Chinese (zachikhalidwe)

Incluloy Anoy 800 ndi chovomerezeka cha nickel, chitsulo ndi chromium. The Alloy amatha kukhala wokhazikika komanso kusungitsa mawonekedwe ake pa nthawi yayitali akutulutsa kutentha kwambiri. Makhalidwe ena a AloY ndi mphamvu zabwino, komanso kukana kwambiri kukomoka, kuchepetsa ndi kuwongolera madera

Chitsito chopanda maziko cha 316 chakhala chinthu chofunikira kwambiri kwa gawo la mafakitale. Chitsulo ichi ndi chrome chimadziwika kuti ndikukana kwake kuvunda, komanso kukhazikika kwake. 316 Chitsulo chosapanga dzimbiri chimatha kupangidwa muzosaso komanso machubu owuma kuti akwaniritse zosowa zapadera za kasitomala.

Bolt mtundu wopapatiza wocheperako B18.21.1 A320 L7M Hex Bolt Anoy Bolt
Sch40 Monol 400 chitoliro chimasankhidwa kukhala nambala ya Werkstoff 2.4360 ndi N04400. Chipika 400 chimadziwikanso kuti Monil Anoy chitoliro cha 400, Monl 400 Pipe & Nickel Chitoliro 400.
Monl 400 SI04400 1 \ / 2 "kalasi 150 rf

Amagwiritsidwa ntchito kwambiri mu zopondaponda m'mafuta ndi mafuta a gasi \ / kupanga ndi kusinthidwa kwa kutentha mu petrochemical \ / mankhwala.

Nickel kutengera 800 inclooy chitoliro chomwe chimadziwika kuti ndi kukana bwino kuwonongeka. Makamaka kuyankhula, chisumbulu 800 chitoliro chimapereka kukana mokwanira zotsutsana ndi ma carburization onse komanso oxidation kutukula.

The? Astm A182 F304? Itha kutsukidwa mosavuta ndi chotchinga chofatsa. Ngakhale akusintha mobwerezabwereza, zowoneka bwino zopambana, kuthekera kumawonetsa chifukwa chake kuvala bwino. Komanso, kuyambira giredi 304 ndiloyamwa zomwe zingapangitse mosavuta mawonekedwe, imapangidwa mosavuta mu mtundu uliwonse wa mtundu wa strenge kapena.

Onse a Sa234 WPB Erdow adapangidwa ku India ndikupangidwa kuchokera ku Europe yoopsa ku Europe. Onse a Astm A234 Elbow & Erbow A234 WPC amapangidwa kuchokera mbale, atapanikiza mbali ziwiri ndi ma halves awiri.
Chitsulo chosapanga dzimbiri cha Al-6xn Tube Asme Sb 676 SIM SI08367 BUT

Incoloy Aloy 800 imagwiritsidwa ntchito kwambiri m'matodi omwe ayenera kukhala ndi mphamvu zambiri komanso kukana kwa oxidation, ndalama zina ndi zovuta zina zamagetsi.

Zimawonetsa kukana bwino kusalowerera ndale. Izi za alloy zimapanga mwa khumi ndi chimodzi, filimu yoteteza yomwe siyitalikirapo, koma imasunganso kukana kwa makutina kuposa kutentha.

Asme B36.19M ndiye wofanana ndendende ndi mapaipi achitsulo osapanga dzimbiri, zomwe zimafotokoza kukula kwake, kulolerana, ndi zomwe amapanga maenda owala komanso osaka.

Njira yokhazikitsa kwa osapanga dzimbiri za 304 chifukwa chotchingira chikakhala chosavuta. Choyamba, chitoliro chimakhala chokonzedwa ndikuchiyeretsa ndikuwonetsetsa kuti 1.4301 Flange ndiopanda kuwonongeka ndi zinyalala. Kenako, a S30400 imakhazikika pa chitolirocho ndipo ogwirizana kuti awonetsetse kuti madziwo kapena gasi. Pomaliza, ma bolts amalimbikitsidwa kwa wopanga wopanga kuti atsimikizire kuti kulumikizidwa, kusamala kuti usathetse ma bolts chifukwa izi zitha kuwonongeka kwa chitoliro kapena chitoliro.

Incluloy ma exoloy floess asme B16.5 Ndife opanga & kutumiza kunja kwa anyezi a B564 infoloy. 800.

