1.Introduction of horizontal directional drilling machine
Large-scale horizontal directional drilling rig is an important equipment for underground pipe network construction of oil, natural gas, water supply and other fields. It has the advantages of intelligence, safety, environmental protection, energy conservation, fast construction speed, low construction cost, and no impact on traffic, etc. It has been listed as an environment-friendly technology for the 2nd century by the United Nations conference on environment and development.Large horizontal directional drilling is used in petroleum, natural gas, water supply and drainage, electricity, coal water slurry and other large underground pipeline laying an ideal equipment, is energy conservation and environmental protection, high efficiency of trenchless construction equipment, the technology in the first place in the United States, Europe and other developed countries and area rise and development, domestic rig design and manufacturing level of large difference in comparison with foreign drill.
With the rapid development of China’s major national projects such as west-to-east gas transmission, south-to-north water diversion, china-myanmar oil and gas pipeline and china-russia oil and gas transmission pipeline at the beginning of this century, the production and sales of large horizontal directional drilling RIGS have experienced an explosive growth stage. Therefore, the past decade can also be called the “golden decade” of China’s trenchless equipment.
2.The difference with foreign horizontal directional drilling machine
Foreign companies that produce large horizontal directional drilling RIGS mainly include Auger company of the United States, Vermeer company, German PRIME company, TT company and herrick company.
Most of the foreign products have automatic drilling pipe access device, fast anchoring positioning device, anti-electric shock alarm and other automatic and safety protection system.Although the domestic horizontal directional drilling machine started late, its development speed is extremely fast due to the promotion of a large number of construction projects. China’s national conditions are different from those of foreign countries, resulting in the difference in the use demand and current situation of drilling machines with foreign countries, mainly in the following aspects.
1)Chassis type of horizontal directional drilling machine
China is a country with a vast territory and varied geological conditions. Large-tonnage drilling RIGS are mainly constructed in the field. Limited by the construction site, domestic drilling RIGS often use crawler chassis by themselves, with low requirements for roads and strong passing ability.
Foreign drilling RIGS benefit from good supporting conditions of basic equipment. The chassis is dominated by the trailer type vehicle chassis, which has the advantages of convenient and quick transfer in the case of convenient transportation.
2)Drilling frame structure of horizontal directional drilling machine
Because of the adoption of caterpillar chassis, the engine is generally arranged on the side of the width of the whole machine, which limits the width direction of the drill stand. Although the rear engine layout can be used to increase the width of the drill stand, the rear engine layout often causes the disadvantage of small approach Angle or departure Angle of walking.In order to overcome the shortcomings of the crawler chassis, the rocker arm structure and the slip of the drill frame should be adopted to adjust the construction man-soil Angle.
3.Major component analysis of horizontal directional drilling machine
1)Power head with booster structure of horizontal directional drilling machine
The drill with the function of increasing force can ensure the smooth construction and reduce the construction risk when the drag resistance is large.Catered to the domestic users “spend small money, do big things” idea.
2)Vise of horizontal directional drilling machine
Reliable clamping mechanism is the foundation of construction of directional drilling rig. Horizontal directional drilling technology comes from oil drilling. However, as the construction condition of horizontal directional drilling rig is greatly different from that of oil drilling rig, the torque of horizontal directional drilling rig is large, and problems such as rod slippage are very likely to occur.At present, three-cylinder clamping vise is widely used in large drilling RIGS. By increasing the Angle and contact area of the drill pipe, the clamping stress of the drill pipe can be reduced and the torque of the shackle can be improved.In addition, in the long distance construction, the casing is generally required. In order to adapt to the casing construction method, the vise of the drill is often designed with a fully floating type.
3)Power of horizontal directional drilling machine
The power of large – scale drilling rig is larger.The overall cost of dual engine configuration is slightly lower. When guiding operation or small power output, one engine can be used to work, save energy, reduce construction cost, and more importantly, construction safety. Even if an engine fails, construction operation can still be carried out.
