I-valve yokusiza, eyaziwa nangokuthi i-valve yokukhulula ingcindezi (i-PRV), uhlobo lwe-valve yokuphepha esetshenziselwa ukulawula noma ukunciphisa ingcindezi ohlelweni. Uma ingcindezi ingalawulwa, ingakheka futhi iholele ekuphazamisekeni kwenqubo, ukwehluleka kwethuluzi noma imishini, noma umlilo. Ngokuvumela uketshezi olucindezelwe ukuthi luphume ohlelweni ngendlela ewusizo, ingcindezi iyancishiswa. Ukuze kuvinjelwe imikhumbi yengcindezi neminye imishini ukuthi ibhekane nengcindezi edlula imikhawulo yayo yokuklama,ivalvu yokusizayakhelwe noma ihlelwe ukuthi ivuleke ngengcindezi ethile ebekwe.

Iivalvu yokusizaiba "indlela yokumelana okuncane" lapho ingcindezi ebekiwe idlula ngoba ivalvu iphoqelekile ukuthi ivuleke futhi olunye uketshezi luqondiswa kabusha kusiteshi esisizayo. Ingxube yoketshezi, igesi, noma igesi ewuketshezi ephambukiselwa ezinhlelweni ezinoketshezi oluvuthayo iyabuyiselwa noma ikhishwe umoya.

[1] noma ngabe ithunyelwa ngesistimu yamapayipi eyaziwa ngokuthi i-flare header noma i-relief header iye ku-gas flare ephakathi nendawo ephakeme lapho ishiswa khona, ikhipha amagesi okushisa angenalutho emkhathini, noma ngesistimu yokubuyisa umusi ophansi, ogeleza kakhulu.

[2] Ezinhlelweni ezingezona eziyingozi, uketshezi luvame ukukhishwa emoyeni ngepayipi elifanele lokukhipha elibekwe ngokuphephile kubantu futhi elakhelwe ukuvimbela ukungena kwemvula, okungathinta ingcindezi yokuphakamisa esethiwe. Ingcindezi izoyeka ukwakheka ngaphakathi komkhumbi njengoba uketshezi luqondiswa kabusha. Ivalvu izovala lapho ingcindezi ifinyelela ingcindezi yokuhlala kabusha. Inani lengcindezi okumele lincishiswe ngaphambi kokuba ivalvu ihlale kabusha laziwa ngokuthi i-blowdown, evame ukuvezwa njengephesenti lengcindezi esethiwe. Amanye amavalvu ane-blowdown elungisekayo, futhi i-blowdown ingahluka phakathi kuka-2% no-20%.

Kunconywa ukuthi indawo yokukhipha ivalvu yokukhulula ezinhlelweni zegesi ezinomfutho ophezulu ibe semoyeni ovulekile. Ukuvulwa kwevalvu yokukhulula kuzobangela ukwakheka kwengcindezi ohlelweni lwamapayipi olungezansi kwevalvu yokukhulula ezinhlelweni lapho indawo yokukhipha ixhunywe khona kumapayipi. Lokhu kuvame ukusho ukuthi lapho ingcindezi oyifunayo ifinyelelwa, ivalvu yokukhulula ngeke iphinde ihlale. Amavalvu okukhulula okuthiwa “ahlukile” avame ukusetshenziswa kulezi zinhlelo. Lokhu kubonisa ukuthi ingcindezi izikhandla kuphela endaweni encane kakhulu kunokuvulwa kwevalvu.

Umfutho wokuphuma kwevalvu ungagcina kalula ivalvu ivuliwe uma ivalvu ivuliwe ngoba umfutho kumele wehle kakhulu ngaphambi kokuba ivalvu ivale. Njengoba umfutho ohlelweni lwepayipi lokukhipha umoya ukhuphuka, amanye amavalvu okusiza axhunywe ohlelweni lwepayipi lokukhipha umoya angase avuleke. Lokhu kuyinto okufanele uyikhumbule. Lokhu kungabangela ukuziphatha okungathandeki.