Sage Journals: Discover world-class research

Abstract

A cylindrical microwave cavity operating in the TM₀₁₀ mode at 2450MHz has been incorporated in a Microwave Assisted Pultrusion (MAP) line to monitor continuously the quality of a cylindrical 6.0mm diameter solid rod for use as a tension member in optical cables. The cavity is coupled to a HP 8753C vector network analyser and measures in realtime the quality factor and shift in resonant frequency of the cavity as the profile passes through it en route to the haul-off. The measurements are used to calculate the dielectric constant and loss tangent of the profile. The results can be associated with degree of cure of the profile and may be used to prescribe a process window where quality is related directly to line speed, power input, etc. The technique could be used as the basis of a feedback control system in pultrusion.

Get full access to this article

View all access options for this article.

References

Steiner

R.L.

, Cole

J.D.

, Strong

A.B.

and Todd

R.H.

, SAMPE Quarterly, Oct. (1992) 38.

Zukas

W.X.

, Polym. Eng. Sci., 29, 22, (1989) 1553.

For example, MacKinnon

A.J.

, Pethrick

R A.

, Jenkins

S.D.

, and McGrail

P.T.

, MRS, Macromolecules, 25, 13 (1992) 3492.

Methven

J.M.

, and Ghaffariyan

S.R.

, Design of a TM₀₁₀ Single Mode Resonant Cavity as a Preheating and Crosslinking Die in Pultrusion, in Microwave Processing of Materials II, 189, Materials Research Society, (1991).

Katramados

, On-Line Quality Monitoring of a Pultrusion Process using Dielectric Measurements, MSc Thesis, Department of Mechanical Engineering, UMIST, (1994).

Hewlett Packard 8753C Network Analyzer Documentation Map and User's Operating Manual (1989).

, Stumper

, IEE Proc., 132H (1) (1985) 27.

Jow

, Hawley

M.C.

, Finzel

M.C.

, Rev. Sci. Instrum., 60(1), (1989) 96.

Kraszewski

A.W.

, Nelson

S.O.

, Microwave Resonator as a Dielectric Object Sorting Device: Advantages and Limitations, 21st Microwave Conference, Stuttgart, Germany, (1991), Microwave Exhib. & Publ. Ltd, London, 435.

10.

Estin

A.J.

, Bussey

H.E.

, Errors in Dielectric Measurements Due to a Sample Insertion Hole in a Cavity, IEEE Transactions on Microwave Theory and Techniques MTT-8(11) (1960) 650.

11.

, Bosissio

R.G.

, IEEE Transactions on Microwave Theory and Techniques MTT-30(1), (1982) 100.

12.

Waldron

R.A.

, Theory of Guided Electromagnetic Waves, Van Nostrand Reinhold Company, (1970).

13.

Ghaffariyan

S.R.

, Microwave Assisted Pultrusion, PhD Thesis, Department of Mechanical Engineering, UMIST, (1992).

14.

EEC Recommendation, Recommended Methods for the Determination of the Dielectric Properties of Insulating Materials at Frequencies Above 300MHz, Publication 377-1, (1973).

15.

Meyer

, IEEE Trans. on Microwave Theory and Techniques, MTT-25(12), 7 (1977), 1092.

16.

Metaxas

A.C.

, Meredith

R.J.

, Industrial Microwave Heating, IEE Power Engineering Series 4, Peter Perigrinus Ltd, London, (1983).

17.

Blythe

A.R.

, Electrical Properties of Polymers, Cambridge University Press, Cambridge (1979).

18.

E.R.A. Report Ref. L/S9, Methods of Testing Permittivity and Loss Tangent, (1963). See also Baird

M. E.

, Electrical Properties of Polymeric Materials, The Plastics Institute, London, (1973).

19.

Methven

J.M.

, and Bush

S.F.B.

, a Mechanism for Observed Rate Enhancement in a Microwave Applicator based on the Concept of a Non-Equilibrated Temperature Reaction, 39th SAMPE Symposium, Anaheim, April 11–14 (1994).

20.

C.C.

and Liepens

, Electrical Properties of Polymers, Hanser (1987).

In-Line Quality Monitoring of Pultruded Profiles using Dielectric Measurements

Abstract

Get full access to this article

References