Prototype ring spinning tester with superconducting magnetic bearing

system for high productivity

M Hossain1, M Sparing2, A Berger2, A Abdkader1, D Berger2,G Fuchs2, C Cherif1, L Schultz2

1Institute of Textile Machinery and High Performance

Material Technology (ITM),TU Dresden, Germany, 2IFW Dresden, Institute for Metallic Materials, Dresden, Germany

© techbeyond2020

Technical University of Dresden, Germany

− Development and modification of spinning machines − Manufacturing of hybrid and multi-component yarns for high

performance staple fiber materials (rCF, CF, GF, Basalt) − Sensor and actuator yarns for structural health monitoring of composite

components − Modeling and simulation of the yarn dynamics − Configuration of measuring systems for the analysis of yarn and

machine dynamics

Research Group „Yarn structure and yarn formation technology“

Principle of ringspinning

Twisting of yarn Winding of yarn on cop

Ring/traveler system

Yarn Traveler Ring

Bräcker AG

Ring/traveler system

Principle of ring spinning process

Yarn throughput limited by ring-traveler friction → heat → wear and melting of synthetic yarns

Traveler is dragged along the stationary ring by the yarn and is winding onto the cop.

traveler

ring

yarn

nmax = 25.000 rpm

www.reinersfuerst.de

20 000 rpm

Limitations of ring spinning process

Friction between traveler and ring

Yarn tension

Solutions of Ring/traveler system :

Different material combinations and different shapes of ring/travelers (Fig. a)

Coating of ring/traveler Ring/traveler with air bearing Rotating magnetic ring (Fig. b)

Forces acting on traveler. FR: Frictional force ; Fc: Centrifugal force ; FF: Winding force ; ω: Angular velocity of traveler

x

𝐅𝐅𝐅𝐅 𝐜𝐜𝐜𝐜𝐜𝐜𝛂𝛂 α ω Cop

Ring

Traveler

y

(a) Manual of textile technology, W Klein (b) US7205692 B2 (2007)

𝐅𝐅𝒄𝒄

𝐅𝐅𝐅𝐅

Limitations of ring spinning process

Zero resistance R = 0 Magnetic field is pushed out of the superconductor

Superconductivity, W Buckel

Properties of superconductivity

mag

netic

fiel

d

flux line → magnetic flux quantisation

→ each flux line contains one flux quantum Φo = 2⋅ 10-15 Tm2

mag

netic

fiel

d

pinning center

→ pinning of flux lines on material defects in order to prevent their movement

→ loss-free current j < jc (critical current density)

Properties of superconductivity

Advantages of superconducting bearing system: No necessity of extra control system and sensor Implementation as radial, axial, linear bearing system for high speed

applications such as in linear transport system, turbo machine etc.

Components Example Function Excitation system

Permanent magnet

Provide magnetic flux lines

HTSC Yttrium barium copper oxide (YBCO)

Create levitation force due to flux pinning effect

Cooling system

Liquid nitrogen

(LN2)

Cooling down superconductor

Magnet is levitated above high temperature superconductor in liquid nitrogen (-196°C)

Wikipedia

Superconducting magnetic bearing (SMB)

Superconductor (HTSC) in the magnetic field with acting forces PM: Permanent magnet HTSC: High-temperature superconductor

Arrangement of PM & HTSC using non-magnetic spacer

Cooling HTSC with liquid nitrogen (-196°C)

Anchoring the flux lines of PM in the defects of superconductor

Stable, contact-free bearing of HTSC over PM

Principle of superconducting magnetic bearing

Concept 1: The permanent magnet ring levitates above superconductor coaxially

Concept 2: The permanent magnet levitates inside the superconductor coplanerly

Levitation force: FP~ jC∙A∙dB⁄dz jC : critical current density of super-currents A : effective area between superconducting and magnetic ring dB⁄dz : magnetic field gradient

Concepts of superconducting magnetic bearing

magnetic ring

superconductor

yarn

ring

traveler

Concepts of superconducting magnetic bearing

Delivery rollers

Yarn guide

SMB-System

I

II III

IV

Ring spinning method with superconducting magnetic bearing (SMB)

i. Yarn tension is calculated in four region

ii. Balloon shapes between yarn guide and the yarn guide of permanent magnet

Modeling and Simulation of yarn path

Important parameters for modeling Material : 100% PES (38 mm, 1.14 dtex) Yarn count: 30 tex Spindle speed: 5000-25000 rpm Twist: 700 TPM

Modeling and Simulation of yarn path

Input Parameter

Output Parameter

Spindle speed

[rpm]

F(I)

[cN]

max. balloon- diameter

[mm]

5000 6.23 22.6

10000 16.37 25.3

15000 33.50 28.4

25000 78.90 42.2

Comparison of calculated and measured balloon shapes at the spindle speed of 15000 rpm

Calculated yarn tension at yarn guide

Theoretical balloon shape at 15 000 rpm

Numerical model for yarn forces and balloon shape

Model validation with high-speed camera

15 000 rpm

Integration of SMB-system

N2-Gas discharge

Cryostat Temperature measurement

Magnet LN2 supply

Integration of SMB-system

Vacuum system

500 µm

Hossain M, Abdkader A, Cherif C, Sparing M, Berger D, Fuchs G, and Schultz L. Textile Research Journal 84 8 871-880 (2014) Innovative twisting mechanism based on superconducting technology for higher productivity in ring spinning machine

Yarn spun with ring –traveler Yarn spun with SMB twisting element

SMB yarn: • comparable yarn strength • comparable yarn twist • comparable yarn structure • less yarn irregularities ← reduced friction and temperature during spinning

Yarn Properties with SMB-system

Yarn 30 tex from 100% PES

Yarn Properties with SMB-system

Conception, developement and Implementation of new twisting system based on superconductivity to replace the existing ring/traveler system in ring spinning machine

The advantages of superconducting bearing are the friction-free twisting

element and stable running during spinning, which allow to increase productivity of ring spinning machine.

The yarn properties such as yarn strength, yarn unenvenness, yarn twist and

the microscopic investigation show satisfactory results. The yarn can be spun up to 25000 rpm with this SMB-system. We plan to spin

up to 50000 rpm through the integration of new driving and controlling system in the ring spinning machine.

Conclusion and outlook

Thank you for your kind attention

We would like to thank the German Research Foundation (DFG)

for the financial funding of the research project

Project Partner IFW Dresden, Institute for Metallic Materials, Germany