Theoretical study on trajectory control of gas robbing and perforation Xu, ç °çŸ³æœªå¾·æ•™ä½Content summary This paper introduces a new type of curve non-excavation pipe laying equipment trajectory controllable pneumatic piercing machine, and in the special structure and construction method 18 trajectory controllable The purpose and method of pneumatic piercing machine 0 series pneumatic piercing machine is a non-excavation pipe laying construction machine successfully developed by the underground piercing machine development group of Tongji University. It is suitable for laying pipelines with a diameter of 5,500 and a distance of 208 plus.
Its construction methods mainly include extrusion method and casing method. The pore size of extrusion method 1 is below 40 stomach. Before the construction, the relevant technical data or pipeline instrument should be used to detect the underground pipeline to prevent the existing pipelines and cables from being damaged during the construction. During construction, the working pit and the target pit shall be excavated on both sides of the road where the pipeline is laid. The length of the pit shall be 50 longer than the piercing machine 2, and the width may be suitable for personnel construction. The working pressure of the puncher is 0.6 0.7 elbow 8, and an ordinary air compressor can be used. 3 is a chassis for adjusting the initial position of the puncher, and the sight 1 and the pole 4 can accurately position the punch. The punching machine can not be corrected by itself during the perforation process, so the accuracy of the initial positioning of the punching machine is directly related to the linear precision of the pipe hole. After the positioning is completed, the punching machine is supplied with high-pressure air, and the punching machine squeezes the soil forward, and then leaves the working hole. . Dragging the pipe into the hole completes the laying task. During the entire construction process, the traffic was not interrupted and the road surface was not damaged.
In addition, pneumatic piercing machines can also be used to construct tunnels that cross railways or dams using pipe shed construction techniques. The construction process does not affect the train operation, and the construction cost can be reduced by about 40. During the construction process, the punching machine densely smashes the steel pipe through the subgrade along the predetermined contour of the tunnel, and the steel pipe is used for external support, and then the two ends are connected to each other through the steel structure. After completion, the intermediate soil is excavated and then properly processed to form a precedent for large-scale construction through the railway. Given the actual national conditions in China, it is believed that this construction method will have a very broad application prospect.
At present, the equipment for construction curve holes that are commonly used at home and abroad is directional drilling, and 2 is the simplification of directional drilling construction and its main components.
1. Drilling head 2. Sensing and launching device 3. Flexible rod 4. Clamping post device 5. Rotating device 6. Push-pull mechanism 7. Rack directional drilling is clamped by the drill head 1 flexible rod 3 The post device 4 rotates the device 5 and pushes the mechanism 6 and the frame 7. The front end of the drilling head is a bevel structure with a launching device 2, and the depth and inclination angle of the drilling head can be measured by the ground receiving device for trajectory correction. The flexible rods 3 are segmented, with each section 13 being threaded through the middle.
The flexible rod is made of special materials and has the minimum strength and deflection. The radius of curvature of the construction machinery 200113 is 412543. The device 5 clamps the flexible rod 3, which can generate a large rotating torque, and can also push and pull the drill rod through the push-pull mechanism. force. The joints of 4 and 5 complete the post, and the frame 7 plays a supporting role, and has a slide rail and a transmission device for the device 5 to drive the flexible rod to move forward. If the drilling head 1 is in a rotary plus propulsion condition driven by the devices 5 and 6, a linear advancement is made; if the devices 5 and 6 are only propelled without rotating, the drilling head will be curved. The direction in which the specific drill bit moves depends mainly on the position of the bevel of the drilling head. When the inclined surface faces upward, the drilling head will move upward. Directional drilling is a curve running in the vertical direction by means of the oncoming resistance of the soil, forming long holes in the ground. In addition, the directional drilling mud circulation system inputs the retaining wall mud into the front part of the drilling head through the burning rod, which both softens the soil and lubricates the working head, reduces friction and cools the sensor.
