Core Value

The 2 Wire Straight Tube Probe Type K Thermocouple Sensor is the industry standard for versatile, high-reliability temperature measurement. Engineered with a rigid, seamless metal sheath, this sensor is designed for direct immersion into liquid baths, insertion into high-temperature furnaces, or integration inside protective thermowells. The straight-tube geometry allows for deep penetration into the process media, ensuring the sensing junction bypasses ambient surface temperatures to capture the true core heat of your process.

Calibrated for Type K (Chromel-Alumel), this probe excels in high-temperature environments, offering a standard continuous operating range up to 800°C (1472°F) with standard stainless steel, and up to 1100°C (2012°F) when upgraded to an Inconel 600 sheath. The sensor features heavily insulated lead wires—protected by fiberglass and stainless steel overbraiding—anchored securely to the probe via a high-temperature epoxy or ceramic transition junction. BACKED BY EXTENSIVE SENSOR MANUFACTURING EXPERIENCE and engineered for B2B industrial scaling, every probe UNDERGOES MULTIPLE RIGOROUS QUALITY CHECKS to guarantee strict dimensional tolerances, perfect junction welding, and zero thermal drift.

• ✓ Versatile Straight Geometry: Smooth, rigid tubular design easily slides into standard thermowells, drilled machine blocks, or compression fittings.
• ✓ Wide Temperature Range: Type K calibration provides exceptional linearity and accuracy from room temperature up to extreme furnace heats.
• ✓ Rugged Sheath Materials: Available in 304 SS, 316 SS (for chemical/food processing), and Inconel (for severe high-temp oxidation resistance).
• ✓ Customizable Dimensions: Manufactured in diameters ranging from ultra-thin Ø 1.0mm for fast response, up to heavy-duty Ø 12.0mm for structural rigidity.
• ✓ Mineral Insulated (MI) Options: Premium models feature densely packed Magnesium Oxide (MgO) powder, protecting the internal wires from heavy vibration and allowing the probe to be bent without damaging the circuit.
• ✓ Grounded & Ungrounded Junctions: Choose grounded for the fastest thermal reaction times, or ungrounded to protect PID controllers from electrical noise in conductive liquids.
• ✓ Quality Assured: 100% factory-tested for millivolt signal accuracy, insulation resistance, and mechanical tensile strength at the wire transition.

Technical Specifications & Performance Data

Industrial Applications & Solutions

• Industrial Ovens & Furnaces: Inserted through furnace walls to monitor ambient air temperatures during heat treatment, annealing, and curing processes.
• Liquid Baths & Vats: Direct immersion into oil, water, or mild chemical tanks for electroplating, quenching, and parts washing.
• Plastics & Rubber Processing: Inserted into deep drilled holes in extruder barrels, injection molding platens, and large heated dies.
• Packaging Machinery: Monitoring the core temperature of large sealing bars and hot-melt adhesive tanks.
• Food & Beverage: 316 SS hygienic probes used in commercial baking ovens, brewing tanks, and continuous frying lines.

HT-Heater Straight Probes vs Standard Market Options

Installation & Handling Guidelines

• Immersion Depth: To avoid thermal conduction errors (where the outside air cools the sensor stem), the straight probe should be immersed into the process media by a depth of at least 10 times its diameter.
• Mounting Methods: Straight probes can be fixed in place using adjustable stainless steel compression fittings, allowing you to slide the probe to the exact depth required and lock it securely into the pipeline or tank wall.
• Avoid Bending Standard Tubes: Unless the sensor is specifically ordered as a “Mineral Insulated (MI) bendable probe,” do not attempt to bend the rigid straight tubing, as this will crush the internal ceramic insulators and short the thermocouple wires.
• Transition Zone Heat Limit: Be mindful of the temperature at the transition zone (where the metal tube meets the flexible wire). Standard epoxy transitions should not exceed 260°C. If the ambient air outside the oven is hotter, specify a longer probe tube to move the wire transition further away from the heat source.
• Thermowell Pairing: If measuring highly corrosive fluids or extreme high-pressure steam, insert the straight probe into a matching thermowell. This allows the sensor to be removed for calibration without draining the tank.

Customer Success Stories

Case 1:

Commercial Baking Equipment Manufacturer (Poland)

• Application: Core air temperature monitoring inside continuous rotary baking ovens.

• Challenge: Previous sensors were failing at the wire transition due to radiant heat escaping from the oven walls, melting the wire insulation.

• Solution: Long-reach (300mm) Straight Tube Type K Thermocouples with 304 SS sheaths and high-temperature ceramic potted wire transitions.

• Results: ZERO TRANSITION FAILURES. “By extending the rigid straight tube, HT-Heater moved the vulnerable wire transition safely away from the oven’s radiant heat zone. The probes have been running flawlessly for over 18 months.”

Case 2:

Custom Extrusion Machinery (USA)

• Application: Deep core temperature sensing in large plastic extruder barrel blocks.

• Challenge: Needed highly accurate, long straight probes that wouldn’t shatter internally from the heavy vibration of the extrusion screw.

• Solution: Ø 6.0mm Mineral Insulated (MI) Straight Probes with densely packed MgO insulation and heavy-duty SS braided leads.

• Results: ROCK-SOLID PID STABILITY. “The dense internal insulation makes these probes incredibly durable against machine vibration. Our PID loops are tighter, and extruder temperatures are perfectly stable.”

Pricing & Procurement Options

• Standard Production: Low MOQ available for standard 50mm-150mm lengths. Highly competitive tiered volume discounts for EPC contractors and OEM machine builders.
• Lead Times: Standard Catalog Items (Type K, Ø 5/6mm, up to 150mm length): In stock, 3-5 days. Custom lengths (e.g., 1000mm+), Inconel sheaths, or specialized flanges: 7-10 days.
• Global Logistics: Long straight probes are packed in reinforced, crush-proof shipping tubes to ensure the delicate sheaths arrive perfectly straight and undamaged via express air freight.
• Sample Orders: Available upon drawing or dimension confirmation. Every batch UNDERGOES MULTIPLE RIGOROUS QUALITY CHECKS prior to dispatch.

Global Certifications & Compliance

• CE Marking
  Fully compliant with European safety and environmental standards.
• LVD Compliance
  Low Voltage Directive tested for continuous thermal load safety.
• RoHS Compliant
  Constructed using environmentally safe, lead-controlled brass alloys.
• ISO 9001
  Certified quality control covering CNC machining, coil pressing, and electrical testing.

Quality Documentation: Certificate of Conformity (COC) and insulation resistance test reports included.

Comprehensive After-Sales Support

• • Warranty: 1-Year Comprehensive Warranty covering internal heating element and built-in sensor.

  • Technical Support: Application engineers available for wattage distribution calculation, thermocouple calibration, and nozzle fitting assistance.

  • Global Response Network: BACKED BY 30+ YEARS MANUFACTURING EXPERIENCE with technical inquiry feedback within 2 hours.

Ready to Optimize Your Injection Molding?

Next Steps:

• 📧 Request Custom Quote – Send your nozzle dimensions, wattage, voltage, and HT-CLW-450 drawing requirements.
• 🔧 Free Design Consultation – Work with our thermal engineers to optimize heat distribution and lead insulation.
• 📦 Order Test Samples – Evaluate thermal performance on your injection molding machine.
• 📞 Contact Hot Runner Experts – Response within 2 hours

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