Nilo Anoy 36, w.NR 1.3912, Inciar 36 ® ndi chitsulo chotsika kwambiri chomwe chili ndi 36% Nickel ndipo ali ndi gawo la kufalikira kwa gawo limodzi la chitsulo cha kaboni pafupifupi.

Zizindikiro za ASTM A194 zimavala kaboni, zitsulo ndi zosapanga zitsulo zokhala ndi zosapanga zokongoletsera kwambiri komanso \ / kapena kutentha kwambiri. American National Standard SUX SUX Germation (ANA B 18.2.2) idzagwiritsidwa ntchito pokhapokha zitatchulidwa. Mafuta osaposa 1 inchi wotsatsa a Nomwenal adzagwirizana ndi kalasi yodutsa 2b.

FOSTELOLEY X Malawi-ma chromium-nickel iron Molybdenum Super Alloy zolimbitsa thupi zomwe zimakhala ndi kusinthana.

316l 1.4401 s31603 Chipika chosapanga dzimbiri ndi njira yolimba komanso yolimba yofananira yomwe imagwiritsidwa ntchito pazosiyanasiyana za mafakitale ndi malonda. Izi s31603 chitoliro chimapangidwa kuchokera pazinthu zapamwamba za 316l osapanga dzimbiri mosapanga dzimbiri mosapanga chipongwe, oxidation ndi chomata, zomwe zimapangitsa kuti zikhale zabwino m'malo mwazinthu zovuta kapena zovuta.

Zizindikiro za Nickel-Copy-Copy 400 monol 2.4360 molunjika rod ndiyabwino kwambiri opsinjika ku chloride ku chloride movutikira mukakumana ndi zowononga m'matumbo. Monl 400 ndi a Haloy ndi Nickel omwe amadziwika masiku ano chifukwa cha ntchito yake yayitali. Alloy ali ndi kukana bwino acid ndi alkali. Kuphatikiza apo, ili ndi mphamvu zabwino zokhala ndi mphamvu, duckity, kukhala waulimi wabwino kwambiri, ndipo imatha kuumitsidwa ndi ntchito yozizira. Kuphatikiza apo, itha kugwiritsidwa ntchito poizona ndi kutentha kuyambira kuchotsera mpaka 538 digiri Celsius.

ASTM B462 SI08020 SIYANI PA Flange Alfic Ads 20% Kukana Ma asidi Otentha Kwambiri Pagerogration Acids, komanso Asul Salfuric Acid Kukana.

Imatha kupirira mankhwala osiyanasiyana osakhazikika komanso osasinthasintha, ndikuwonetsa kukana kwakukulu ndikumenya ndi Crevice pamaso pa chlorides ndi ma halides ena.

Monl 400 STR4400 1 \ / 2 "Class 150 RF MOUNTO 400 FORS ikuwonetsa umboni wa kutentha kwambiri. Kumbali inayo, katundu monga nyonga ndi kuuma kwa magetsi a Monl 400 amangochepetsedwa pang'ono ndi zinthu zina ngati maulendo ena kapena kukana.

Nthawi zambiri N08367 imatchedwanso Al6xn Al6xn ndi kaboni yotsika, yoyera kwambiri, nulytel-molybdenum yolimbana ndi crevice.

Asme B36.19M Chitoliro chosapanga dzimbiri
Chromium yapamwamba, molybdenum ndi nayitrogeni imapangitsa kuti zikhale bwino kwambiri (zomwe zingachitike) zitsulo zokongoletsera ndi zotupa zosapanga dzimbiri, komanso kutentha kotsika kwambiri kuposa 50¡c.

FSTEOLLOY C2000 ikupezeka mu mitundu yosiyanasiyana ndi makulidwe amtunduwu, mtundu uwu wa chromium-molybdenum aroyoy amadziwika bwino chifukwa cha mphamvu zake zazikulu komanso kukana.

FOSTELOLELOY B3 Wakhungu wakhungu ali ndi malo abwino, ndi oxidation¡¯s kukana. FOSTELOLELOY B3 weld Thorts Flanges Slanges Slanges Isn¡¯t yolimbikitsidwa kuti igwiritsidwe ntchito pamaso pa Ferric kapena Cupric Oyendetsa Madzi chifukwa oyendetsa sitimawo amatha kubweretsa kulephera kosavomerezeka.