The directional drilling works in a static thrust plus rotation mode with a thrust of about 1. bistable head 2. sensing and launching device 3. punching machine body 4. flexible rod 5. frame 6. pressing wheel 7. clamping rotation Propulsion device 8. Compressor tube 9. Air compressor 10. Receiver. Display device lOOkN, rotating torque up to 1000kN, mD However, the structure of the directional drilling is more complicated, the recoil force is larger, and the requirements for the flexible rod are relatively high. The above 3 is the 30170 track controllable pneumatic piercing machine that we are developing for curve construction. The main body diameter is 0=70 stomach, the perforation distance is 1=3090, the radius of curvature is 7,515, and 3 is the main body of pneumatic piercing machine. Similar to the punching machine, there is an impact piston inside, which causes the punching machine to generate an advancing impact force under the action of air pressure. 1 is a conical bistable head mounted on the front end of the puncher, and the structure of the rear bevel has a symmetrical and beveled position. 2 is a sensing and transmitting device installed on the head. The ground receiver can measure the exact position and posture of the punching machine in the underground, check whether it matches the predetermined trajectory, so as to adjust the corner position of the bistable head 1, and correct the perforation. The actual running track of the machine. The simple guide frame 5 has a device 7 for rotating the burnt rod 4 and can be driven by a hydraulic motor and a pinch wheel 6. The flexible rod 4 is fixed by a specific mechanism and a puncher body, and the flexible rod is usually multi-section, each saving L2m, the inter-section is connected by a special quick connector. 8 is a pressure hose that supplies high pressure air to the piercer at a pressure of about 0.60.7. The perforator exhaust is accomplished by the gap between the pressure hose and the flexible rod. It is an explicit device that can display the corner position and depth parameters of the bistable head 1 in order to correct the track of the punching machine track 48.
The working principle of the SDH70 track controllable pneumatic piercing machine is briefly described below. The chassis 5 is adjusted so that the puncher obtains a suitable angle of incidence, the bistable head 1 is rotated to a symmetrical position, the flexible rod 4 is pressed with a suitable force by the pinch roller 6, and then the punch is supplied with air. At this time, the impact plunger in the puncher makes a reciprocating impact motion in the cylinder, driving the puncher to advance against the soil resistance. The bistable head is in a symmetrical position, the resistance formed by the extruded soil is symmetrical in the circumferential direction, and the force in the plane perpendicular to the running direction of the punch is balanced, causing the punch to move linearly. If the punching machine is to make a curve motion, the burning rod 4 can be rotated 180 by the rotating device 7 relative to the bistable head 1 to be in an asymmetrical bevel position. Since the bistable head is subjected to unbalanced resistance in a plane perpendicular to the running direction, it makes a curve motion. Through the receiver 10 and the display, the actual position of the puncher in the ground can be determined, and after comparing with the theoretical trajectory, it is determined whether the direction correction should be performed. After the length of the flexible rod enters the soil, the other flexible rod 4 that is placed over the hose 8 can be inserted and continue to advance until the punch drills the ground. After forming the original hole, the anti-pull laying can be seen from the above analysis. The SDH track controllable punching machine is used for curve construction. Compared with the directional drilling, there are two significant advantages. The punching machine advances against the impact force, and the flexible rod only bears very little. The shaft construction machine 2001 has a force and a relatively small torque, and thus the force state is greatly improved.
Due to the impact force of the punching machine, the guiding frame has a simple structure, small size and light weight.
2 bistable head structure and theoretical analysis bistable head is the most critical part of the 5070 trajectory controllable pneumatic piercing machine. The principle of curve operation is based on the unique bistable head structure, with two working states of symmetry and asymmetry, 4 and 5 It is known from the knowledge that the bistable head is a cone structure, and the back of the cone has a corner bevel, and the half angle of the cone is required to be 1=2.
The rear cylinder is embedded in the body of the puncher for rotation support.
The two have 90 sector-shaped bumps on the inclined surface to limit the two corners to 180=. There are large blades 1 and small blades 2 on both sides of the cone, both of which are arranged along the cone axis, and the cutting angles are respectively 2 and.
The bistable head has two symmetrical positions and a bevel position. The puncher impacts the plunger to produce a forward impact force 7 from the impact plunger at 3.54.58. In addition to overcoming the frictional resistance, the puncher also overcomes the forward resistance of the soil 2圮, which is related to the forward facing area of ​​the puncher and the soil quality. When the bistable head is in the symmetrical position 4, the positive pressure pressed on the bistable cone is symmetrically equal on the circumference, and the radial component 1 and the axial component 71 are also equal, so in the vertical direction The upper force is equal to zero, but at this time, because the size of the blade has a chamfer angle, 2 and 3, forward resistance will occur when advancing, so clockwise torque is generated in +PLj, P4 is perpendicular to the force component of the blade; L3, L4 The vertical distance from the force component to the center of rotation.
