On Technological Innovations in Drilling Steel and Tool Enterprises
Abstract：At first，the paper explains the concept of technological innovation on the basis of theory．Further more，it point out that if a drilling steel and tool enterprise want to advance and remain invincible facing fiercely market competition，the enterprise must carry out innovations，especially technological ones. Using examples，the paper illustrates the technological innovation should rely on following two points：advanced and reliable technology as well as market demands．
Key words：innovation；drilling tool；threaded drilling rod
My country’s drill rod products only stopped in the 1980s and 1990s Stay at the level of annual consumption of more than 30,000 tons and enter the 21st century After that, the annual consumption is rising, only in 2009 H22 mm The output of cone-connected drill rods reached 100,000 tons.
Let’s analyze that in recent years, many brazing steel and drilling tool companies have The innovative project I want to carry out – hollow steel for threaded drill rods and chisel.
2.1 Main products of threaded drill rods
Hollow steel and drill rods for threaded connection drill rods. it includes for Hydraulic drill rod H28 mm, H32 mm, R32 mm, H35mln, R39 mill, R46 mm, R52 mm hollow steel, for tubular R56 mm, R60 nun, R64 mm tubular type of drill pipe drill rod Hollow steel, and threaded drill rods made of these hollow steels.
2.2 Technical Feasibility Analysis
With the continuous development of medium and deep larvae technology in recent years, efficient High-efficiency and high-power hydraulic rock drills are widely used. hydraulic rock drilling The machine was produced and applied in the 1970s A new type of rock drilling machine, which has high energy utilization rate, output power High rate, fast drilling speed, low noise, good working site conditions, environmental protection It has the advantages of less environmental pollution, high drilling efficiency and extended tool life. The matching threaded drill rod is a drill rod product with high technical content. kind. With the continuous development of medium and deep hole rock drilling technology in recent years, high The wide application of efficiency and high-power rock drills greatly improves the rock drilling efficiency. improve. This requires that the drill rod products can withstand high frequency and high power impact. impact, high torque and high fatigue resistance. drill rod for rock drilling It is a slender rod body, its service condition is to bear in the corrosive medium Loaded by multi-stretch tension and compression, multi-stretch bending and multi-stretch torsion, so Excellent material properties are required. After calculation, the impact of the hydraulic rock drill Under the load condition of 340J work, the threaded drill rod breaks The instantaneous actual force is 823 MPa. Therefore, the drill rod must be selected to resist The tensile strength is 1373 MPa and the yield strength is above 1275 MPa of ultra-high-strength steel.
Production process of threaded chisel
(1) Foreign (take Sweden Sandvik Company as an example) thread drill rod production process
The material is 20CrNi3Mo, FF710 and other steel types, and the process flow Chengwei:
Scrap steel selection-smelting-LF refining-VD vacuum treatment Rationale, pouring large steel ingot, heating, billet cutting, peeling, mechanical drilling Hole-core loading-heating-rolled material-core pulling-hollow steel-forging Manufacturing-mechanical processing-carburizing-air quenching (forced air cooling)-low temperature Tempering—inspection—straightening—shot blasting—rust prevention—packaging—storage. Its processing characteristics are: the material is carburized with low carbon medium alloy steel. After carburizing, quenching and tempering, good strength and toughness can be obtained Issue high fatigue life and high surface hardness meet the requirements of the drill rod conditions of service. Advanced steelmaking and steel rolling process make the steel pure High density and large compression ratio can realize the purification, homogenization and crystallization of steel Granular refinement provides high-quality materials for brazing. Product quality is stable fixed, high service life, medium hard rock, uniaxial compressive strength The drilling speed is 100 MPa, and the rock drilling footage is about 4,000 meters per branch, which is an international Recognized as the best threaded chisel production process. But its process route long. The cost of raw materials and production is high, and the rolling process and size Precision, heat treatment process and equipment requirements are high, precise control is difficult Large, the domestic has not yet fully mastered its technology.
(2) Production process and characteristics of domestic threaded drill rod
The domestic heavy-duty rock drilling rod material is 20CrNi3Mo, FF710 and other steel grades. The process flow is divided into the following categories:
Process one (imitation of foreign technology):
Scrap steel selection-smelting-LF refining-VD vacuum treatment Rationale, pouring large steel ingot, heating, billet cutting, peeling, mechanical drilling
Hole-core loading-heating-rolled material-core pulling-hollow steel-forging Manufacturing-mechanical processing-carburizing-air quenching (forced air cooling)-low temperature Tempering—inspection—straightening—shot blasting—rust prevention—packaging—storage.
Round steel—peeling—heating—piercing—hot rolling and reducing (or hot rolling) drawing)-hollow steel-forging-machining-carburizing-empty Quenching, tempering, inspection, straightening, shot blasting, rust prevention, packaging storage. Its technological characteristics are: short production process and low cost.
