GXW- 1000 rotary drilling rig is a kind of drilling rig used for pile hole construction. It is mainly used for drilling pile holes in urban high-rise buildings, underground engineering, hydropower, transportation, ports, national defense and other basic projects. The drilling rig does not need circulating fluid construction, which reduces environmental pollution and greatly reduces the engineering cost. In addition, the equipment has simple structure and operation process, reliable operation and low production cost. It is one of the most economical and effective drilling rigs widely used in urban foundation pile construction at present. Its main features are as follows:
1) uses a drill bucket to drill holes, and there is no circulating liquid, and the drilling slag is hoisted out of the hole with ropes, thus avoiding mud pollution and mud treatment.
2) The drill pipe adopts plug-in connection structure, which is convenient for disassembly.
3) The hinged elevator is adopted, which overcomes the operation of climbing the tower when loading and unloading drill pipes and is beneficial to safe and civilized production.
4) Adopt hydraulic walking mechanism, which is flexible in site movement and convenient and accurate in hole alignment.
5) The drilling rig adopts mechanical transmission and electro-hydraulic control, with a high degree of mechanization.
(II) Main technical performance of drilling rig
See table13 for the main technical performance of GXW- 1000 drilling rig.
Table1-13gxw-1000 Main technical performance of drilling rig
(3) Composition of drilling rig
The composition of the drilling rig is shown in figure 1-52. The drilling rig consists of base, frame, traveling mechanism, tower, power head, oil pump device, hydraulic system, tower lifting cylinder and orifice device.
The base and the carriage are welded, and the cylinder can move relatively. The stroke of the cylinder is 1250 mm, and three hoists, towers, oil pump devices, walking mechanisms and control systems are all installed on the carriage.
The tower is welded with seamless steel pipe, and the power head is welded with movable slide rail. The power head slides up and down on the slide rail of the tower. Two sets of crown blocks are installed on the tower: one set is used to lift the power head so that the power head can move up and down smoothly along the slide rail; One set is used for auxiliary hoist hoisting, which can be used for loading and unloading drill pipes, hoisting reinforcing cages and pouring concrete.
The walking mechanism is also a welded structure, and the bent beam part is matched with the slide rail of the carriage. When the drilling rig walks, it bears the quality of the drilling rig, which makes the drilling rig rotate along the arc of the curved beam, thus changing the direction of the drilling rig when it moves.
The power head is mechanically driven. The motor drives the worm gear reducer through the belt, and then decelerates through the first gear reducer to drive the drill pipe to rotate, thus realizing drilling.
There are three winches, namely rotary bit winch, power head hoisting winch and auxiliary winch. The hoist of the rotary drilling rig is used for lifting the rotary drilling rig to realize slag discharge; The power head hoist is used for lifting and decompression drilling of the power head; The auxiliary lifting mechanism is used for lifting the reinforcing cage, pouring concrete and loading and unloading drill pipes.
Figure 1-52 Overall Structure Diagram of Rotary Drilling Rig
1 base; 2- transportation; 3- Walking mechanism; 4- tower; 5— Power head; 6, 7- pulley; 8— Oil pump device; 9 10- hoist; 1 1- hydraulic system; 12- tower lifting cylinder; 13 orifice plate device
(4) Hydraulic system
The hydraulic system of the drilling rig is shown in figure 1-53. It consists of an oil tank, a gear oil pump, a pressure gauge, a multi-way reversing valve group, a one-way throttle valve, a two-way hydraulic lock, a longitudinal moving oil cylinder, a front and rear swinging oil cylinder, a front and rear leg oil cylinder, a tower lifting oil cylinder and the like.
The hydraulic system has two functions: one is to complete the hydraulic walking movement of the drilling rig and align the hole position. The hydraulic walking mechanism consists of front leg cylinder, rear leg cylinder, longitudinal moving cylinder, front swinging cylinder and rear swinging cylinder. Its action is controlled by multi-way reversing valve group. The function of one-way throttle valve is to make the action of leg cylinder basically consistent or regular (the front leg starts first and the rear leg falls first). The second is to take off and land the tower and keep it stable in a certain state. The action of the lifting cylinder is controlled by the reversing valve, and the function of the bidirectional hydraulic lock is to realize the bidirectional locking of the lifting cylinder, thus making the tower stable in a certain state.
Figure 1-53 GXW- 1000 Hydraulic System Diagram of Drilling Rig
1- oil tank; 2- filter; 3rd gear oil pump; 4- pressure gauge; 5— Move the oil cylinder vertically; 6— Rear rotary cylinder; 7— Front swing cylinder; 8— Front leg cylinder; 9— Rear leg oil cylinder; 10- one-way throttle valve; 1 1- tower lifting cylinder; 12- two-way hydraulic lock; 13- Multi-way reversing valve
(5) Drilling tool structure
The drill of GXW- 1000 rotary drilling rig has a plug-in drill pipe, a hinged elevator with latch locking spring reset and a semi-closed rotary drilling bit (drill bucket). The drilling tool structure is shown in Figure 1-54. It consists of a pilot bit, a rotary bit, a drill pipe, a short drill pipe, a hinge lifter, a movable hook and the like. The rotary drill is not only a tool for cutting and crushing, but also a container for temporarily storing soil, and its structure is semi-closed. The drill pipe adopts plug-in connection structure, which is convenient and quick to assemble and disassemble. Hinged elevators can be used to avoid climbing the tower when loading and unloading drill pipes.
