(1) Phakathi nenqubo yokukhishwa, izinga lokushisa lolwelwesi lwepayipi lensimbi elivunguzayo liyaqhubeka nokwanda njengoba inqubo yokukhipha iqhubeka. Ekupheleni kwe-extrusion, izinga lokushisa endaweni yodonga lwangaphakathi lwe-lining eduze ne-extrusion die liphakeme kakhulu, lifinyelela ku-631 ° C. Izinga lokushisa lolwelwesi oluphakathi nendawo nesilinda langaphandle alishintshi kakhulu.

(2) Esimweni esingasebenzi, ukucindezeleka okuphezulu okulingana kwepayipi lensimbi evunguzayo yi-243MPa, egxile kakhulu odongeni lwangaphakathi lwepayipi elivunguzayo. Esimeni sokushisa kuqala, inani layo eliphezulu lingu-286MPa, elisatshalaliswa phakathi nendawo yodonga lwangaphakathi lolwelwesi. Ngaphansi kwezimo zokusebenza, ukucindezeleka kwayo okuphezulu okulingana yi-952MPa, okusatshalaliswa kakhulu endaweni enezinga lokushisa eliphezulu ekugcineni kodonga lwangaphakathi. Indawo yokugxilisa ukucindezeleka ngaphakathi kwepayipi lensimbi elivunguzayo isakazwa kakhulu endaweni enezinga lokushisa eliphezulu, futhi ukusatshalaliswa kwayo ngokuyisisekelo kufana nokusatshalaliswa kwezinga lokushisa. Ukucindezeleka okushisayo okubangelwa umehluko wokushisa kunomthelela omkhulu ekusabalaleni kokucindezeleka kwangaphakathi kwepayipi lensimbi elivunguzayo.

(3) Ukucindezeleka kwe-radial epayipini lensimbi elivunguzayo. Esimweni esingasebenzi, ipayipi yensimbi ye-spiral ithinteka kakhulu yi-prestress ehlinzekwa yi-prestress yangaphandle. Ipayipi lensimbi elivunguzayo lisesimeni sokucindezeleka esicindezelayo ohlangothini lwe-radial. Inani elikhulu kunawo wonke yi-113MPa, esabalaliswa odongeni olungaphandle lwepayipi lensimbi elivunguzayo. Esimeni sokushisa, ukucindezela kwayo okuphezulu kwe-radial ngu-124MPa, kugxilwe kakhulu ebusweni bokugcina obungaphezulu nobuphansi. Esimeni sokusebenza, ukucindezela kwayo okukhulu kwe-radial kungu-337MPa, okugxilwe kakhulu endaweni ephezulu yepayipi yensimbi evunguzayo.