Planetary Roller Extruder Cooling Module Design

Solution Overview

Problem

Planetary roller extruders face challenges in achieving effective cooling before discharge, which affects the stability and shape of the melt, and existing cooling systems do not adequately address the need for efficient heat dissipation and temperature control.

Innovation Solution

The implementation of a cooling module with a housing adapted to the dimensions of other extruder modules, featuring a high filling level, choke at the outlet, melt entry under pressure, and minimized mechanical energy input, along with reduced planetary spindle distance and speed, to enhance cooling efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a planetary roller extruder section is used for processing melts, then mixing and conveying effects are improved, but cooling capacity is insufficient

Engineering Contradiction:

Improvemixing and conveying efficiencyVSAvoidcooling capacity

Core Design Contradiction:

ProductivityVSTemperature

Solution Approach 1:

The extruder is divided into functionally distinct sections: a first planetary roller extruder section for mixing and conveying, and a second planetary roller extruder section specifically designed for cooling. This segmentation allows each section to optimize its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second extruder section is specifically designed with enhanced cooling characteristics, including different geometric parameters (L/D ratio, channel depth) compared to the first section. This local optimization of cooling capacity in the second section addresses the insufficient cooling while preserving the mixing efficiency in the first section.

Inventive Principle:

Principle #3Local quality

2Temperature

If cooling channels are added to increase cooling effect, then temperature control is improved, but device complexity increases

Engineering Contradiction:

Improvecooling effectVSAvoidcooling system complexity

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The second planetary roller extruder section serves dual functions: it continues the mixing and conveying operations while simultaneously providing enhanced cooling through its specifically designed geometry and cooling channels. This multi-functionality avoids the need for separate cooling devices, thereby limiting complexity increase.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The cooling capacity is enhanced by modifying geometric parameters of the second section, such as increasing the L/D ratio and cooling channel depth, rather than adding complex active cooling systems. This approach improves cooling effect through passive design modifications.

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If melt is cooled more effectively before discharge, then product stability is improved, but energy input requirements increase

Engineering Contradiction:

Improvemelt stabilityVSAvoidenergy input

Core Design Contradiction:

Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

The friction and mechanical energy input, which normally generate unwanted heat, are utilized beneficially in the second extruder section to maintain melt temperature and stability during the cooling process. The cooling channels are designed to remove only excess heat while retaining enough thermal energy for product stability.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The planetary spindles continue to rotate and mix the melt continuously through the second extruder section, providing ongoing mechanical energy input that maintains melt homogeneity and stability throughout the cooling process, preventing energy deficits.

Inventive Principle:

Principle #20Continuity of useful action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution significantly reduces melt temperature, improves cooling capacity, and maintains the stability of the melt during discharge, ensuring consistent product quality and efficient processing.

Implementation Method 1

The implementation of a cooling module with a housing adapted to the dimensions of other extruder modules, featuring a high filling level, choke at the outlet, melt entry under pressure, and minimized mechanical energy input, along with reduced planetary spindle distance and speed, to enhance cooling efficiency

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

The implementation of a cooling module with a housing adapted to the dimensions of other extruder modules, featuring a high filling level, choke at the outlet, melt entry under pressure, and minimized mechanical energy input, along with reduced planetary spindle distance and speed, to enhance cooling efficiency

Methodology Applied

Scientific EffectConvection: Convection

Data Source

PatentUS11446617B2Extruder with planetary roller section for cooling melts

Publication Date: 2022.09.20 ENTEX RUST & MITSCHKE GMBH

AI summary

Various measures increase the cooling effect on a planetary roller extruder section/module. Those measures include a choke being arranged at an outlet of the planetary roller extruder section or module, a distance between centerlines of adjacent planetary spindles being at least equal to an outer diameter of the planetary spindles, providing a pressurized melt supply, having a cooling section composed of several sections/modules, providing at least one section/module in which a flow, during melt supply is converse to the conveying direction of the extruder, and providing cooling tubes arranged within the central spindle.