Alloy 800 ndi a nickeum-chromiam almoy mphamvu ndi mphamvu yayikulu komanso kukana kwa oxidation ndi kutupa kwambiri. ASTM B407 SINE N08800 infoloy 800 WR. 1.4876 Chitoliro chowala bwino chimagwiritsidwa ntchito kwambiri pomanga zida zofuna kukana kuchuluka, kukana kutentha, mphamvu, komanso kukhazikika pakuchita nawo ntchito mpaka 1500 ° C).

Incrooy 800h Valnge Tili ndi mbiri yolimba mu malonda popanga mitundu yayikulu ya mitundu yosiyanasiyana ya makasitomala athu. Timakhala ngati infolisoy ma fronges omwe ndi odalirika komanso apamwamba kwambiri. Timagwiritsa ntchito ndalama zotsogola komanso makina apamwamba popanga assowm B564 SIMIL N08800 Stuliloy ma fronges 800.

Inter 36 ® ndi chitsulo-chitsulo chotsika kwambiri chomwe chili ndi 36% Nickel, IMPARS 36 ili ndi zochulukirapo pakukula kwa kutentha kwa a Crogenic pafupifupi + 260 ° C).

Al6xn ndi chitsulo chosapanga dzimbiri chosakhazikika ku chloride pansi, crevice kutukuka komanso kupsinjika kuwonongeka. Al6xn ndi Alloy a 6 wokhazikika womwe umapangidwa ndipo umagwiritsidwa ntchito m'malo ovuta. Ili ndi Nickel (24%), Molybdenum (6.3%), nayitrogeni ndi chromium yomwe imapangitsa kuti zisautso, chloride pansi. Al6xn imagwiritsidwa ntchito makamaka pokana zolimba komanso zopondera ku chlorisi. Ndi chitsulo chosapanga dzimbiri.

Pambuyo pakuyesa kwakanthawi kochepa komanso kuyesa pang'ono pang'onopang'ono, kugwedeza chitoliro cha sewn chimapezeka kutali kwambiri ndi malo owotcha kapena malo owiritsa. Izi ndichifukwa choti chosawoneka bwino komanso chidebe cha nayitrogeni chimakwera pang'ono, motero mphamvu ya mawolo abwino kuposa zigawo zina.

Ma coil 625 amadziwika ndi kukana kwake kwabwino kwa oxidation, kutentha kwambiri komanso kutopa. ASTM B443 SANDO N06625 SIVELEILE imagwiritsidwa ntchito kwambiri mu anthospace, mankhwala kutengera ndi mafuta ndi mafakitale chifukwa champhamvu kwambiri.

ASTM A240 Mtundu 2205 Plate ndi duwa losapanga dzimbiri lomwe limagwiritsidwa ntchito kwambiri m'mafakitale, kufufuza kwamafuta ndi mafuta, ndi ukadaulo wamadzi, ndi ukadaulo wamadzi. Mapepala 2205 amapangidwa kuchokera ku kalasi ya SAGIS 2205, chitsulo chosapanga dzimbiri, chomwe chimaphatikizika ndi chitsulo champhamvu.
Carbon zitsulo zowongoka
Diameter 5 ~ 500mm
Mixembaurgish
304 Road Bar
Chitchaina (chosavuta)
Illevesel Pipe Natioxidant Kukana
1 mpaka 72 inchi enbon carbon chitsulo chamiyala
Carbon Steel Bars & ndodo
Duptux Stevel & Mapepala & Coils
Kutchuka kwakukulu kwa mipiringidzo yachitsulo kuli ndi ngongole yoti
Carbon Steel Asme Asme Sa 234 WPB 180 Deger Break

Asme B16.9 ndi muyezo wodziwika bwino m'makampaniwo kuti azigwiritsa ntchito moyenera, zopondera, ndi zigwa zomwe zimagwiritsidwa ntchito pamapaipi. Zogwirizana za kukula kwazithunzizi, kulolera, zida, ndi zolemba zamitundu yosiyanasiyana ya zinthu. Katundu wina wogwiritsidwa ntchito kwambiri ndi chipongwe, ndipo a234 wpb nthawi yayitali a rabius carbon chitsulo ndi chisankho chotchuka.

