How to get the crawler excavator derailment 

Find an excavator and a longer crowbar, and use the working device to earn the tracks on the derailment side first. If the guide wheel derails, after draining the butter, just dig and hook it in. If it is the derailment of the final transmission side, it will be more difficult to handcuff. First earn the tracks on the derailment side to drain the butter, and use the excavator to hook out the guide wheel side first. To hook the X frame, let the chain all derail, and then install the chain on the final transmission side with an excavator first, and then install the guide wheel side, so that it is easier to install. Remember to butter after installing the chain, and tighten it.