times its outer diameter without insulation cracking. The dense ceramic matrix isolates conductors from ambient moisture ingress and oxidation, maintaining long-term calibration.

Solid-front Safety Pattern architecture in SPGA industrial pressure gauges

Heavy-duty industrial pressure gauges from the British Rototherm SPGA range are engineered to comply with the stringent Safety Pattern criteria of EN 837-1.

The structural housing incorporates a solid metal baffle wall positioned between the Bourdon sensing tube and the front viewing dial, coupled with a full blow-out back panel secured on flexible clips.

In the rare event of an internal Bourdon tube rupture under extreme pressure surges, process media is directed rearward toward protective plant walls or equipment enclosures.

The laminated safety glass front and solid partition shield field operators from hot process fluids, flying fragments, and hazardous chemical vapors.

Dual-pen kinematics and hydrostatic pipeline testing with Clearscan recorders

Autonomous British Rototherm Clearscan mechanical recorders provide continuous documentary recording of pressure and temperature parameters during pipeline hydrostatic pressure testing.

The unit integrates two separate measuring systems: a heavy-duty Bourdon tube for the pressure channel and a capillary thermal bulb for temperature tracking. Synchronous deflections are transmitted to capillary writing pens via adjustable kinematic linkages protected against overload shock.

Trace recording is executed using specialized quick-drying ink upon a calibrated 300 mm circular chart disk. Rotation is powered by a weekly mechanical spring-wound clockwork movement, ensuring zero electrical dependency in remote fields.

Snap-action microswitches and deadband calibration in Series 300 switches

British Rototherm Series 300 and Series 700 pressure switches incorporate precision snap-action microswitches with dry changeover SPDT and DPDT electrical contacts.

Process pressure acts against a flexible metallic diaphragm or bellows assembly, overcoming the opposing force of a calibrated range spring. Upon reaching the preset actuation limit, the mechanism rapidly toggles electrical contacts, eliminating contact arcing and signal chattering.

A precision deadband adjustment linkage allows independent calibration of setpoint and reset thresholds, preventing unwanted cycling of connected safety shutoff valves and pump sets during transient fluid line surges.

British Rototherm and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of British Rototherm and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.