Welding igwe anaghị agba nchara na-achọ nhọrọ nke shielding gas iji nọgide na-enwe metallurgical mejupụtara na metụtara anụ ahụ na n'ibu Njirimara.Common ikpuchi gas ọcha maka igwe anaghị agba nchara na-agụnye argon, helium, oxygen, carbon dioxide, nitrogen, na hydrogen (lee Figure 1) A na-ejikọta gas ndị a n'ogo dị iche iche iji kwado mkpa nke ụdị nnyefe dị iche iche, ụdị waya, ala alloys, profaịlụ bead chọrọ na ọsọ ọsọ.
N'ihi na ogbenye thermal conductivity nke igwe anaghị agba nchara na dịtụ "oyi" ọdịdị nke mkpụmkpụ-circuit nyefe gas metal arc ịgbado ọkụ (GMAW), usoro na-achọ a "tri-mix" gas esịnede 85% ka 90% helium (He), ruo 10 % Argon (Ar) na 2% ka 5% Carbon Dioxide, 7% ngwakọta nke 90% na ngwakọta. 2-1 / 2% CO2. Nnukwu ike nke ionization nke helium na-akwalite arcing mgbe obere oge gasịrị;tinyere ya elu thermal conductivity, ojiji nke Ọ na-abawanye na fluidity nke a wụrụ awụ ọdọ mmiri. The Ar akụrụngwa nke Trimix na-enye izugbe shielding nke weld puddle, mgbe CO2 eme dị ka a reactive akụrụngwa kwụsie ike na arc (lee Figure 2 maka otú dị iche iche ichebe gas na-emetụta weld bead profaịlụ).
Ụfọdụ ngwakọta ternary nwere ike iji oxygen dị ka ihe nkwụsịtụ, ebe ndị ọzọ na-eji ngwakọta He / CO2 / N2 iji nweta otu mmetụta ahụ.
The nnukwu ndudue emepụta eme na-agbalị ka short-circuit GMAW igwe anaghị agba nchara na otu gas ngwakọta (75 Ar / 25 CO2) dị ka nwayọọ ígwè, na-emekarị n'ihi na ha achọghị ijikwa ihe mmezi cylinder.This ngwakọta nwere nke ukwuu carbon.N'ezie, ọ bụla na-echebe gas eji maka siri ike waya kwesịrị inwe a kacha nke 5% carbon dioxide.Using ibu ichekwa na a metallurgy carbon-grade nke na-abụghị alloy 0 echiche dị n'okpuru ọkwa L. cessive carbon na shielding gas nwere ike ịmepụta chromium carbides, nke na-ebelata corrosion iguzogide na n'ibu Njirimara.Soot nwekwara ike ịpụta na weld elu.
Dị ka a n'akụkụ ndetu, mgbe ahọpụta metals maka shorting GMAW maka 300 usoro base alloys (308, 309, 316, 347), emepụta kwesịrị họrọ LSi grade.LSi fillers nwere obere carbon ọdịnaya (0.02%) na-Ya mere karịsịa na-atụ aro mgbe e nwere ihe ize ndụ nke intergranular corrosion.Higher silicon ọdịnaya na-enyere wetten na flafusion dị ka wetten na-eme ka ihe ndị dị otú ahụ na-eme ka wetten na-eme ka okpueze na-eme ka ọ dịkwuo mma. e.
Ndị na-emepụta ihe kwesịrị ịkpachara anya mgbe ha na-eji usoro nnyefe nke dị mkpirikpi. Njikọ na-ezughị ezu nwere ike ịkpata n'ihi na-ekpochapụ arc, na-eme ka usoro sub-par maka ngwa dị oke egwu. N'ọnọdụ dị elu, ọ bụrụ na ihe ahụ nwere ike ịkwado ntinye ọkụ ya (≥ 1/16 inch bụ ihe dị ka ihe na-esi ísì ụtọ welded site na iji ọnọdụ ịgba chaa chaa pulse), a na-ahọrọ pulse na-ahọrọ ebe ọ ga-enyefe ebe a na-ahọrọ ịgbanye GMA. na-enye ngwakọta na-agbanwe agbanwe.
Ndị a elu okpomọkụ nyefe ụdịdị adịghị achọ Ọ na-echebe gas.N'ihi ịgba ịgbado ọkụ nke usoro 300 usoro alloys, a nkịtị nhọrọ bụ 98% Ar na 2% reactive ọcha dị ka CO2 ma ọ bụ O2.Some gas ngwakọta nwekwara ike ịnwe obere ego nke N2.N2 nwere elu ionization ikike na thermal conductivity, nke na-akwalite wetting na-enye ohere maka ngwa ngwa njem ma ọ bụ mma;ọ na-ebelatakwa mgbagọ.
N'ihi na pulsed ịgba nyefe GMAW, 100% Ar nwere ike ịbụ ihe na-anabata nhọrọ. N'ihi na pulsed ugbu a stabilizes na arc, gas anaghị achọ mgbe niile ọcha ọcha.
Ọdọ mmiri a wụrụ awụ na-adị nwayọọ maka ferritic igwe anaghị agba nchara na duplex igwe anaghị agba nchara (50/50 ratio of ferrite to austenite) .N'ihi na ndị a alloys, a gas ngwakọta dị ka ~ 70% Ar / ~ 30% He / 2% CO2 ga-akwalite mma wetting na-amụba njem ọsọ (lee Figure 3) yiri ngwakọta nwere ike iji weld na nickel alloys n'elu, ma will oxide na-eme ka% nickel. CO2 ma ọ bụ O2 zuru ezu iji mee ka ọdịnaya oxide dịkwuo elu, ya mere ndị na-emepụta kwesịrị izere ha ma ọ bụ dị njikere itinye oge dị ukwuu na ha).Abrasive n'ihi na oxides ndị a siri ike nke na brush waya anaghị ewepụ ha).
