The telescopic arm of excavator is a special working device mounted on the arm of excavator, which is used to flexibly expand its operating radius and vertical deep excavation range. How does the telescopic boom excavator renter classify it?

　　一：伸缩臂挖掘机分类

　　Classification of telescopic boom excavators

　　按其结构外型可分为：外伸缩和内伸缩; 外伸缩是通过伸缩缸及滑块的作用使移动体在固定体上方使其自由伸缩。内伸缩是移动体套入固定体内，通过伸缩缸的伸缩使移动体伸出及缩回

　　According to its structure appearance, it can be divided into: outward expansion and inward expansion; outward expansion makes the mobile body free expansion above the fixed body through the action of the expansion cylinder and slider. Internal telescoping is that the mobile body is inserted into the fixed body, and the mobile body is extended and retracted by the telescoping cylinder.

　　按其工作原理可分为：顺序伸缩和同步伸缩。顺序伸缩采用多级缸或多个单级缸等方式直接用油缸推动;同步伸缩采用单缸加钢丝绳、滑轮组件实现伸缩。

　　According to its working principle, it can be divided into sequential expansion and synchronous expansion. Sequential expansion is driven by multi-stage cylinder or single-stage cylinder directly, and synchronous expansion is realized by single cylinder plus wire rope and pulley assembly.

　　二：伸缩臂挖掘机特征

　　2. Characteristic of telescopic boom excavator

　　外伸缩臂其特征主要在于：

　　The characteristics of the telescopic arm mainly lie in:

　　1、外伸缩臂由上滑动臂与下固定臂两部分构成，上滑动臂安装在下固定臂上方，通过两侧滚轮及道轨上下组成活动体，通过伸缩缸的伸缩来推动上滑动体前后自由伸缩。

　　1. External telescopic arm is composed of upper sliding arm and lower fixing arm. The upper sliding arm is installed above the lower fixing arm. The upper sliding arm is composed of movable body through two rollers and rails. The upper sliding body can be freely telescoped by telescopic cylinder.

　　2、上滑动臂内装伸缩缸，伸缩缸的缸体固定在下固定臂上，伸缩缸活塞杆固定在上滑动臂上。其主要部件有：固定体、移动体、滑块、伸缩缸等。外伸缩臂具有受力大、结构简单，能够自由调整工作半径、调整挖掘深度，易于操作，适应特定环境作业。但其行程较小，一般其行程在4米内。

　　2. The upper sliding arm is equipped with a telescopic cylinder. The cylinder block of the telescopic cylinder is fixed on the lower fixed arm, and the piston rod of the telescopic cylinder is fixed on the upper sliding arm. Its main components are: fixed body, mobile body, slider, telescopic cylinder, etc. External telescopic arm has large force, simple structure, can adjust the working radius freely, adjust the depth of excavation, easy to operate and adapt to specific environment. But its journey is small, usually within 4 meters.

　　内伸缩臂其特征主要在于：

　　The inner telescopic arm is characterized by:

　　1、 内伸缩臂是由移动体套入固定体内，通过伸缩缸的伸缩使移动体伸出及缩回，从而达到自由伸缩的目的;

　　1. The internal telescopic arm is inserted into the fixed body by a mobile body, and the mobile body extends and retracts through the expansion of the telescopic cylinder, thus achieving the purpose of free telescoping.

　　2、 其结构只有一个固定体和一个或多个移动体，节为固定体，其余的是移动体，移动体按其大小先后顺序套入固定体内，原理是二节套入一节、三节套入二节….，通过伸缩缸使其有顺序伸出或缩回;内伸缩臂其结构较复杂、生产成本较高，一般设计成两节以上，用于深坑作业的抓取与扬土。其优点是增大了作业半径以及挖掘深度。

　　2. Its structure has only one fixed body and one or more mobile bodies. The first section is fixed body, the rest are mobile body. The mobile body is inserted into the fixed body in order of its size. The principle is that two sections are inserted into one section and three sections are inserted into two sections. The inner telescopic arm has complex structure and high production cost. It is generally designed to be more than two sections for grasping and lifting soil in deep pit operation. Its advantage is to increase the working radius and excavation depth.

　　挖掘机伸缩臂应用领域：均应用于受工作半径以及深挖范围限制的特殊作业环境，可以灵活的增减其作业半径与挖掘深度范围，有效的提高工作效率。

　　Excavator telescopic boom application field: all of them are applied in special working environment limited by working radius and deep excavation range, which can flexibly increase and decrease its working radius and excavation depth range, and effectively improve work efficiency.