1. Set of milling and salvage drilling tools
(1) Salvage drill pipe
In order to remove the accidental drilling tools that have collapsed or stuck in the drill and stuck in the sediment intactly. After being fished out of the hole, the Xi'an Research Institute of China Coal Science and Industry Group developed φ102mm and φ127mm set milling and fishing drill pipes.
1. Structural characteristics of fishing drill pipes
φ102mm and φ127mm milling and fishing drill pipes have the characteristics of large through holes and high strength, which can meet the requirements of milling and fishing of φ73mm and φ89mm drilling tools respectively. , the structure of the salvage drill pipe is shown in Figure 7-18, and the basic parameters of the drill pipe are shown in Table 7-6.
Figure 7-18 Structural diagram of salvage drill pipe
Table 7-6 Basic parameters of salvage drill pipe
2. Precautions for use and maintenance of salvage drill pipe< /p>
1) During the process of transporting, loading, unloading and salvaging drill pipes, no bumping or throwing is allowed;
2) Before use, inspect and replace drill pipes with physical defects such as severe thread wear and bumps. ;
3) During drilling, before connecting the drill pipe, you must clean the threaded area and apply a small amount of butter;
4) When disassembling the drill pipe, first use a drill or pipe wrench to loosen it (As long as the male and female threads can rotate relative to each other), then use tools such as pipe wrench to completely remove the drill pipe manually;
5) It is strictly prohibited to mix and match new and old drill pipes;
6) After use, clean the disassembled drill pipe, apply a small amount of butter, and wear a protective cap. Store it in a dry and ventilated place and place it neatly. It is strictly prohibited to store old and new drill pipes together.
(2) Salvage bit
1. Salvage bit structure
In order to be matched with φ102mm and φ127mm set milling and salvage drill pipes respectively, China Coal Science and Technology Group Xi'an Combining the characteristics of sleeve milling and salvage technology, the research institute has developed two specifications of carbide and PDC salvage drill bits of φ107mm and φ133mm. The salvage drill bits are shown in Figure 7-19.
Figure 7-19 Two types of salvage drill bits
2. Precautions for the use and maintenance of salvage drill bits
The precautions for the use and maintenance of salvage drill bits are the same as those of directional drill bits. , please refer to Chapter 5 for details.
(3) Salvage water feeder
1. Salvage water feeder structure
The salvage water feeder is a key component that connects the mud pump and the salvage drill pipe. Its function is Send the high-pressure flushing fluid input from the mud pump into the salvage drilling tool, which is connected to the mud pump through a high-pressure hose and connected to the salvage drill pipe through a reducing joint. The appearance is shown in Figure 7-20.
Figure 7-20 Salvage water feeder
The structure is shown in Figure 7-21. The salvage water feeder consists of three parts with different functions: the mud pump connection part and the rotating part and drill pipe connecting part.
The mud pump connection part is the flushing medium input part in the salvage water sender and is connected to the mud pump. The plug and hose joint are the connecting parts of the mud pump, and they are interchangeable to meet the needs of different drilling processes.
The rotating part is mainly composed of a mandrel, bearings and various seals. It is used to separate the synchronous rotation of the water feeder and the drill pipe, so that the water feeder and the mud pump are relatively stationary to prevent the connecting hose from being entangled. Together.
The drill pipe connecting part plays the role of connecting the drill pipe and the water sender. It can be connected to various reducing joints and used with drill pipes of different specifications.
Figure 7-21 Structural diagram of the salvage water feeder
2. Precautions for the use and maintenance of the salvage water feeder
1) The salvage water feeder has been assembled before leaving the factory It is complete and has passed inspection. Users are strictly prohibited from dismantling it at will during use.
2) During the process of transporting, loading and unloading the water dispenser, no bumping or throwing is allowed to avoid damaging its parts.
3) Always check whether the sealing rings at the water supply connection are intact. If damaged, replace them in time.
4) Before use, check whether the connecting parts on both sides of the water sender are loose, and check whether the rotation of the water sender is flexible and free; clean the threaded connections of the water sender and apply a small amount of butter.
5) When using, use a pipe wrench to unscrew the drill pipe and avoid the threaded parts of the water feeder and drill pipe.
