Njengoko iimfuno zabantu zokukhusela okusingqongileyo ziya zisiba nzima ngakumbi, iimfuno zeevalvu nazo ziyanda, kwaye iimfuno zenqanaba lokuvuza elivumelekileyo lezinto ezinobuthi, ezitshayo neziqhumayo kwizityalo zepetrochemical ziya zisiba nzima ngakumbi. Iivalvu zizixhobo eziyimfuneko kwizityalo zepetrochemical. , Uhlobo lwazo kunye nobungakanani bazo bukhulu, kwaye yenye yezona ndawo ziphambili zokuvuza kwisixhobo. Kwizinto ezinobuthi, ezitshayo neziqhumayo, iziphumo zokuvuza kwangaphandle kwevalvu zinzima kakhulu kunokuvuza kwangaphakathi, ngoko ke iimfuno zokuvuza kwangaphandle kwevalvu zibaluleke kakhulu. Ukuvuza okuphantsi kwevalvu kuthetha ukuba ukuvuza kwangempela kuncinci kakhulu, okungenakuqinisekiswa ngovavanyo oluqhelekileyo loxinzelelo lwamanzi kunye noxinzelelo lomoya. Ifuna iindlela zesayensi ezingaphezulu kunye nezixhobo ezintsonkothileyo zokufumanisa ukuvuza okuncinci kwangaphandle.

Imigangatho esetyenziswa rhoqo ekufumaneni ukuvuza okuphantsi yi-ISO 15848, API624, EPA method 21, TA luft kunye neShell Oil Company SHELL MESC SPE 77/312.

Phakathi kwazo, iklasi ye-ISO A ineemfuno eziphezulu, ilandelwa yiklasi ye-SHELL A. Ngeli xesha,I-NSEN ifumene ezi zatifikethi zilandelayo ezisemgangathweni;

Iklasi ye-ISO 15848-1 A

I-API 641

TA-Luft 2002

Ukuze kuhlangatyezwane neemfuno zokuvuza okuphantsi, ii-valve castings kufuneka zihlangatyezwene neemfuno zovavanyo lwegesi ye-helium. Ngenxa yokuba ubunzima beemolekyuli ze-helium molecules buncinci kwaye kulula ukungena, umgangatho we-casting yeyona nto iphambili. Okwesibini, itywina phakathi komzimba wevalvu kunye nesigqubuthelo sokugqibela sidla ngokuba yi-gasket seal, eyi-static seal, elula ukuhlangabezana neemfuno zokuvuza. Ngaphezu koko, itywina kwi-valve stem yi-dynamic seal. Amasuntswana e-graphite akhutshwa lula kwiphakheji ngexesha lokuhamba kwe-valve stem. Ke ngoko, kufuneka kukhethwe ukupakisha okukhethekileyo okuphantsi kokuvuza kwaye isithuba phakathi kwephakheji kunye nesiqu sevalvu kufuneka silawulwe. Isithuba phakathi kwe-sleeve yoxinzelelo kunye nesiqu sevalvu kunye nebhokisi yokuzalisa, kwaye kulawulwe uburhabaxa bokucubungula kwe-valve stem kunye nebhokisi yokuzalisa.