Njengoba izidingo zabantu zokuvikela imvelo ziya ngokuya ziba nzima, izidingo zamavalvu nazo ziyanda, futhi izidingo zezinga lokuvuza elivumelekile lezinto ezinobuthi, ezivuthayo neziqhumayo ezitshalweni ze-petrochemical ziya ngokuya ziba nzima. Amavalvu ayimishini ebalulekile ezitshalweni ze-petrochemical. , Ukuhlukahluka kwawo kanye nobuningi bawo kukhulu, futhi kungenye yemithombo eyinhloko yokuvuza kudivayisi. Kwizinto ezinobuthi, ezivuthayo neziqhumayo, imiphumela yokuvuza kwangaphandle kwevalvu inzima kakhulu kunokuvuza kwangaphakathi, ngakho-ke izidingo zokuvuza kwangaphandle kwevalvu zibaluleke kakhulu. Ukuvuza okuphansi kwevalvu kusho ukuthi ukuvuza kwangempela kuncane kakhulu, okungenakunqunywa ngokuhlolwa okuvamile kokucindezela kwamanzi kanye nokucindezela komoya. Kudinga izindlela zesayensi ezengeziwe kanye nezinsimbi eziyinkimbinkimbi ukuthola ukuvuza okuncane kwangaphandle.

Izindinganiso ezivame ukusetshenziswa zokuthola ukuvuza okuphansi yi-ISO 15848, API624, indlela ye-EPA 21, i-TA luft kanye ne-Shell Oil Company SHELL MESC SPE 77/312.

Phakathi kwazo, isigaba se-ISO A sinezidingo eziphakeme kakhulu, kulandelwe isigaba se-SHELL A. Kulokhu,I-NSEN ithole izitifiketi ezilandelayo ezijwayelekile;

Isigaba A se-ISO 15848-1

I-API 641

I-TA-Luft 2002

Ukuze kuhlangatshezwane nezidingo zokuvuza okuphansi, ukuthungwa kwama-valve kudingeka kuhlangatshezwane nezidingo zokuhlolwa kwegesi ye-helium. Ngenxa yokuthi isisindo sama-molecule sama-molecule e-helium sincane futhi kulula ukungena, ikhwalithi yokuthungwa iyisihluthulelo. Okwesibili, ukuthungwa phakathi komzimba we-valve kanye nesembozo sokugcina kuvame ukuba uphawu lwe-gasket, oluyi-static seal, okulula ukuhlangabezana nezidingo zokuvuza. Ngaphezu kwalokho, ukuthungwa esiqwini se-valve kuyi-dynamic seal. Izinhlayiya ze-graphite zikhishwa kalula ekupakisheni ngesikhathi sokunyakaza kwesiqu se-valve. Ngakho-ke, ukupakisha okukhethekile okuphansi kokuvuza kufanele kukhethwe futhi ukuthungwa phakathi kokupakisha kanye nesiqu se-valve kufanele kulawulwe. Ukuthungwa phakathi kwesigqoko sokucindezela kanye nesiqu se-valve kanye nebhokisi lokugcwalisa, kanye nokulawula ukujiya kokucubungula kwesiqu se-valve kanye nebhokisi lokugcwalisa.