4, to the construction machinery 20013 Cai 1 through the 90 limit block on the inclined surface, in order to make the flexible rod rotate clockwise, but because of the action of the pressure roller 6, it can not rotate, so the financial 1 becomes a bistable head in symmetry Stable moment of position. As long as the rod is clamped, the bistable head is in a symmetrical position and the puncher runs in a straight line. If the flexible rod is driven by the rotating mechanism 7 to rotate counterclockwise 1805, since the blade is inserted into the soil, the cone does not move, so that the bistable head is in the inclined position, and the force is 5. Because the cone forms a slope, it is perpendicular to the axis. The reaction force is larger than the axis of the anti-force corpse 5 small blade is subjected to the resistance of the vertical force of the axis perpendicular to the axis, the angle between the bistable head and the axis. The heart corpse 5 pushes the puncher upwards, which causes the puncher to run in a curve. In 5 and 1, if the influence of the blade chamfer is omitted in the force of the large and small blades, the vertical force corpse 5 and the heart are the forces that make the bistable head rotate, generating a stable torque of 25 M2 torque, and the two limits of the slope Block to bear. When the flexible rod is clamped, the limit block limits the rotation of the bistable head, so the bistable head of the punch is stable when it is advanced.
The puncher can be operated in both straight and curved modes. In order to achieve the two specific conditions of the bistable head, it is very important to reasonably select the width and the chamfer of the cone angle. The design should pay full attention to the following points of the bistable head bevel angle, which is equal to the angle of the cone angle. The larger the forward resistance makes the force of the puncher curve run smaller. The shorter the cone structure, the disadvantages of operation in soft soil, and the difficulty in handling the blade arrangement. It is more appropriate to call 10 or so.
The function of the large and small blades is to stabilize the bistable head and also apply a rotating external moment to the flexible rod. The cutting angle of the blade should not be too large, too much influence the minimum radius of curvature of the flexible rod; too small, when the soil is soft, the stabilizing torque is too small to achieve stability.
In the structural design, the bistable head and the main body of the punching machine should be free to rotate, and the inclined surface should have a waterproof function to prevent the water from affecting the rotation.
The flexible rod must be burnt and have a set of torsional stiffness and strength.
4 Because the flexible rod transmits torque in both directions, the quick-connecting rod cannot be threaded. It is necessary to adopt a special quick-connecting type, and the joint should have a sealing function to prevent water ingress.
3 Sensing and launching devices are particularly noteworthy. In order to keep track of the position and attitude of the curved puncher in the ground, the sensing and launching devices must be installed in the head of the curved punching machine. Usually, there are two parts of the bistable head corner position. sensor. It mainly shows the position where the bistable head is located in order to adjust the correction, generally using a gravity device or other means.
Depth transmitter. It is mainly used to determine the actual position of the piercer head in order to compare with the predetermined trajectory, generally using an electromagnetic wave transmitter, which is received by the ground receiver.
Since the book 70 puncher is a vibration impact machine, both micro-sensing instruments are required to have a predetermined impact resistance.
The 3070 trajectory controllable pneumatic punching machine absorbs the advantages of both the 0 series pneumatic punching machine and the directional drilling machine. It combines the bistable head structure and the vibration impact to solve the problem of laying the curved pipeline in the non-excavation construction. The development of excavation technology has opened up a new world.
1 Xu Baofu. 00 series pneumatic punching machine introduction. Journal of Tongji University, 1997 2 Zhang Wei, Chen Xingqing. Non-excavation underground pipeline construction technology in the United States. Prospector 4 Gao Naixi, Zhang Xiaoyu. Pipe jacking technology. China Building Industry Press, 1984 5 Zhu Baili, Shen Zhujiang and so on. Calculate soil mechanics. Shanghai Science and Technology Press, 1990 Xu Baofu Yao Yanshilai, Lu Minwei, Department of Mechanical Engineering, Tongji University, 200092 Shanghai Ping Road Received 200010 26 Edited by Yang Xiaoguang Construction Machinery 2001
Steel Screw Machined Parts,Stainless Steel Screw Machine Parts,Custom Screw Machined Parts,Stainless Steel Screw Machined Parts
Stand Dragon Industrial Co., Ltd. , https://www.standdragontw.com