Dacromet-Coated Hex Bolts

2026-10-27

1. Nhanganyaya

Hex mabhaudhi (hexagon musoro mabhaudhi) ari pakati pezvinonyanya kushandiswa zvisungo mukuvaka, muchina, gungano remotokari, uye zvivakwa. Munzvimbo dzinoparadza - zvivakwa zvemahombekombe, zvirimwa zvemakemikari, migwagwa mikuru, mabhiriji, uye shongwe dzesimbi dzekunze - hupenyu hwesevhisi yejojo yakasungwa kazhinji inotariswa kwete nesimba resimbi, asi nekusimba kwekuvhara kwayo kwekudzivirira.

Dacromet coating (inozivikanwawo seDACROMET, Dacromet zinc-flake coating, kana zinc-aluminium flake coating) ndeyemvura-based conversion-and-barrier coating inoshandiswa nedip-spin kana spray process uye inoporeswa pakupisa kwakadzika. Kubva payakagadzirwa kuUnited States kuma1970s uye kwakazotevera maindasitiri muJapan neEurope, Dacromet yave nzira yekudzivirira corrosion-yekudzivirira-yepamusoro-soro mabhaudhi, kunyanya mumagiredhi 8.8 uye pamusoro, apo yechinyakare inopisa-dip galvanizing inotakura hydrogen embrittlement matambudziko uye dimensional matambudziko.

2. Chii chinonzi Dacromet-Coated Hex Bolt?

Iyo Dacromet-yakavharwa hex bolt ndeye yakajairwa hexagon musoro bhaudhi (pamwe neISO 4014 / ISO 4017 / DIN 931 / DIN 933 kana ASME B18.2.1) iyo nzvimbo yakachengetedzwa ne zinc-flake based coating yakaiswa kubva mumvura-based slurry ine:

Zinc flakes uye aluminium flakes- iyo inoshanda ngura-yekudzivirira barriers (yakajairika chiyero chakatenderedza 75% Zn / 25% Al nezvakasimba zvemukati);
Chromium makomisheni kana chromium-isina passivators- kupa kuzviporesa passivation panzvimbo dzekutanga;
Inorganic binders uye cellulose thickeners- sunga maflakes mufirimu yakaoma, inonamatira;
Deionized mvura- iyo inotakura svikiro, ichiita iyo nzira isina VOC uye ine hushamwari.

Iyo yekuputira inoshandiswa nekunyura (kana kupfapfaidza) ichiteverwa necentrifugal kuruka kuti ibvise slurry yakawandisa, yobva yapora paanenge 280-330 ° C kwemaminetsi makumi maviri kusvika makumi mana. Multiple dip-spin cycles (kazhinji maviri) anovaka coating ukobvu hwe6–10 μm; makirasi anorema anosvika 12-15 μm.

Hunhu Hunokosha hweDacromet process

Feature	Tsanangudzo
Kurapa tembiricha	280–330°C (pasi petembiricha yegiredhi 10.9/12.9 mabhaudhi)
Coating ukobvu	6–15 μm (inotsamira mukirasi), yakatetepa kupfuura kupisa-dip galvanizing (45–85 μm)
Hydrogen embrittlement	Hapana acid pickling, hapana electroplating - inenge isina hydrogen embrittlement njodzi
Hex musoro wakakodzera	Yakatetepa, yakapfeka yunifomu inochengetedza shinda geometry - mabhaudhi matepi nematepi akajairwa
Environmental profile	Mvura-yakavakirwa, hapana VOC inobuda; chromium-isina (Cr³⁺/Cr⁶⁺-yemahara) mhando dziripo
Electrical conductivity	Conductive firimu, yakakodzera kudzika-yakakosha zvimiro

Tafura 1. Hunhu hunokosha hweDacromet coating process.

3. Corrosion Protection Mechanism

Dacromet inodzivirira iyo simbi substrate kuburikidza nematatu ekuwedzera maitiro:

1.Barrier effect- kupindirana kwezinc uye aluminium flakes inoumba firimu rakasvibiswa rine nzira inotambudza iyo inononoka zvikuru kupinda kwemvura, oksijeni, uye chloride ions.

2.Kudzivirirwa kwechibayiro- zinc haina kunaka kupfuura simbi; pane chero kukwenya kana kuchekwa, zinc corrodes zviri nani uye cathodically inodzivirira simbi yakafumurwa.

3.Pasivation / kuzviporesa- mapassivator anoumba insoluble oxide mafirimu panzvimbo dzakakanganisika, "kuporesa" zvikweshwa zvidiki uye kunonoka chena ngura uye tsvuku tsvuku kugadzira.

Iko kusanganiswa kwemaitiro matatu aya kunotsanangura kuti sei Dacromet coatings inogara ichiendesa maawa 500-1,000 kune tsvuku ngura mukusarerekera munyu kupfapfaidza bvunzo (pamwe ISO 9227 / ASTM B117) pakukora kwe6-10 μm chete - kakawanda kuita kweakaenzana-ukobvu electro-galvanizing.

4. Mhedziso

Dacromet-yakavharwa hex mabhaudhi anosanganisa kusimba kwemagetsi ezvivakwa zvakajairwa makirasi 8.8–12.9 ane nhete, yunifomu, haidhirojeni-yakachengeteka, uye inoshamwaridzana necorrosion-protection system. Nekuita kwemunyu kupfapfaidza kakawanda kupfuura electro-galvanizing pane chikamu chehukobvu hwekupisa-dip galvanizing, Dacromet yave iyo yakasarudzika yekumisikidza kune yakakwira-simba zvisungo mukuda kwezvivakwa, simba, uye mapurojekiti ekufambisa.

Kune vatengi nemainjiniya, zvakakosha sarudzo kirasi (hukobvu uye NSS maawa), chromate mhando (Cr³⁺ vs Cr-isina), friction coefficient control, uye kutevedzera ISO 10683 / ASTM F1136. Iyo yakanyatsotsanangurwa Dacromet hex bhaudhi inopa inofanotaurwa, yenguva refu yekubatana kutendeseka - kunyangwe munzvimbo dzakaomarara.

Hauna. Next.