Ndị na-emepụta ihe na-eji eriri igwe anaghị agba nchara flux maka ịgbado ọkụ na-apụ apụ n'ihi na usoro slag na wires ndị a na-enye "shelf" nke na-akwado ọdọ mmiri weld ka ọ na-eme ka ọ dị ike. , Ọ bụ ihe kwesịrị ịrịba ama na elu niile-ọnọdụ ịgbado ọkụ ọsọ na deposition ọnụego nwere ike ibelata mkpokọta ịgbado ọkụ na-akwụ ụgwọ.Na mgbakwunye, na flux-cored waya na-eji a ot mgbe niile voltaji DC mmepụta, na-eme ka isi ịgbado ọkụ usoro obere ọnụ na obere mgbagwoju karịa pulsed GMAW usoro.
N'ihi na 300 na 400 usoro alloys, 100% Ar na-anọgide na ọkọlọtọ nhọrọ maka gas tungsten arc welding (GTAW) .N'oge GTAW nke ụfọdụ nickel alloys, karịsịa na mechanized usoro, obere ego nke hydrogen (ruo 5%) nwere ike na-agbakwunyere obere ego nke hydrogen (ruo 5%) na-amụba njem ọsọ (rịba ama na n'adịghị ka carbon steels, nickel alloys adịghị adị mfe).
Maka ịgbado ọkụ superduplex na superduplex igwe anaghị agba nchara, 98% Ar / 2% N2 na 98% Ar / 3% N2 bụ ezi nhọrọ, karị.Helium nwekwara ike na-atụkwasịkwara ka melite wettability site banyere 30% .Mgbe ịgbado ọkụ super duplex ma ọ bụ super duplex igwe anaghị agba nchara, ihe mgbaru ọsọ bụ na-emepụta a nkwonkwo na a kwesịrị ekwesị microstructure na% ferrite nke mkpokọta 30% . microstructure na-adabere na ọnụ ọgụgụ dị jụụ, na n'ihi na ọdọ mmiri TIG na-ekpo ọkụ ngwa ngwa, oke ferrite na-anọgide mgbe a na-eji 100% Ar. Mgbe a na-eji ngwakọta gas nwere N2, N2 na-akpali n'ime ọdọ mmiri a wụrụ awụ ma na-akwalite nhazi austenite.
Igwe anaghị agba nchara kwesịrị ichekwa akụkụ abụọ nke nkwonkwo ahụ iji mepụta weld gwụchara nke nwere oke nguzogide corrosion. Ịghara ichekwa azụ azụ nwere ike ịkpata "saccharification," ma ọ bụ nnukwu oxidation nke nwere ike iduga ọdịda solder.
Tight butt fittings na anọgide magburu onwe kwesịrị ekwesị ma ọ bụ uko containment na n'azụ nke kwesịrị ekwesị nwere ike ọ gaghị achọ nkwado gas. Ebe a, isi okwu bụ iji gbochie oké discoloration nke okpomọkụ-emetụta mpaghara n'ihi oxide ewu-elu, nke mgbe ahụ na-achọ mechanical removal.Technically, ma ọ bụrụ na backside okpomọkụ karịa 500 degrees Fahrenheit, a na-echebe gas na-achọrọ na-eji ihe ọ bụla. jide.Ideally, nkwado kwesịrị ịdị n'okpuru 30 PPM O2. Ewepụghị bụ ma ọ bụrụ na azụ nke weld ga-gouged, ala na welded iji nweta a zuru penetration weld.
Ihe abụọ na-akwado gas nke nhọrọ bụ N2 (dị ọnụ ala) na Ar (dị ọnụ ahịa) .N'ihi na obere mgbakọ ma ọ bụ mgbe isi mmalite Ar dị ngwa ngwa, ọ nwere ike ịdị mfe iji gas a na-abaghị uru na N2 ego. Ruo 5% hydrogen nwere ike ịgbakwunye iji belata oxidation.A dịgasị iche iche nke azụmahịa nhọrọ dị, ma n'ụlọ nkwado na-adị ọcha dams.
Mgbakwunye nke 10.5% ma ọ bụ karịa nke chromium bụ ihe na-enye igwe anaghị agba nchara ya igwe anaghị agba nchara. Ijikwa ihe ndị a chọrọ usoro dị mma n'ịhọrọ ezigbo ịgbado ọkụ na-echebe gas na-echebe azụ azụ nke nkwonkwo. ọkachamara mgbe ị na-ahọrọ gas na ndochi igwe maka ịgbado ọkụ igwe anaghị agba nchara.
Jikọọ akụkọ, ihe omume na teknụzụ kachasị ọhụrụ na ọla niile sitere na akwụkwọ akụkọ anyị kwa ọnwa abụọ edere naanị maka ndị na-emepụta Canada!
Ugbu a site na ịnweta mbipụta dijitalụ nke Canadian Metalworking, ọ dị mfe ịnweta akụrụngwa ụlọ ọrụ bara uru.
Ugbu a site na ịnweta mbipụta dijitalụ Mere in Canada na Welding zuru oke, ịnweta akụrụngwa ụlọ ọrụ bara uru dị mfe.