Therefore, the upper level controller and lower level conveyor and associated kits were dismantled, and a bracket for concave guide and flexible chain was installed.

为此，对该机组进行了改造：①拆除烟支上位控制装置和烟支下位传送装置及其组件；②设计加工并安装凹形导板和柔性搭链的支架。

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Thomas Harrah of Seth performed at least 228 pre-shift, on-shift and conveyor belt safety examinations at Upper Big Branch over a nearly two-year period from January 2008 to August 2009, according to state records obtained under the Freedom of Information Act.

FORBES: New Evidence of Deceit and Deception in Mine Disaster that Killed 29