(6) Use and operation of drilling rig
According to the hole diameter and hole depth required by engineering construction, the matching of drilling tools is determined: for drilling holes with a diameter greater than 800mm, 152mm drill pipe; For drilling holes less than 800 mm in diameter, use? 1 14 mm drill pipe. When drilling, the first drill pipe is a short drill pipe with a length of 2m. Connect the short drill pipe with the hinge lifter on the power head, then hang the movable hook on the drill pipe, and hang the rotary drill bit into the hole to connect with the drill pipe.
Figure 1-54 Structure Diagram of Rotary Drilling Tool
1- pilot bit; 2- rotary drill bit; 3— Drill pipe; 4— Short drill pipe; 5— Hinge puller; 6-Movable hook
1. Connecting and disassembling drill pipes
Operate the power head lowering button to lower the power head to an appropriate height, pull out the lock cap connected with the lock pin on the hinge lifter, and rotate it for a certain angle to pull out the lock pin from the pin hole. At this time, the extractor can rotate around the pin shaft. Pull the elevator to an appropriate position corresponding to the upper joint of the drill pipe hoisted by the auxiliary crane. After checking whether there is dirt and burr on the drill pipe joint, you can insert the upper joint of the drill pipe into the hexagonal hole in the elevator, install the connecting pin shaft and the cotter pin to prevent it from falling off. Reset the lock cap and lift the power head to the vertical state of the drill pipe. The reset of the locking pin indicates that the joint on the drill pipe has been connected. Then align the lower joint of the drill pipe with the upper joint of the drill pipe clamped on the orifice device. If the position is not suitable, the power head can be slightly moved, and once aligned, the power head will be slowly lowered. After the joint is in place, install the connecting pin shaft, install the cotter pin to prevent it from falling off, and lock the lock nut with a hook wrench. Repeat the above actions to connect the next drill pipe. Disassembly of drill pipes shall be carried out in the reverse order of connecting drill pipes.
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When drilling, the first drill pipe is 2m long, connect the short drill pipe with the hinge detacher on the power head, then hang the movable hook on the drill pipe, and hang the rotary drill bit into the hole to connect with the short drill pipe. Lift the power head properly, let the pin on the pilot bit leave the bottom of the hole, take the rotary bit off the movable hook and fall freely until the bit is combined with the pin. Inching the power head to make the knob pin in place, and then drilling can be carried out after confirmation. When drilling, the drilling footage should be slow, and the power head should be lowered slowly. When the drilling footage is about 500mm, the drill bit barrel will be filled with drilling slag. Then stop drilling, make the power head inching reversely, make the drill bit separate from the drill pipe, then operate the drill bit to lift the winch, and make the movable hook descend to the bottom of the hole, and observe whether the hook is in place by lowering the wire rope. When drilling deep holes, it is not easy to determine whether the hook is in place. You can mark the wire rope and stop the wire rope from descending immediately after it is confirmed in place (too many descending wire ropes are easy to entangle the wire rope, which makes it difficult to lift the drill). Then lift the hook to make the drill bit rise slowly. Then control the lifting speed appropriately according to the stratum conditions. When lifting into the hole, open the locating hook, continue to lift to a suitable position, quickly push the hole former under the drill bit, and cover it with the hole former baffle. After that, put the wire rope for opening and closing the drill bit on the lifting lug and fasten it with the pin shaft, then lower the drill bit and discharge the drilling slag into the orifice device. After slag discharge, lift the drill bit, remove the hoist wire rope, and continue to lower the drill bit to the orifice to confirm whether the positioning hook is in place; Continue to lower the drill bit, make the movable hook reach the orifice, open the hook, and the drill bit will freely fall to the bottom of the hole, that is, complete a drilling cycle. If it is repeated, it is normal drilling. It should be noted that in the process of lifting the rotary drill bit from the bottom of the hole to the orifice, discharging slag and lowering the drill bit to the bottom of the hole, the pilot drill bit and the drill pipe are stationary.
When drilling, pressure drilling or decompression drilling can be selected according to different formations.
Pressurized drilling is usually used for shallow holes. Pressurized drilling is to gently lift the rotary bit hoisting winch, and the wire rope pressurizes the drill pipe through the crown block on the power head. The magnitude of pressurization and drilling speed are related to formation conditions.
Decompression drilling is usually used. Decompression drilling is to lift a part of drilling tools and power head through the power head lifting winch according to the formation situation and footage speed, so that the quality of drilling tools and power head will not be completely added to the bit, and the purpose of decompression drilling is realized.