Heating for hoppers, screw conveyors and rotary valves
Hoppers, Screws and Rotary Valves
Cold surfaces in a dust discharge system can contribute to condensation and deposits. Pro Therm adapts electric heating to hoppers, screw conveyors and rotary valves. Heat demand, available surfaces, operating conditions and maintenance access are assessed as one connected task.
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Assess the complete discharge route
The heating task does not end at the hopper. Transitions to the screw, flanges, nozzles and rotary valve may create local cold spots. We identify the affected components …
The heating task does not end at the hopper. Transitions to the screw, flanges, nozzles and rotary valve may create local cold spots. We identify the affected components and their thermal conditions, aiming for a temperature distribution suited to the discharge process.
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Fit heating surfaces to the geometry
Drawings and dimensions identify available heating surfaces, doors, shafts, nozzles and access openings. Suitable cables or adapted heating elements may be considered …
Drawings and dimensions identify available heating surfaces, doors, shafts, nozzles and access openings. Suitable cables or adapted heating elements may be considered for each component. Heating surfaces, power density and fixings are matched to the temperature requirement and heat transfer.
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Allow maintenance and removal
The discharge system remains equipment requiring mechanical maintenance. Removable parts, inspection openings and wear-part replacement are considered in the heater …
The discharge system remains equipment requiring mechanical maintenance. Removable parts, inspection openings and wear-part replacement are considered in the heater construction. Connections and cable routing should support clear identification. Insulation and heating are coordinated with the required maintenance access.
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Identify cut-outs and mechanical boundaries early
A useful equipment drawing shows doors, shafts, bearings, nozzles, flanges and transitions between discharge components. Heated surfaces and excluded areas are …
A useful equipment drawing shows doors, shafts, bearings, nozzles, flanges and transitions between discharge components. Heated surfaces and excluded areas are identified against that drawing. Heating is not routed across moving parts, dismantling joints or inspection openings without assessment.
Changes to a screw housing or rotary valve require the previous heating arrangement to be reviewed. An overview, current dimensions, required temperatures and insulation construction support the initial assessment. The thermal solution can then be developed together with the mechanical interfaces.
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Frequently asked questions
Which components can be assessed? Hoppers, screw conveyors, rotary valves and thermally critical transitions. The suitable arrangement depends on geometry and process …
Which components can be assessed?
Hoppers, screw conveyors, rotary valves and thermally critical transitions. The suitable arrangement depends on geometry and process data.
Does heating prevent every deposit?
No. Causes and operating conditions need assessment. Heating addresses the thermal duty and does not replace mechanical or process evaluation.
Why are component drawings important?
They show heating surfaces, nozzles, doors, openings and removal areas, which determine arrangement and maintenance access.
Can Pro Therm install the system?
Yes, with its own electric heat tracing teams. Location, scope and interfaces are agreed for the project.
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Related topics
Tank and vessel heating → High-temperature heating → Controls and monitoring → Worldwide installation → Engineering and design → Valves, pumps and instrument lines →
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Understand condensation and deposits
Assessment needs information about the process gas, dust and operating cycle. Dew point, moisture, material properties and shutdown phases may matter. Heating does not …
Assessment needs information about the process gas, dust and operating cycle. Dew point, moisture, material properties and shutdown phases may matter. Heating does not replace analysis of other causes such as mechanical blockage or unsuitable discharge conditions. The thermal task is defined with the operator.
04
Coordinate sensors and operating phases
A sensor at a warm location does not confirm the temperature of every discharge component. Measurement points and circuits are assigned to critical areas. Start-up, …
A sensor at a warm location does not confirm the temperature of every discharge component. Measurement points and circuits are assigned to critical areas. Start-up, normal operation, shutdown and external heating inform controls and required limiting. Hazardous-area duties need assessment of the specific protection concept.
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Independent design and execution
Pro Therm selects suitable heating equipment according to the application, customer preference and budget. Its own teams install electric heat tracing internationally. …
Pro Therm selects suitable heating equipment according to the application, customer preference and budget. Its own teams install electric heat tracing internationally. For your discharge system, we agree engineering, materials, installation and documentation without treating one construction as a universal standard solution.
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Standards and technical basis
Our knowledge section explains how the standards relate to the heating task, product selection and project design. Open the standards overview →
Our knowledge section explains how the standards relate to the heating task, product selection and project design.
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Enquire with a discharge-system drawing
Please send general and component drawings, temperatures, available gas and dust data, insulation, supply and maintenance requirements. Identify cold spots or existing …
Please send general and component drawings, temperatures, available gas and dust data, insulation, supply and maintenance requirements. Identify cold spots or existing deposits.
Enquire about discharge heating →
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References & projects
Explore our project reports for electric heat tracing and frost heave protection. View references & projects →
Explore our project reports for electric heat tracing and frost heave protection.
Understand condensation and deposits
Assessment needs information about the process gas, dust and operating cycle. Dew point, moisture, material properties and shutdown phases may matter. Heating does not replace analysis of other causes such as mechanical blockage or unsuitable discharge conditions. The thermal task is defined with the operator.
Fit heating surfaces to the geometry
Drawings and dimensions identify available heating surfaces, doors, shafts, nozzles and access openings. Suitable cables or adapted heating elements may be considered for each component. Heating surfaces, power density and fixings are matched to the temperature requirement and heat transfer.
Standards reference (checked 14 October 2026): For heating cables and assemblies outside hazardous areas, IEC/IEEE 62395-1:2024 is the international reference for general requirements and testing. Germany still lists DIN EN 62395-1:2014-10 as the current national edition.
Coordinate sensors and operating phases
A sensor at a warm location does not confirm the temperature of every discharge component. Measurement points and circuits are assigned to critical areas. Start-up, normal operation, shutdown and external heating inform controls and required limiting. Hazardous-area duties need assessment of the specific protection concept.
Standards reference (checked 14 October 2026): IEC/IEEE 60079-30-1:2025 and IEC/IEEE 60079-30-2:2025 are international references for resistance trace heating in hazardous areas. Germany still lists DIN EN 60079-30-1:2018-04 and DIN EN 60079-30-2:2018-04 as current national editions. Equipment group, permitted EPL, protection concept and evidence for the actual assembly determine suitability.
Allow maintenance and removal
The discharge system remains equipment requiring mechanical maintenance. Removable parts, inspection openings and wear-part replacement are considered in the heater construction. Connections and cable routing should support clear identification. Insulation and heating are coordinated with the required maintenance access.
Standards reference (checked 14 October 2026): IEC 60079-17:2023, adopted in Germany as DIN EN IEC 60079-17:2024-10, addresses inspection and maintenance of electrical Ex installations. IEC/IEEE 60079-30-2:2025 adds guidance specific to trace heating systems.
Independent design and execution
Pro Therm selects suitable heating equipment according to the application, customer preference and budget. Its own teams install electric heat tracing internationally. For your discharge system, we agree engineering, materials, installation and documentation without treating one construction as a universal standard solution.