Namel long ol yusa husat i save yusim ol bikpela-diamita stop valv long olgeta de, ol manmeri i save ripotim wanpela hevi, em olsem, bikpela-}diamita stop valv i save hat long pasim taim ol i yusim ol long midia wantaim ol bikpela presa i narapela narapela, olsem stim, hai{2}}presa wara, na ol narapela samting, taim ol i wok aninit long presa. Sapos ol i pasim strong, oltaim ol i painim olsem bai i gat lik, na i hatwok long pasim strong. Risen bilong dispela hevi em i no gat straksel disain bilong valv na mak bilong mak bilong mak bilong mak bilong man.
Skelim ol As Bilong Ol He
Laspela horisontel autput pawa bilong wanpela jeneral adalt em 60-90kg, i dipen long ol narapela narapela bodi.
Jenerali, flow daireksen bilong shut-of valv i kamap bilong stap daunbilo long na hai aut. Taem wan man i klosem valv, bodi blong man i pusum hanwil i go stret blong muvum valv disk i go daon blong kasem klosing. Long dispela taim, ol i mas winim tripela strong, em olsem:
(1) Axial thrust Fa;
(2) Friksen namel long peking na valv stem Fb;
(3) Friksen fos Fc bilong kontek namel long valv stem na valv kor
Total tok em ∑M=(Fa+Fb+Fc)R
Yumi ken lukim olsem taim autlet daiamita i bikpela moa, bikpela strong bilong sutim tok i go bikpela moa. Taem hem i kolosap long klos stet, aksial thrust fos i kolosap kolosap long stret presa blong paep netwok (from P1-P2≈P1, P{4}} taem i klos)
Olsem, sapos ol i yusim wanpela DN200 stop valv long wanpela 10bar stim paip, namba wan samting tasol i pasim aksial thrust Fa=10×πr2=3140kg, na horisontal seimferensiel fos ol i nidim bilong pasim i klostu long horisontel autput bilong wanpela nomol bodi bilong man. Mak bilong strong, olsem na i hatwok tru long wanpela man i pasim tru valv aninit long ol dispela kain wok.
I tru, sam faktri oli talem se oli mas putum kaen valv ya long rod we i no stret, we i stretem problem blong hadtaem blong klosem, be i gat problem tu blong harem nogud blong openem afta we oli klosem.
Analisis bilong ol As bilong Intenel Likej bilong Bikpela Daiamita Globe Valf.
Ol bikpela valv bilong stop ol i save yusim long ol boila autlet, ol bikpela sab-silinda, ol stim main, na ol narapela samting. Ol dispela posisen i gat ol dispela hevi:
(1) Jenerali, presa difrens long aotlet blong boiler i bigwan lelebet, mekem se stim flow rate tu i bigwan moa, mo damej blong erosen long siling pes tu i bigwan moa. Antap long dispela, boiler kombusen efisiens i no inap 100%, we bai mekim stim long autlet bilong boiler i gat bikpela wara konten, we i luk olsem bai kamapim kavitasen na kavitesen bagarap long valv siling pes.
(2) Long shut-of valv klostu long autlet bilong boiler na sab-silinda, bikos stim i kam aut tasol long boiler i gat ol samting i kamap namel long taim bilong hatim tumas, long taim bilong saturesen, sapos boiler wara softening tritmen i no gutpela tumas, hap bilong en bai planti taim i kamap hariap. Ol samting i gat as na alkali bai kamapim korosen na erosen long siling pes; sampela samting i gat kristalais inap tu long pas long valv siling pes na kristalais, na dispela i mekim na valv i no inap pas gut.
(3) Ol valv bilong putim insait na autlet bilong Sub{1}}}}}}}cilinda i go insait. Amaon blong stim we oli yusum afta we valv i bigwan o smol from ol samting we oli nidim blong mekem mo ol nara risen. Taem we flow rate i jenis bigwan, i isi blong mekem se i laet, kavitesen, mo ol narawan. Kos i erosen, kavitesen mo ol narafala samting we i spolem valv siling pes.
(4) Jenerali, taem wan bigfala-}diamita paeplaen i open, paeplaen i nid blong gat preheatem, mo proses blong preheting i jenerol i nidim wan smol flo blong stim blong pas tru long hem, blong mekem se paeplaen i save kam hot slo mo i sem mak i go kasem wan spesel level bifo shut shut tempereja inkris, damej pat blong valv blong koneksen we i mekem se i gat paep i kam antap. Tasol, long dispela proses, valv i op i liklik tru, na dispela i mekim na mak bilong erosen i bikpela tru winim nomol yus efek, na i daunim tru sevis laip bilong valv siling pes.
Ol rot bilong stretim hevi Opening na Klosing bilong ol Bikpela Daiamita Globe Valvs
(1) Namba wan, em i gutpela long makim wanpela belo-}sil globe valv long abrusim friksen resistens bilong plunger valv na valv bilong pakim na mekim swit i isi.
(2) Ol i mas wokim valv kor na sia long ol samting i gat gutpela erosen resistens na ol samting bilong pasim, olsem Stelit simen kabait;
(3) I gud blong adoptem wan dabol valv disk strakja, we bae i no kosem tumas erosen from smol opening, we bae i afektem sevis laef mo siling ifek.