304 Nphwemba zopondapondazikulu zimapangidwa ndi chitsulo chosapanga dzimbiri, zinthu wamba komanso zodziwika bwino muzogwiritsidwa ntchito zambiri zamakampani zomwe zimafunikira kukana kuwonongeka ndi oxidation. Nyansiweli iyi ya S30400 imakonzedwa pogwiritsa ntchito makina apadera ndi njira, zomwe zikuwonetsetsa kuti ndi olondola komanso odalirika.
Carbon zitsulo zowongoka
Diameter 5 ~ 500mm
Mixembaurgish
304 Road Bar
Chitchaina (chosavuta)
Illevesel Pipe Natioxidant Kukana
1 mpaka 72 inchi enbon carbon chitsulo chamiyala
Carbon Steel Bars & ndodo
Duptux Stevel & Mapepala & Coils
Kutchuka kwakukulu kwa mipiringidzo yachitsulo kuli ndi ngongole yoti
Carbon Steel Asme Asme Sa 234 WPB 180 Deger Break

Ictives 600 yozungulira ndi intoy-valkel-brad-cenel carburrization ndi kukana bwino kuwonongedwa kwakukulu. Zingwe zozungulira 600 zozungulira zimagwira ntchito kuyanika cl2 ndi mipweya ina yambiri yofananira ndi kutentha kwambiri. Alloy 600 bar ndi a chromial-cromiyal-cromiyal-cromiyal-chloride bwino oxidation ndi kukana ku chloride kuwonongeka kwa chloride kugwa, ukhondo wamadzi acid kumatentha.

Timapereka mitundu yambiri ya Asther A182 F12 Alloy chitsulo chozungulira kuti musankhe, ndipo mipiringidzo yopangidwayi imatha kusinthidwa malinga ndi zomwe makasitomala amafunikira. Amagwiritsidwa ntchito kwambiri komanso magawo ena chifukwa cha ntchito zawo zabwino komanso zosayerekezeka.

FOSTEOLLOY X Chikuto chopanda chitoliro cha N06002 chitoliro cha zikopa za mafakitale ndi kutentha kotentha

Duplex 2205 amalimbitsa thupi amakhala ndi mphamvu kwambiri komanso kuuma pomwe amakhalanso ndi mphamvu yayikulu, zonse chifukwa cha chromium. Komabe, zitha kupezeka kuti gawo lachiwiri la zitsulo zoyeserera sizimatsutsidwa; Sanawononge kapena kuwonongeka. A Chomaly uyu ndiosavuta kuchitika. 2205 Mawonda othamanga amadya mapangidwe owoneka bwino opangidwa ndi zitsulo zosakhazikika zopangidwa ndi zitsulo zosakhazikika zopangidwa ndi chitsulo chomwe chimadziwika kuti ndi gawo la chotupa, ndipo zotsatira zake zimakhala zolimbitsa thupi mokweza ma duple.

ASTM A182 F304 kotero kuti amapondaponda pang'ono pa 304 osapanga dzimbiri zomwe zatulutsidwa

Al-6xn alloy idapangidwa kuti ikhale zinthu zosagwiritsidwa ntchito ndi madzi ndipo zawonetsedwa kuti zigwirizane ndi malo ochulukirapo.

ASMM B564 SIMPOOY 800 ndi Nickel-Chromial-Cromioy Alloy yomwe imapereka mphamvu kwambiri komanso kukana kwa oxidation ndi kuchapa kwambiri.

M'mapulogalamu apamwamba kwambiri a ndege, chromium ndi mtundu wa mbewa zosapanga dzimbiri umagwiritsidwa ntchito chifukwa cha kutentha kwawo ndi kukana kwa chiwombolo. Wopezeka mu mapulogalamu omwe amafunikira ndege zapamwamba kwambiri, ndege zosapanga dzimbiri zimatha kugwira ntchito kapena kuwotcha, ngakhale kuti zidutswa zolimba ntchito zosakhazikika zimagwiritsidwa ntchito ndi mitundu ina ya zinthu. Mitundu yotsika-carbon ya chitsulo chosapanga dzimbiri ndi chisankho wamba cha magawo owala.
Carbon zitsulo zowongoka
Diameter 5 ~ 500mm
Mixembaurgish
304 Road Bar
Chitchaina (chosavuta)
Illevesel Pipe Natioxidant Kukana
1 mpaka 72 inchi enbon carbon chitsulo chamiyala
Carbon Steel Bars & ndodo
Duptux Stevel & Mapepala & Coils
Kutchuka kwakukulu kwa mipiringidzo yachitsulo kuli ndi ngongole yoti
Kuimbira 36: Opanda K93600, W.NR 1.3912

