基于斜抛物线法的空钩下降能力分析研究  

On descending ability of empty hook based on oblique parabola method

作　　者：聂宁 Nie Ning

机构地区：[1]上海电气风电集团股份有限公司,上海200235

出　　处：《起重运输机械》2023年第5期23-29,共7页Hoisting and Conveying Machinery

摘　　要：文中基于斜抛物线法从空钩下降的基本条件出发,将下降临界条件建立前后悬垂段钢丝绳的弧长差值及其时间增量作为浮式起重机空钩下降能力的衡量指标。通过改变挠跨比、空钩自重、钢丝绳线密度、速度曲线性能指标等参数,定量分析和考察其对空钩下降能力的影响。结果表明:悬垂段钢丝绳弧长的变化量、卷筒放绳量、放绳时间可以直观并有效地描述空钩的下降能力,适当地提高挠跨比、增加吊钩组自重或减小钢丝绳线密度会更利于空钩的下放。在较大幅度或水平跨度位置处的放绳量增加显著,空钩下降能力趋弱,据此条件所设计的吊钩组自重同时也能满足其他较小幅度或水平跨度下对空钩下放的要求。分析对比不同速度曲线影响下放绳量和放绳时间的变化,发现放绳量对加、减速度变化的敏感度较弱,以放绳时间去描述空钩的下降能力或下放效率将更为合理。Based on the oblique parabola method, under the basic condition of empty hook descent, the arc length difference and its time increment of the suspended wire rope before and after the establishment of the critical condition of descent are taken as the measurement index of the empty hook descent ability of floating crane. By changing the parameters such as the torsion span ratio, the dead weight of the empty hook, the linear density of the wire rope and the performance index of the speed curve, the influence on the descending ability of the empty hook is quantitatively analyzed. The results show that the variation of wire rope arc length, amount of rope released by drum and the rope release time can directly and effectively describe the descending ability of empty hook, and it is more beneficial to lower empty hook by appropriately increasing the torsion span ratio, increasing the dead weight of hook group or reducing the linear density of wire rope. At the position of larger amplitude or horizontal span, the amount of rope released increases significantly, and the descending ability of empty hook becomes weak. The self-weight of hook group designed according to these conditions can also meet the requirements of lowering empty hook at other smaller amplitude or horizontal span. By comparing the changes of rope release amount and time under the influence of different speed curves, it is found that the sensitivity of the amount of rope released to speed change is weak, and it is more reasonable to use rope release time to describe the lowering ability or lowering efficiency of empty hook.

关 键 词：浮式起重机 斜抛物线法 放绳量 放绳时间 空钩下降 

分 类 号：U674.35[交通运输工程—船舶及航道工程]