The log grapple is a machine used by firefighters to remove large logs and tree trunks from the scene of a wildfire. It consists of an arm that attaches to the front of a fire truck, with a claw at its end which can be extended out in order for it to grasp onto logs or other obstructions. Log grapples have been used since the late 1800s, and fall under two categories: extending log grapples, and telescoping log grapples.
Extending log grapple:
- Usually, an extended arm is used to grasp onto tree trunks. The arm of the fire truck is moved into position manually. The claw latches onto a tree trunk or large limb, and hydraulic rotary rams on the fire truck that are coupled to the claw grasp and pull it into the bed of the truck.
- The extended arm was utilized by some of the earliest firefighting equipment as a way to remove obstacles from roadways that had to be kept free from obstruction in order for firefighters to travel freely through their communities during emergencies.
How does log grapple work?
The operator drives up to the obstruction, positions their vehicle as close as they can while still keeping enough clearance not to damage it, and deploys the arm; this takes one or two seconds in non-emergency situations. The arm has a mechanical claw on the end which can be opened, allowing the operator to put it into place around the obstruction. The operator then retracts the arm, pulling the obstruction away from its resting place to allow clearance for other fire fighting equipment.
The log grapple is locked in place once it is extended out of the truck; this prevents it from being retracted into its housing and accidentally injuring someone or damaging equipment. There are mechanisms inside of the housing that allow for the claw to be activated and retracted when necessary; these are sometimes manually operated but more commonly run by hydraulics or a pneumatic system.
What are the Ulility of log grapple?
- Log grapple is useful when there are trees on fire or on fire embers which are too large to be removed or moved by hand or machinery.
- It can be used to remove burned up vehicles from the roadway, or any other obstruction that would impede the progress of first responders.
- The cable can be wrapped around a tree, freeing up both hands of the operator if they need to operate another tool or piece of equipment, such as a chain saw to cut off branches above the firefighter’s head, or hose lines which should not be draped over obstructions like power lines.
- The log grapple allows for the removal of a tree that has fallen across a highway or road, which would normally be difficult to remove manually.
- It can also be used in areas where trees have fallen across power lines or underground power lines, removing these obstructions from the path of fire trucks.
- It can contribute to the overall safety of firefighters by removing obstacles that could cause them to fall over, or allowing them to dismantle exploded IEDs.
- It can be used in conjunction with a water cannon and foam hose to remove parts of a fire that have caught on fire and are burning out of control.
- The log grapple is commonly used in Australia and Canada where there is a lot of snowfall during the wintertime. Visit Alibaba Blog to know more.