6) After use, drain the water inside the water dispenser, apply a small amount of butter on each threaded connection, and store it with a protective cap.
2. Drop drill fishing tools
The Xi'an Research Institute of China Coal Science and Industry Group has developed various types and specifications of fishing taps based on the characteristics of drilling tools for directional drilling in coal mines.
(1) Salvage male cone
1. Structure and performance
The male cone is one of the tools commonly used in underground directional drilling and salvage operations. The cone is divided into two types: right-hand thread (positive thread) and left-hand thread (reverse thread). The direction of rotation of the connecting thread and the fishing thread is the same. The right-hand thread male cone is used for the salvage operation of right-hand thread drilling tools; the left-hand thread male cone is used in conjunction with the left-hand drill pipe for the undercut salvage operation of right-hand thread drilling tools.
In order to meet the needs of directional drilling drilling tool salvage, China Coal Science and Technology Group Xi'an Research Institute has developed positive and reverse wire drill pipe tapers for fishing φ73mm and φ89mm drill pipes, as well as male tapers for fishing φ107mm drill pipes. , the positive and negative wire casing male tapers of φ127mm fishing drilling tool, the structure is shown in Figure 7-22.
The salvage male taper is forged, turned and heat treated from high-strength alloy steel. Its mechanical strength should meet the following requirements:
1) The ultimate tensile strength is not less than 932MPa;
2) The ultimate yield strength is not less than 784MPa;
3) The area shrinkage is not less than 40%;
4) The surface hardness of the fishing thread is HR60~65.
Figure 7-22 Salvage male cone
The specifications and parameters of the male cone for underground directional drilling and salvage in coal mines produced by China Coal Science and Industry Group Xi’an Research Institute are shown in Table 7-7.
Table 7-7 Relevant parameters of male cones for underground directional drilling and fishing in coal mines
2. Scope of application
Male cones are used for fishing from the inner hole of the fish top Luoyu, it is like a thread tap in machining. It taps the thread from the inner hole of Luoyu and connects the male cone with Luoyu. The male cone is suitable for fishing hollow drilling tools, and the intact cable-operated drill pipe and upper non-magnetic drill rod in the directional drilling tool are equipped with cable-operated structures inside, and the measurement-while-drilling probe pipe is installed in the outer pipe of the probe pipe. Therefore, Not suitable for male cone fishing.
3. Technical requirements for use
(1) Hardness inspection
The hardness of the salvage male taper thread must be greater than the hardness of the salvage drilling tool material, otherwise the buckle cannot be made. The hardness of the drill slip and the male cone thread can be compared on site. Any male cone with a hardness equal to or greater than the slip hardness can be used.
(2) Measure relevant data
First of all, the inner diameter of the fish top and the position of the fish top hole must be clarified, and the buckling part and related dimensions of the male taper thread can be measured based on the inner diameter of the fish top. , in turn, the dimensions of inserting the male cone into the fish top and making the buckle can be accurately calculated, which is convenient for on-site personnel to judge the working conditions of the male cone in the hole.
(3) The male cone enters the top of the fish
Drill the male cone down to 0.5~1m on the top of the fish, start the mud pump and punch the hole with clean water, rinse the top of the fish and the male cone thread For drilling cuttings on the surface, 10 to 15 minutes after water returns to the hole, start rotating the drilling tool at a low speed while maintaining circulation and slowly lower the male cone to find the top of the fish. When the male cone enters the top of the fish, the mud pump pressure will increase. At the same time, the drilling operation encountered obstruction when rotating. If only the rotation of the drill is blocked and there is no abnormality in the mud pump pressure, it means that the male cone has entered the annulus, and the drill should be lifted to try to find fish again.
(4) Making buckles
When making buckles, the pump must be stopped, feed slowly, rotate the drilling tool slowly intermittently, and record the number of turns of the gyrator. The actual buckle making is based on 6 to 8 Circle is appropriate. When the fish is not stuck, the drill can be lifted about 0.5m to observe the change in the drilling pressure; when the length of the broken drilling tool is large, there will be a pressure increase. When the broken drilling tool is short, the pressure change will not be obvious. , at this time, you can turn on the pump in short intervals and observe the changes in pump pressure. If the pump pressure is higher than before fishing, it means that the buckle has been successfully made; if the pressure does not change, it means that the buckle has failed. The drill should be drilled again to find the top of the fish, make the buckle, and fish again; if the fish is stuck, the drilling tool cannot be lifted. If necessary, other corresponding salvage measures should be taken at this time.
