jib arm meaning in English

旋臂

The manual introduced the total design and compute the process detailedly about the general design and the running gear design , which divided into altogether three chapter : chapter 1 for total design part of this crane , the main contents is each organization of crane and the metals structure patterns to really settle , and carry on the design to a structure of jib arm and counterbalance system by graphing method , including seeking the point , checking to calculate and school pit ; the second part is a design calculation that circulates the organization , including to circulate the organization to choose the type , the round presses calculation , the stability checking of the whole machine ; the third part is to choose the driving motion version of the hoisting mechanism
说明书详细的介绍了该型号起重机的总体设计及行走机构设计和计算过程，总共分为三章：第一章为起重机总体设计部分，主要内容是起重机各机构和金属结构型式的确定，并用作图法对臂架结构和平衡系统进行设计,包括了机构找点，验算及校核；第二部分是运行机构的设计计算，包括了运行机构的选型，轮压计算，整机稳定性校核；第三部分为起升机构的传动方案选型和设计计算。