4) Hydraulic system of horizontal directional drilling machine
In trenchless construction, there are generally three stages: pilot hole, reaming hole and drag pipe. In these three stages, rotary torque and push and pull force have different requirements for engine power output.In the stage of reaming construction, the power demand of rotation is large and that of push and pull is small.But in the pipeline backhaul stage, the push and pull power output demand is big.
According to the construction requirements, the rotary system is generally applied with energy-saving closed hydraulic system, so as to achieve the goal of energy saving. Therefore, in large drilling RIGS, the rotary system is generally applied with closed system.At the same time, in order to improve the efficiency of the hydraulic system, pumps, motors and other high efficiency plunger motor as energy conversion and execution components.
5)Electric System of horizontal directional drilling machine
With the progress of modern electronic technology, PLC controller with reliable performance, stable quality, strong logical intelligence characteristics, has been widely promoted and applied.At present, domestic horizontal directional drilling machines with PLC controllers are generally equipped with monitors and have the following functions:
5.1Main construction parameters digital display function of horizontal directional drilling machine
Drilling rig construction parameters (torque, rotation speed, push and pull, push and pull speed, mud pressure, mud flow) automatically display.
5.2Intelligent control function of horizontal directional drilling machine
b)The automatic application of energy saving control, the drilling machine applies the automatic idle system, when the drilling machine has no load output, can automatically enter the idle state, save fuel.
c)Limit power control function: according to the construction load, the equipment adopts limit power control for the engine to prevent engine overload and extend the service life of the engine.
d)The use limit of the output torque and the maximum push and pull force of the equipment can be conveniently preset by applying the intelligent control system.
e)Vise clamping force control, the application of controller, easy to achieve the control function of the drilling rig clamping drill pipe force, but also can set up a protection program, such as in the vise clamping drill pipe, automatically prohibit the power head moving back and forth, to prevent damage to the equipment by mistake operation.
f)Efficient construction process.The intelligent control system can realize the automatic and rapid construction of the drill under constant torque, constant speed, constant push and pull or constant push and pull speed, with the characteristics of instantaneous response speed and construction efficiency.
6)Safety protection of horizontal directional drilling machine
Construction safety, in the final analysis, is the safety of the lives of construction personnel and equipment safety.To ensure the long-term reliable work of drilling RIGS is the top priority in the design and manufacturing of large horizontal directional drilling RIGS. The safety of drilling RIGS generally has the following functions:
(1) safety emergency stop device, can stop the engine in case of emergency, according to the standard requirements, emergency stop device is generally arranged in the cab, power head, truck crane, amplitude change, vise and walking control box.In addition, in some unsafe areas, there is the possibility of someone entering by mistake, which will lead to a major construction accident, multiple protection devices must be set up.
(2) logic interlocking device, such as when the power head moves to the end of the drill stand or when the power head moves to the position of the drill stand bracket, the control system of the equipment can automatically slow down, stop and other actions, and give warning information to ensure the safety of personnel and equipment.
(3) overload safety protection device.Due to the complexity of construction geology, overload may occur during the construction. In case of overload, it is easy to cause the failure of sticking and breaking of drill pipe, and even cause more serious construction losses.
(4) limit position protection, mainly the limit position protection of the front and rear positions of the power head, to prevent the power head from touching the vise or the power head from coming out of the drill frame.
7)Ergonomic research and application of horizontal directional drilling machine
The construction of large drilling RIGS usually involves large diameter and long distance engineering construction, which usually requires a long construction period and a comfortable operating environment to improve the operating comfort of operators.
8)Components’ high cost performance of of horizontal directional drilling machine
Not only Chinese users, but also global users pay great attention to the cost performance of the product. On the basis of satisfying the product performance, reliability and good maintenance performance, the value engineering analysis method of the drilling rig is carried out to remove the redundant function of the product and reduce the manufacturing cost of the equipment.
4.Conclusion and prediction of horizontal directional drilling machine
As a kind of trenchless construction machinery, horizontal directional drilling machine also abided by the development trend of general construction machinery. From the development direction and development of existing general construction machinery, it can be predicted that the development trend of horizontal directional drilling machine is as follows:
(1) high integration of guidance technology and host control technology
The technology is divided into two steps: the first step is the integration of the pilot and the vehicle controller, and the information of the probe is displayed on the user’s monitor.
