|
A cranked eye bolt is an eye bolt typically used as a structural tie down 〔Note: Tie down: As part of a system of interacting components to secure the building, from the roof down to the footings, to the foundation material〕 in building construction where the eye of the bolt must be fastened to a point that cannot be directly below where the shaft would otherwise be fastened. This often occurs where a bearer must be tied down to a post or column but the bearer cannot be directly fastened to the post of column. It has a shaft which is ''cranked'', or bent twice: once off center, and a second time to bring the shaft back parallel to the original shaft. ==Uses== The requirement for an offset tie down will occur when vermin proofing must be placed between the column or post, and a wooden bearer, for example to stop termites travelling up through a concrete or wooden post or column directly into the bearer and the rest of the building. The "ant capping", typically a 0.5mm to 0.8mm thick galvanised steel sheet, must be placed between the post and the bearer overlapping the perimeter of the post by approximately 20mm to 40mm or more. The cranked eye bolt is fastened to the post using a bolt though the eye, the crank in the shaft allowing the shaft to be positioned so that it does not impede the overlap of the "ant capping" up through the bearer. Should termite attack occur, the post of column can be replaced with no structural effect to the building. Cranked eye bolts can also be used to tie the top plate of a house frame directly to house supports, using rod couplers and steel extension rods. Image:Welded eye cranked bolt in situ.jpg|Welded eye cranked bolt tying down bearer Image:Welded eye cranked bolt in situ top plate.jpg|Welded eye cranked bolt with coupling rod to (not shown) frame pitching plate and top plate 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cranked eye bolt」の詳細全文を読む スポンサード リンク
|