1. Introduction
During the period of “ Fifteen ” , in order to achieve 1500m deep high efficient directional drilling, meet the needs of surface & underground combine gas drainage, and solve the problem of regional gas control in super-long working face of large-scale mines in China, research on large power directional drilling technology and equipment in medium-hard coal seams was carried out. Technical advantages of compound drilling was verified and horizontal inseam directional drilling depth was further improved.
2. Treatment solution
According to the need of gas control in the ultra-long working face of Baode County Coal Mine, CCTEG Xi’an Research Institute puts forward to adopt large power directional drilling technology and equipment to carry out the ultra-long inseam directional drilling construction. According to the arrangement of the working face and the geological characteristics of the coal seam, borehole drilling design and drilling equipment are optimized. Compound directional drilling technology was used to reduce the frictional resistance in the borehole and realize the transmission of deep borehole drilling weight. Coal seam drilling progressive extension technology and the drilling trajectory control technology were used to improve the coal seam drilling rate and realize the precision drilling of deep boreholes.
3. Construction situation
Adopting ZDY12000LD drilling rig, BLY390 mud pump truck and YHD2-1000 mud pulse wireless measurement while drilling system and underground wireless MWD directional drilling technique independently developed by CCTEG Xi ’an Research Institute, an ultra-long inseam directional drilling borehole was accomplished in 81210 working face of Baode County Coal Mine. Two boreholes with more than 2000 me deep were successfully drilled in 34 days. Total drilling footage is 5204m, and 100% trajectory lies inside the coal seam. The maximum drilling depth of the No. 1 borehole is 2311m. Average daily drilling footage is more than 200m, showing significant high drilling efficiency.
4. Achieved accomplishment
Super-long directional drilling technology and large power directional drilling equipment well meet the construction needs of 2000m deep super-long inseam directional drilling. The equipment and technique effectively solve the medium-hard coal seam super-long drilling problem, improve gas extraction efficiency, shorten working face preparation period.
Compound directional drilling technology can effectively overcome the limitations of high bending strength and low transmission efficiency of drilling power in pure sliding directional drilling at the circumstance that ultra-long directional drilling trajectory is precisely controlled. At the same time, operation procedure of directional drilling is simplified, drilling power and rotation speed are increased, and drilling efficiency is effectively enhanced. The compound drilling section accounts for 65% of the total footage. Drilling efficiency is effectively improved while realizing accurate borehole trajectory control. When the borehole depth exceed 2000 meters, drill efficiency still can reach 90 meters per shift (8 hours).
ZDY12000LD large power directional drilling machine provided the feed pressure for deep hole drilling and the rotary power for compound drilling. The capacity reserve of the drilling rig system is surplus. Pressure resistance of the mud pump system is strong. Through the control of the mud pump pressure and flow rate, the compound drilling can give full play to its advantages. Data transmission of YHD2-1000(a) MWD system is stable, which fully meet needs for 2311m deep inseam borehole drilling.
Drilling process shows that the drilling equipment is stable and reliable, and the drilling technique is advanced. Large power directional drilling technology and equipment are of great significance to explore a new gas control mode in ultra-long coal mine working face.
5. FAQ
Q1: In which fields can the compound directional drilling technology be applied?
A: The utility model can be applied to directional drilling borehole over 1500m deep, surface and underground combined regional three-dimensional gas drainage, etc.
Q2: What can your company do in this area?
A: We can solve the main gas drainage problems in the process of mine exploration, construction, production and shut-down.
Q3: What advantages does your company have over other companies?
A: We have strong capacity to innovate, design and operate the whole drilling construction in horizontal directional drilling for coal seam gas drainage.
Hot Tags: horizontal directional drilling, China, manufacturers, suppliers, factory, wholesale, price list, buy, for sale,
