Maphunziro a Black Oxide Double-End 

Giredi 8.8 wakuda waku oxide womaliza ndi zomangira zamphamvu zapakati zokhala ndi ulusi mbali zonse ziwiri zokhala ndi shank center yosawerengeka. Amaphatikiza magwiridwe antchito odalirika (800 MPa tensile mphamvu), chitetezo chandalama cha dzimbiri kudzera mu zokutira zowonda za Fe3O4, ndikuyika kosunthika kwamakina akumafakitale, magalimoto, ndi ntchito zamapangidwe.

1. Gulu la 8.8

Pa ISO 898-1, dzina la "8.8" limatanthawuza mphamvu yokhazikika ya 800 MPa ndi chiŵerengero cha zokolola za 0.8 (zokolola mphamvu 640 MPa). Wopangidwa kuchokera ku chitsulo chozimitsidwa ndi kupsya mtima chapakati pa carbon alloy, Gulu la 8.8 limapereka mphamvu zabwino kwambiri zogulira.

Gulu 1 - Katundu Wamakina Ofunikira (ISO 898-1)

2. Black Oxide Surface Chithandizo

Black okusayidi (Fe3O4) ndi mankhwala kutembenuka ❖ kuyanika 0.5-1.5 micrometer wandiweyani, opangidwa ndi kumizidwa mu otentha zamchere nitrate kusamba pa 140-150C. Mosiyana ndi electroplating, sizimayambitsa kusintha kwamtundu uliwonse komanso palibe hydrogen embrittlement. Ikasindikizidwa ndi mafuta oletsa dzimbiri, imapereka mpaka maola 96 osakana kupopera mchere.

Table 2 - Zida Zovala za Black Oxide

3. Mapeto Awiri a Stud Design

Chitsulo chokhala ndi mapeto awiri chimakhala ndi pompopompo (chotsekedwa mu dzenje lopopera) ndi mapeto a nati (amavomereza nati), olekanitsidwa ndi shank yosawerengeka. Kutalika kwapampopi nthawi zambiri kumakhala 1.0-1.5d ndipo mtedza umatha 2.0-3.0d, pomwe d ndi m'mimba mwake mwadzina.