Abstract: The loose coil problem was a common problem in hot steel coil bundling, which seriously affected the transportation safety and product quality of steel coils. The detailed processes of hot steel coil bundling were analyzed, and the temperature difference between steel coils and steel strap was pointed out as the main reason for the problem of loose coil. Therefor a delay locking buckle technology was proposed. The pre-heating of the steel straps was achieved through the delay locking buckle. The steel coil were no longer loose in cold state by controlling the minimum bundling force for secondary tightening. The pre-heating time was calculated, and the calculation formula of the delay locking buckle time was deduced. Based on the analysis of the relative deformation of the steel coil and the steel strap, the minimum bundling force for secondary tightening was determined on the premise of ensuring the standard residual bundling force. Experiments were performed on the automatic bundling machine using the delay locking buckle technology, and the results show that the technology may effectively solve the problem of loose strap and improve the quality of steel coil bundling.

Key words: steel coil bundling, delay locking buckle；pre-heating, secondary tightening

摘要： 松卷问题是热轧钢卷打捆的常见问题，严重影响钢卷的运输安全和产品质量。分析了钢卷热态打捆的详细过程，指出钢卷和捆扎钢带的温度差是产生松卷问题主要原因，并据此提出了延迟锁扣技术。通过延迟锁扣实现了捆扎带的预加热，通过控制二次收紧最小捆扎力保证了钢卷冷态时不松卷。对预加热时间进行了理论计算，并推导出延迟锁扣时间的计算公式，通过对钢卷与捆扎带相对变形量的分析，在保证捆扎带标准残余捆扎力的前提下，确定了二次收紧最小捆扎力。使用延迟锁扣技术在自动打捆机上进行了实验，结果表明该技术可以有效解决捆扎带松散问题，提高钢卷打捆质量。

关键词: 钢卷打捆, 延迟锁扣, 预加热, 二次收紧