Kuchulukitsa kwa titanium ndi pafupifupi 60% yomwe ya chitsulo chosapanga dzimbiri ndi nickel polosys, kupulumutsa thupi kumeneku kumapangitsa kuti ikhale chisankho chodziwika bwino pakugwiritsa ntchito monga Arrospace.

Kuphatikizidwa kwa mankhwala a Montin K500 Asther ali pafupifupi 65% Nickel, 30% mkuwa ndi 3% aluminiyamu. Monl 500 Ziwonetsero Zabwino Kwambiri Kukana ndi mphamvu yayikulu yowonjezera kutopa ndi kukokoloka. Motele K500 Makina osagwirizana ndi magwera kwambiri komanso otsika. Zinthuzo zili ndi vuto lomwelo monga kalasi ya Montel 400.
Diameter Kulekerera H7 H9 H10 H11
Diameter 5 ~ 500mm
Mixembaurgish
304 Road Bar
Chitchaina (chosavuta)
Illevesel Pipe Natioxidant Kukana
ASME A240 Mtundu 2205 Drite Stockgerder SA 240 GRE 2205
Carbon Steel Bars & ndodo
Duptux Stevel & Mapepala & Coils

A234 WPB ANA B16.9 ASTM Caboni chitsulo cha 30d 4D 45D 90D Sch20 Sch20 Sch80 SCH40 SCOM SHAMP

Mtundu wa 316 wosapanga dzimbiri umagwira ntchito makamaka mu wowawasa. Kalasi iyi yachitsulo imagwira ntchito motsutsana ndi kuwonongeka kwa sulfuric, hydrochloric, acerochloric, acerochloric, acitic ndi tartic acids, komanso chloric yoyambira.

Nickel 200 Amalongosola Nickel 200 Malawi amakhala olimba, osasunthika, ndipo amaliza bwino. Kuphatikiza apo, Astm B564 SP52200 N02200 Zisoka zakhungu zimalimbana ndi kutengera ndale komanso zotsatsa, zimapangitsa kukhala bwino kugwiritsa ntchito zida zogwirizira.
Carbon zitsulo zowongoka
Diameter 5 ~ 500mm
Mixembaurgish
304 Road Bar
Chitchaina (chosavuta)
Illevesel Pipe Natioxidant Kukana
1 mpaka 72 inchi enbon carbon chitsulo chamiyala
Carbon Steel Bars & ndodo
Duptux Stevel & Mapepala & Coils
Kutchuka kwakukulu kwa mipiringidzo yachitsulo kuli ndi ngongole yoti
Duptux Steel S31803 SPIPES SIPS

Bardenti yachitsulo yopanda dzimbiri imapereka mitundu yosiyanasiyana ya mafakitale ambiri ndi ntchito padziko lonse lapansi. Ubwino wa bar wopanda banga umaphatikizapo moyo wachinyamata, kukana kwa moyo wautali, mawonekedwe owoneka bwino, mawonekedwe owoneka bwino opanga, kukana ndi mtengo wautali. Zitsulo zosapanga dzimbiri ndi imodzi mwazitsulo zomwe zimagwiritsidwa ntchito kwambiri pomanga masiku ano.

Kuchuluka kwa zinthu zina zomwe zingakhalepo mu chitsulo chosapanga dzimbiri sikufalikira ndi chitsulo cha kaboni. Chinthu chodziwika bwino cha chitsulo chosapanga dzimbiri ndikuti sizophweka kunyamula kapena dzimbiri. Kupewa kuwonongako ndi chinthu chapadera chachitsulo, zitsulo zofatsa zambiri zimapangidwa ndi chitsulo, zomwe zimapangidwa mwachangu atadziwitsidwa ndi mpweya wamba wokhala ndi mpweya wabwino.

Iswees osawoneka bwino kwambiri a sing'anga osawoneka N06600 ndi Astm B167 ndi omwe amapangidwa kuti apirire kwambiri ndikubwera ndi chitsimikizo chachikulu.