Excellent products produced by drilling method or hot piercing-hot rolling (drawing) method Quality hollow steel – forging – machining – normalizing – quenching -Tempering—inspection—straightening—shot blasting—rust prevention—packaging—storage. This method can be used to produce impact energy is not too high, the impact frequency is not too high High hydraulic rock drilling sites (such as COPl038, Mercury-300 hydraulic Rock drill).
The threaded drill rod is made of low-carbon high-strength alloy steel after carburizing and Quenching and tempering + shot peening + anti-corrosion treatment is currently the best thread brazing Rod brazing process. However, the uniformity of the carburizing furnace temperature, the surface carburizing layer Depth control, control of the bending degree of the rod body during quenching, thread The dimensional accuracy and roughness of the machined surface are the factors that determine the threaded brazing Discussion on Technological Innovation of Brazing Steel and Drilling Tool Enterprises A key factor in rod quality. Especially the surface carburized layer requires no block Shaped and reticular carbides, no defects such as internal oxidation, the surface hardness should be It is difficult to achieve a gentle gradient in the process.
After the low-carbon high-strength alloy steel is carburized, quenched and tempered, Although the surface hardness, wear resistance and fatigue of the threaded drill rod are increased Strength, but also increases the notch sensitivity of the surface of the threaded drill rod sex. This process does not fully meet the requirements of the threaded drill rod in the rock drilling process. middle. Produced by the high-frequency impact between the coupling sleeve and the drill rod thread High heat resistance to softening. Therefore, threaded drill rods still have issues to be solved. Do in-depth research.
In summary. The manufacturing process of threaded drill rod is more complicated and difficult Larger, currently the threaded drill rods produced in my country are at the advanced level in the world In comparison, there is still a big gap.
2.3 Market Analysis
(1) Domestic market
China’s national economy has experienced rapid development for many years. GDP continuous Keep at around 8%, infrastructure such as roads, railways, and water conservancy projects The scale of construction continues to expand; the domestic industry’s The demand for gold and non-ferrous metal minerals continues to grow, leading the mining industry The mining industry expanded rapidly. These infrastructure projects and mining are inseparable from The mining of drill rods for excavation has also led to a rapid increase in the consumption of drill rods.
The threaded drill rod is a supporting tool for hydraulic rock drilling rigs. along with my country’s large-scale infrastructure projects have started one after another, and mechanized construction operations The degree will be further increased. The use of large drilling rigs will also be relatively Substantial improvement. Demand for threaded drill rods will also increase add. According to the statistics of China Brazing Steel and Drilling Tools Association in 2012, the national The output value of drilling tools is 6 billion yuan, of which the output value of threaded drill rods is about Accounted for 6%, or 360 million yuan. The production of threaded drill rods for hydraulic rock drilling rigs marks a The level of drill rod manufacturing in a country, the current domestic production of threaded drill rod The manufacturers are: Shougang Guiyang Special Steel Co., Ltd., Guiyang Huifeng Zhongyi Drilling Tools Co., Ltd., Liaoning Lianhuashan Rock Drilling Tools Co., Ltd., Shandong Sanshan Group Wuyue Brazing Steel Drilling Tools Co., Ltd.,Hubei Jiayu Brazing Tools Co., Ltd., Henan Jiaozuo King Kong Drilling tools Co., Ltd., etc. But our country is in the thread drill rod Production technology has not yet fully passed. Half of the domestic threaded drill rod depends on foreign imports, and some people estimate that its annual demand is about
2 billion yuan, and it is increasing year by year.
(2) International market
It is still difficult to determine the market share of brazing tools in the international market The main suppliers are Sandvik and Atlas in Sweden, Boartlongyear in the United States, Furukawa in Japan, etc. these international The technology of famous drilling tool companies guides the development of drilling tools in the world. The threaded chisel products produced are of good quality and high price, although the price It is about 1.5-3 times the price of domestic drill rod products, but the product is still about Accounting for 80% of the international market. my country’s threaded drill rod market is also basically Basically owned by these companies.
Whether it is the production and processing of the enterprise or the on-site rock drilling of the operator, It is necessary to strengthen the protection of the edges and corners of the drill rod to avoid damage to the edges and corners, so as to Ensure the normal service life of the chisel. Early internal fatigue fracture loss effect. The main reason is the problem of raw materials, enterprises should strengthen For the liner, the combination of the liner and the substrate, and the purity of the steel control. Ensure intrinsic quality.
Through the above comparative analysis, Shougang Guigang GⅢ tapered drill in The hollow steel rolling process and equipment have undergone a series of improvements and After optimization, the inner quality of the hollow steel is further improved, and at the same time Brazing is also continuously optimized, and product quality is more stable Certainly. Make it in the leading position in the domestic products of the same grade. At the same time, recent market feedback: $82 rock drilling with high power and high efficiency machine. A number of user units are equipped with mainstream products on the market It reflects that only “GⅢ brazing of Shougang Guigang” has the best effect. and Compared with other brazing enterprises, Shougang Guigang has its unique state-owned enterprise advantages Potential. Technology research and development, product quality improvement and transformation of tapered brazing development. Great investment. Continue to lead the development of the domestic brazing tool industry exhibition.