(5) Lifting and landing fish
If the drilling tool is not stuck, the drilling tool should be pulled out immediately. If the drilling tool is stuck, it can be cyclically combined with strong pulling, rotation or sleeve milling to salvage. During accident handling, it is strictly prohibited to reverse the rotor to prevent the male taper from slipping or the drill pipe from buckling.
(6) Other precautions
Under the action of gravity, the top of the falling fish will stick to the lower side of the hole wall. When the drill hole diameter is expanded, it may sometimes be difficult to find fish. In this case, the top of the male cone can be cut into a horseshoe shape, or a curved drill rod or a bent joint can be installed on the male cone to increase the possibility of contact between the male cone and the top of the fish.
4. Maintenance
Male cones should be stored in a dry and ventilated place to prevent rust. During transportation and storage, it should be placed horizontally. Dropping, bumping, and contact with corrosive substances are strictly prohibited.
(2) Salvage female cone
1. Structure and performance
Like the male cone, the female cone is forged, turned and processed from high-strength alloy steel. Processed by heat treatment. The mother cone is also divided into right-hand thread and left-hand thread. The right-hand thread mother cone is used for fishing with right-hand thread drill tools. The left-hand thread mother cone is used with the left-hand thread drill pipe for undercut fishing of right-hand thread drill pipe. Structure As shown in Figure 7-23. The performance requirements of the female cone are the same as the male cone.
Figure 7-23 Schematic diagram of the structure of the fishing nut cone
The positive and negative nut cones used for fishing φ73mm and φ89mm drill pipes produced by China Coal Science and Technology Group Xi’an Research Institute, specifications See Table 7-8 for parameters.
Table 7-8 Relevant parameters of the female cone for underground directional drilling and fishing in coal mines
2. Scope of application
The female cone is made from the outside of the fish top. The cone is a tool for fishing out fallen fish. It is not limited by the structure of the drilling tool. Therefore, the female cone is suitable for fishing all kinds of directional drilling tools downhole.
3. Technical requirements for use
(1) Hardness testing
The method of testing the thread hardness of the female cone is the same as that of the male cone.
(2) Measure relevant data
According to the position of the fish top and outer diameter, predict the buckle-making position of the female cone, calculate the size of the fish top inserted into the female cone, and draw a sketch. Indicates the dimensions of each part to guide salvage operations.
(3) The female cone is inserted into the top of the fish
Drill the female cone down to 0.5~1m on the top of the fish, turn on the mud pump and punch the hole with clean water, rinse the top of the fish and the female cone wire To remove the drilling cuttings on the surface, 10 to 15 minutes after water returns to the hole, slowly lower the mother cone to find the top of the fish while maintaining circulation. When the drill encounters resistance, the drill tool can be slowly rotated intermittently and the top of the fish is introduced into the drill tool until the resistance disappears. , you can continue to run the drilling tool, and when you encounter resistance when drilling again and the pump pressure rises, it proves that the top of the fish has entered the female cone, and you can stop the pump to make a buckle. If there is no obstruction in drilling and the mud pump pressure does not increase, it means that the female cone has been inserted into the annulus between the fish top and the hole wall. The drill should be lifted and the fish should be found again.
(4) Making buckles
Compared with the male cone, the contact area between the female cone and the top of the fish is larger, so greater force is required to make the buckle. The actual buckle takes 5 ~7 circles is appropriate. The method of judging whether buckle making is successful is the same as male cone fishing.
(5) Lifting and landing fish
The technical requirements for lifting and landing fish in female cone fishing are the same as those in male cone fishing.
(6) Other precautions
In order to increase the probability that the top of the fish is introduced into the female cone, a bent drill pipe or bent joint can be connected to the female cone.
4. Transportation and maintenance
The maintenance method of the female cone is the same as that of the male cone.