深井救援的技术特点与难点---
Technical characteristics and difficulties of deep well rescue---
常见井的类型有：
The types of common wells are as follows:
（一）水井
（1） Well
水井是过去人们重要的生活水源之一，直径一般为0.7-2米，深度一般为数米到20-30米，施工时工人可直接下入井筒内挖掘土石。这种井由于深度的原因只适于开采浅层地下水。此类水井由于年代久远和挖掘方法的局限性极易发生水井壁坍塌等次生灾害,给救援工作带来困难。
Well is one of the important living water sources for people in the past, with a diameter of 0.7-2 meters and a depth of several meters to 20-30 meters. During construction, workers can go directly into the well to excavate earth rock. This kind of well is only suitable for exploiting shallow groundwater because of its depth. Due to the long history and the limitation of excavation methods, such wells are prone to secondary disasters as well wall collapse, which brings difficulties to the rescue work.
（二）机井
（2） Motor well
在我国农村有很多的机井，这些机井一般都有几十米深，最深可达上百米，村民们打这么深的机井，主要是为了开采深部地下水，用来抽取地下水灌溉农田。但是这些机井的井口大多很小，一般为几厘米到几十厘米，平时无人看管，大多裸露在地面或者只用简易遮挡物遮盖。由于农村地区村民普遍安全意识淡薄，消防站距离较远，救援力量达到时间较长，这些无人看管的机井往往成为置小孩于死地的深渊。
In China's rural areas, there are many motor wells, which are generally tens of meters deep, up to hundreds of meters deep. The main purpose of the villagers is to extract deep groundwater to irrigate farmland. But the wellhead of these wells are mostly very small, usually a few centimeters to dozens of centimeters, usually unattended, mostly exposed on the ground or covered with simple shelter. Because the villagers in rural areas generally have a weak sense of safety, the fire station is far away, and the rescue force has reached for a long time, these unattended motor wells often become the abyss of killing children.