Ictives 601 (ONSE N06601) Nickel Basin Inloy ndiyosavuta kuntchito yotentha. Kutentha kutentha ndi 1150 ~ 1200c, ndi kutentha kwa matenthedwe ndi

Kugonjetsedwa kwa Prososion Fretelloy kumagwiritsidwa ntchito kwambiri ndi mafakitale a mankhwala. Kufunika koyenera kumabweretsa mwayi wovomerezeka ndi mphamvu zawo, thanzi komanso zachilengedwe, mafuta ndi mpweya, mafakitale a mankhwala osokoneza bongo.

Izi zimathandizira kuthana ndi sulufuric acid. Ilinso ndi mawu apamwamba kwambiri, kuti apititsenso kukana kwake kuti athe kugwiritsa ntchito mankhwala ndi njira zomwe zimapangidwa ndi mitsinje yolimba ndi mpweya wosungunuka.

Chizindikiro ichi cha Nickel chidapangidwa kuti chizikhala kutentha kwa Crortologenic kuti chitenthe kutentha kwa 1090¡c (2000¡f).

S32750 Super Duplex Coil Chech Scannger 1.4410 1.4501 Coil

Pofuna kufafanizira mapaipi, ndikofunikira kuchotsa payipi yolunjika pa mapaipi. Mukamagwiritsa ntchito ma piipelines osiyanasiyana, mapaipi osiyanasiyana ayenera kugwiritsidwa ntchito. Pamene mapaipiwo amagwiritsidwa ntchito, chikopa chiyenera kugwiritsidwa ntchito kusintha kukula kwa mapaipi. Mukamacheza, chipika chanjira zitatu chowonekacho chimagwiritsidwa ntchito ngati cholumikizira cholumikizira, kuti chikhazikitse chipani cholumikizirana kapena kukula kwa nthawi yayitali komanso cholumikizira cholumikizira cha mapaipi. , Pakulumikizana ndi zida zosiyanasiyana, palinso zolumikizira ndi mapulagini a gawo la chida.

ASME A234 WPB ERAWH ndi gawo lokhazikika pakupanga zolimbitsa thupi za zitsulo za kaboni ndipo alloy amayenera kutentha kwa kutentha komanso kwakukulu.

Duptux Steel S31800 S31802 SPIPS SIPSS imagwiritsidwa ntchito kwambiri pamagulu osiyanasiyana m'makampani. Izi Astme A790 Duplex Steple S31803 Mapaipi amapangidwa ndi kuphatikiza microstructuctuctuctuctuctuctuctucestection ya Austetic ndi Mbewu zachangu, zomwe zimawapatsa iwo malo ena. Izi zimaphatikizapo kukana kwambiri kuwonongeka, mphamvu zabwino kwambiri komanso kulimba mtima, komanso kusamva bwino.

Nickel Anoy 400 ndi Monl 400, omwe amadziwikanso kuti ndi N04400 Nictal-Copy-Copy-Copy kukhala makamaka mwa atatu a Nickel ndi chachitatu. Nickel Anoy 400 amadziwika chifukwa chokana kusiyanasiyana, kuphatikiza alkalis (kapena asidi), madzi amchere, ma hydrofluoric acid. Kuyambira monoy 400 kapena Aloy 400 ndi chitsulo chozizira chogwira ntchito, chivomerezichi chimakhala cholimba, kuuma ndi mphamvu. Pogwira ntchito yozizira astm B164 SARD N04400 bar stock, alloy imayang'aniridwa ndi kupsinjika kwamakina, komwe kumapangitsa kusintha kwa micrestructuctuctution ya Alloy.

ASMM A312 TP316 ndi njira yokhazikika ya msoko, komanso kuzizira kwambiri osakhazikika opaleshoni ya chitsulo chosapanga dzimbiri zomwe zimagwiritsidwa ntchito kutentha kwambiri ndi ntchito wamba. Chitoliro chosawoneka bwino mafakitale chimapangidwa kuchokera ku chromium, nickel, ndi molybdenum, omwe amapereka SS Quams Stuam Turnion ku kutukula ndi dzimbiri.

Din933 S32760 ulusi pang'ono chilengedwe stule stucket stucket mutu bolt m32 stud mutu bolt bolt ndi nati s327660 spring bolt