SafetyCâu 101 / 110
A 2,000 lb cast-iron section is lifted by a two-leg sling with each leg at 60 degrees from horizontal. Each leg carries (load / 2) / sin(60 degrees), with sin(60) about 0.866. What is the tension in each sling leg?
a.1,155 lb
b.1,000 lb
c.1,414 lb
d.2,000 lb
Giải thích
Each leg tension = (2,000 / 2) / 0.866 = 1,000 / 0.866 = 1,155 lb. As the sling angle drops toward horizontal, the leg tension climbs above the simple share of the load, which is why slings must be de-rated for angle. At a straight vertical lift each leg would carry only 1,000 lb.
Trích dẫn luật: 29 CFR 1926.251Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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