Flexible Manifold Tubular Heaters for Hot Runner Systems (Formable)
Hongtai flexible manifold tubular heaters are designed for the precise heating of hot runner plates and complex mold manifolds. Manufactured using a specialized high-temperature annealing process, these elements are hand formable, allowing users or mold makers to bend the heater into the machined grooves of the manifold plate without specialized tools.
Available in both round and square cross-sections, the square heating element profile offers increased surface contact area for superior heat transfer efficiency compared to standard round tubes.
Key Features:
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Flexibility: Soft-annealed sheath allows for easy 2D or 3D installation into mold grooves.
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Profile Options: Round (Standard) or Square/Rectangular (High Contact).
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Max Temperature: Up to 700°C (Sheath temp).
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Sheath Material: Stainless Steel 304 / 321.
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Tolerance: Precision diameter control (±0.05mm) for tight press-fit.
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Installation: Press-fit installation requiring no cement.
SECTION 1: Technical Specifications & Dimensions
| Parameter | Standard Round | Standard Square | Customizable |
| Diameter / Section | 6.5mm, 8.0mm, 8.5mm, 10mm | 6x6mm, 8x8mm | Custom sizes |
| Diameter Tolerance | ±0.05mm | ±0.05mm | Precision Fit |
| Voltage | 230V / 400V | 230V / 400V | – |
| Min Bending Radius | 12mm – 15mm | 12mm – 15mm | Center Start |
| Cold Zone | 30mm (Standard) | 30mm (Standard) | Custom Length |
| Connection | Threaded Stud / Lead Wire | Threaded Stud | – |
Figure : Cross-Section Comparison.
Left: Standard Round Tube. Right: Square Profile (Hot runner heater). The square profile maximizes contact with the mold groove bottom and sides, improving thermal conductivity by up to 30%.
SECTION 2: Industrial Applications
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Plastic Injection Molding: Heating of hot runner manifolds and distribution plates.
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Die Casting: Nozzle and sprue bushing heating.
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Packaging Machinery: Sealing bars requiring complex heating profiles.
SECTION 3:Installation Guide (Forming & Fit)
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Groove Preparation: Ensure the manifold groove is machined to the correct tolerance (usually +0.1mm relative to heater diameter) to ensure a tight fit.
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Hand Forming: These hand formable heaters are supplied in a fully annealed (soft) state. Start bending from the center of the heater (marked) and work outwards towards the terminals.
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Press Fit: Use a soft mallet to gently press the heater into the groove. Once heated, the element will expand slightly to lock into the groove, ensuring maximum heat transfer.
SECTION 4: Why Choose Square Section?
While round heaters have line contact with the manifold groove, square heating elements provide three-sided surface contact. This significantly reduces the temperature difference between the element and the mold steel, allowing for faster start-up times and more uniform temperature distribution across the manifold.
SECTION 5: FAQ
Q: Do I need special tools to bend these heaters?
A: No. Because they are fully annealed, they can be formed by hand or with simple bending jigs to fit your specific manifold layout. Avoid sharp bends smaller than the minimum radius (12-15mm).
Q: Do you stock standard lengths?
A: We stock a wide range of straight lengths (e.g., 500mm to 2000mm) that are ready to be formed. Custom power and length configurations are manufactured to order.
Q: What is the lead time for custom flexible heaters?
A: For standard diameters (6.5mm, 8mm, 8x8mm), we can often ship within 3-5 working days. Custom diameters may require 7-10 days.