The second step is to realize the vehicle controller to realize the control of guided construction. The drilling curve is input into the display of the drilling rig, and the equipment will automatically complete the actual engineering construction along the input curve, or monitor the deviation between the drilling trajectory and the predetermined trajectory in real time, and remind the operator to correct o
(2) sound safety and protection functions
The vehicle-mounted safety protection system will achieve a breakthrough by upgrading the traditional alarm after electric shock to pre-alarm, that is, the system will automatically alarm and shut down when approaching the high-voltage cable. This technology can significantly improve the construction safety.
(3) power source of energy conservation and emission reduction
Power system USES to meet higher standards of efi engine, due to the efi engine has a large range of output power and variable power output characteristics, especially for the high power engine of directional drilling, light or load hours, energy-saving significantly, will spread in directional drilling, the application and reduce fuel consumption and reduce the pollution of the environment o
(4) self-assembly transportation technology
Due to the fact that the self-weight of drilling RIGS exceeds the highway transportation limits prescribed by the traffic law, the convenient disassembly and transportation technology and even the self-disassembly and assembly technology can be popularized and applied, making the transfer of drilling RIGS more convenient.
(5) improvement of supporting capacity of drilling RIGS
With the improvement of the domestic basic steel level, the steel pipe with higher strength will be manufactured and put into use, and the drill pipe meeting the demand of the super-large tonnage drilling machine will be manufactured and promoted.
The airborne large-flow mud pump technology has achieved a breakthrough and gained popularity. At present, the large-tonnage drilling RIGS are mainly independent mud pumps with high price, while the maximum size of mature airborne mud pumps is 600L.The airborne mud pump technology USES the main engine power, saves the engine procurement cost, and can greatly reduce the procurement cost after optimization.
(6) big torque drilling machine achieves breakthrough
Since the power output of the bit is proportional to the torque of the power head, that is, P T·n
Therefore, under the condition of constant rotation speed, if the construction efficiency is to be greatly improved, the output torque of the drilling rig must be improved.At present, the construction limitation of large tonnage horizontal directional drilling rig mainly lies in the limitation of drill pipe torque during construction. Once the drill pipe with large torque is applied, the torque of drilling rig will also be improved, thus greatly improving the construction efficiency.
(7) application of iot technology in horizontal directional drilling rig
The effective transmission and management of construction data are carried out by using vehicle-mounted GPS, and the remote online fault diagnosis is simply realized by using the Internet of things system.Combined with guidance technology, the system can automatically generate and store the track map of the construction route after the completion of the drilling rig.Various construction parameters can also be stored and analyzed, and the data obtained can provide effective reference for the next construction under the same geological conditions.
(8) research on a new type of large torque shackle device
If the manufacturing technology of drill pipe achieves a breakthrough, with the increase of the output torque of the drill pipe, it is necessary to effectively prevent the drill pipe from slipping during the shackle during the construction, and a new vise structure is needed. With the help of this mechanism, the damage of the drill pipe caused by the jaw can be reduced, and the effective clamping of the drill pipe can be realized.
(9) promotion of new construction methods
The research on the new construction method of horizontal directional drilling machine is underway. The implementation of the new construction method can accelerate the construction speed. For example, the push pipe has been recognized by the majority of users.In addition, the directional pipe pushing method, which combines the horizontal directional drilling machine with the pipe jacking machine, overcomes the disadvantage of low head power of the pipe jacking machine.The mud treatment after construction is paid more and more attention by the environmental protection department and party a. How to use the environment-friendly and pollution-free formula and the equipment for mud post-treatment will also be promoted.
(10) expand new application fields
At present, horizontal directional drilling RIGS are not only used in trenchless projects, but also in geothermal resource development, environmental management, slope management, shale gas, coal bed methane and other energy exploitation.
The success of horizontal directional drilling rig construction can not be achieved without reliable equipment, suitable mud and construction method, and excellent guiding curve. Only when the three coordinate with each other and form a unified whole, can the advantages of equipment be given full play and the construction tasks be completed timely, effectively and reliably.
