Zong Jian Guangzhou Machinery Co., Ltd. - Excavators inner telescopic arm (Lin Zongjian: 138-2229-3968) telescopic Applications: Telescopic generally divided into two types: sliding telescopic and inner telescopic arm, whether it is inside telescopic arm or wiper main application and a smaller turning radius construction environment. Telescopic basic principles: 1) telescopic arm with wear-resistant, high temperature tetragonal steel (Q690 or higher performance), through high-precision machining, first, Section III fully tightly fitted, by stroke cylinders promote or recycling the job done, this form of telescopic boom with greater working depth, vertical excavation, complete more complex than the two-stage plus the long arm of working conditions, can generally be designed to be more than three sections, used for digging deep vertical , pit environment more, within telescopic cylinders are divided into external and built-cylinder telescopic boom. Built-in cylinder is mainly used in excavators working conditions depth is not high, such as pre-auger drill, excavators depth of 15 meters. Caisson, excavation and other small singular cyclotron radius of only 15-30 dig depth selection of external cylinder telescopic boom, telescopic boom in the external fuel tank is often preceded by shell bucket.