Rotary drilling rig drill rod assembly is a combination of guide frame, drill rod, lifter ... drill rods are usually divided into 3 types: machine lock rod, friction rod, combined rod.
Friction rod is composed of seamless steel pipe and internal and external driving keys welded to it (below):
There are two types of external drive keys: six-button type and three-button type. There is no pressurized lock in the middle of the external drive key. The downward pressure is the downward friction between the gravity of each section of drill pipe and the internal and external keys during drilling. It is generally used for drilling construction in softer strata, and can be drilled into silt layers, mud, (mud) sand layers, and pebbled (stone) layers.
Each drill rod of the machine lock rod is composed of seamless steel tubes and internal and external drive keys welded to it (below):
There are two types of external drive keys: three-button type and six-button type. There are two to four pressurized locking platforms in the middle of the external drive key. When the inner drive key of the drill pipe is turned into the pressurized lock table of the outer drive key, the downward pressure generated by the pressure cylinder of the power head is directly transmitted to the drilling tool, and the mud layer, mud, (mud) can be drilled. ) Sand, pebbled, and strongly weathered rock.
The outer sections of the combined rotary drilling rod are machine lock rods, and the inner sections are friction rods.
Proper maintenance of the drill pipe can prevent and prevent premature wear of the drill pipe, and at the same time help even repair of damaged parts of the drill pipe. After the daily work, the sludge on the drill pipe should be cleaned, and the drill pipe should be thoroughly cleaned before starting maintenance work.
The following four "inaccurate" should be done during the maintenance of rotary drilling rig drill pipe
1. When drilling into sand or pebble layers, the operator must pay special attention. Do not drill too deep at one time when drilling, otherwise the hole wall will be reduced in diameter, and there will be no gap between the drill barrel wall and the hole wall, which will make the drill unable Forward or reverse rotation or lifting, causing major accidents such as stuck drilling.
2. Drill rods and rotary drilling rig bits can only be used for the drilling of pile holes, and are not allowed to be used for soil transfer, handling, or leveling at the construction site. Never immerse a drill in liquid concrete. The drilling operation can only be started when the drill bit touches the bottom of the hole.
3. According to the geological environment, a suitable drill bucket should be selected. Selecting a bucket suitable for geological requirements not only improves work efficiency, but also avoids major accidents such as stuck and buried drills in rotary drilling rigs.
4. When using the Kay (machine lock) drill pipe, please note that when the drill pipe is lifted from the pile hole, you need to pay attention to observe the situation of the outer section of the drill pipe. If the outer drill pipe is lifted out of the power head prematurely, it means that a certain drill pipe is not fully unlocked when retracted. You must follow these steps:
(1) Immediately stop the lifting operation of the main hoist to prevent the drill pipe from being opened by itself during the lifting process. The section of drill pipe that has not been unlocked may slide freely and cause a fall. The wreckage loss is very serious, and it is possible to scrap the entire drill pipe and pile hole.
(2) Slowly drop the drill pipe back into the bottom of the drill hole, reverse the drill pipe, and lift out the drill pipe after confirming that it is unlocked.
(3) During the maintenance of the rotary drilling rig, the drill pipe should be removed and inspected after the soil is poured.
(4) Open the drill pipe and thoroughly inspect and repair the drill pipe.
Three factors affecting the service life of drill pipes
1. Is the design torque of the drill pipe similar to that of the rig?
2. Whether the steel pipe material is qualified
3.Gap between layers