Dehydrogenation kurapwa, inozivikanwawo sedehydrogenation heat treatment, kana post-weld heat treatment.
Chinangwa chekurapa-kupisa kwenzvimbo yeweld pakarepo mushure mekushongedza ndiko kuderedza kuoma kwenzvimbo yeweld, kana kubvisa zvinhu zvinokuvadza senge hydrogen munzvimbo ye weld. Panyaya iyi, iyo post-heat treatment uye post-weld heat treatment ine imwechete chikamu chekuita.
Mushure mekupisa, kupisa kunoderedza kutonhora kweiyo weld seam uye welded joint kukurudzira kubuda kwehydrogen uye kudzivirira kuwedzera kwekuoma.
(1) Mushure-kupisa nechinangwa chekuvandudza kushanda kwejoini yakashongedzwa uye kuderedza kuoma kwayo kunogona kushanda chete kana iyo welding zone ichiri pane tembiricha yakakwira mushure mekupisa.
(2) Afterheating kudzivirira kutsika-kupisa kutsemuka kunonyanya kukurudzira kubviswa kwakakwana kwesimba rehydrogen munzvimbo yewelding.
Kubviswa kwehydrogen kunoenderana nekushisa uye kubata nguva yemashure ekupisa. Iyo tembiricha yechinangwa chikuru chekubvisa hydrogen kazhinji 200-300 madhigirii, uye nguva yekupisa-kupisa ndeye 0.5-1 awa.
Kune welds mune anotevera mamiriro, post-thermal hydrogen kubvisa kurapwa kunofanirwa kuitwa nekukurumidza mushure mewelding (4 mapoinzi):
(1) Hukobvu hukuru kupfuura 32mm, uye zvinhu zvakajairwa kusimba simba σb> 540MPa;
(2) Low-alloy simbi zvinhu zvine ukobvu kupfuura 38mm;
(3) Iyo butt weld pakati peiyo yakadzikwa muromo uye yekumanikidza mudziyo;
(4) Welding maitiro ekuongorora anoona kuti hydrogen kubvisa kurapwa kunodiwa.
Kukosha kwekupisa kwemashure-kupisa kunowanzo kuratidzwa neinotevera fomula:
Tp＝455.5[Ceq]p－111.4
Mune fomula, Tp——post-heating tembiricha ℃;
[Ceq]p——Carbon yakaenzana formula.
[Ceq]p=C+0.2033Mn+0.0473Cr+0.1228Mo+0.0292Ni+0.0359Cu+0.0792Si－1.595P+1.692S+0.844V
Kuderedza hydrogen zvirimo munzvimbo weld imwe yeakakosha mhedzisiro yepost kupisa kurapwa. Sekureva kwemishumo, pa298K, maitiro ehydrogen diffusion kubva pasi kabhoni simbi welds ndeye 1.5 kusvika 2 mwedzi.
Kana tembiricha yawedzerwa kusvika pa320K, kuita uku kunogona kupfupikiswa kusvika pamazuva maviri kusvika matatu nehusiku, uye mushure mekupisa kusvika ku470K, zvinotora maawa gumi kusvika gumi nemashanu.
Basa guru rekupisa-kupisa uye dehydrogenation kurapwa nderokudzivirira kuumbwa kwekuputika kwechando musimbi ye weld kana munzvimbo inopisa.
Kana iyo preheating ye weldment isati yave yakakwenenzverwa kudzivirira kuumbwa kweanotonhora makatsemuka, senge muwelding yemajoini akanyanya-kumanikidza uye yakaoma-ku-weld simbi, iyo post-heating process inofanirwa kushandiswa kudzivirira yakavimbika kuumbwa. yezvimedu zvinotonhora.
Nguva yekutumira: Mar-29-2023
