Determination of tension strength in the longitudinal and circumferentional direction in glass-polyester composite pipes

Abstract

Polymer composite pipes with glass fiber reinforcement have today a wide usage in the chemical and process industries. The basic subject of this paper is the determination and distribution of stresses and strains in longitudinal and circumferentional directions of glass-polyester pipes under tension test. Also, the tension strengths in both directions are determined out. Tension test was performed on an electro-mechanical test machine on flat samples and rings obtained by cutting of pipes produced by the method 'Filament winding' with glass fibers reinforcement ±55°. Also, the micromechanical analysis on fracture surfaces was done by SEM, which provided the knowledge about models and mechanisms of fracture on applyed loading.

Cevi od polimernih kompozita sa staklenim ojačanjem danas imaju široku primenu u hemijskoj i procesnoj industriji. Predmet ovog rada je određivanje i raspodela napona i deformacija u uzdužnom i obimnom (tangencijalnom) pravcu staklo-poliester cevi pri ispitivanju zatezanjem. Takođe, određena je i zatezna čvrstoća u oba navedena pravca. Ispitivanje zatezanjem je izvedeno na elektromehaničkim kidalicama na ravnim uzorcima i prstenovima sečenim od cevi proizvedenih metodom namotavanja, sa namotavanjem staklenog ojačanja pod uglom ±55°. Mikromehanička analiza je izvedena na površinama preloma korišćenjem SEM, na osnovu koje su pretpostavljeni modeli i mehanizmi nastanka loma usled primenjenih opterećenja.