There is dirt stuck in the wind flap or other rotating parts 1. Send the minor repair station in time to remove or replace the necessary parts. 3. If you use the air duct to refuel, do not add too much fuel at a time, but you must work hard.
[pdf] When using a hand held rock drill, it's important to follow the manufacturer's instructions carefully. This includes using the right drill bit for the type of rock you're working with, as well as following the recommended drilling speed and pressure.
[pdf] This manual describes elementary tools and techniques for hand drilling rock. Although hand drilling is slow work, it is a safe and simple way to prepare rocks for breaking with explosives, wedge and feather sets or expansion chemicals, or to accept anchor bolts.
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