Mathematical and Physical Analysis of the Shooting Techniques of High-pole Throwing Hydrangea

By using the methods of literature and mathematical analysis, the present representative technical theory of high-pole throwing Hydrangea is analyzed, this paper analyzed the technical movements of the high-pole throwing Hydrangea of technology, such as the angle, speed and height of release of the athletes, as well as the running track data of the parabolic arc top height, the range of passing circle and the place of falling of the high-pole throwing Hydrangea champion in the 12th Guangxi Student Games in 2019. The results show that: the range of the angle of release is 640≤ α ≤720; when the angle of release is 640 lower limit, the velocity of release is v0≥13.04m/s lower limit, when the ball reaches the highest point, it passes through the lower edge of the circle. When the angle of release is 720 upper limit, the velocity of release isv0≥13.17m/s, the top of the arc of the ball is 1.8m away from the top of the circle, and it passes through the lower edge of the circle when it falls; when the angle of release is 660, the velocity of release is v0≤13.70m/s upper limit and the ball passes through the upper edge of the circle when it rises to the highest point; under the three circumstances, the arc top of the ball does not exceed the circle, and the height from the ground does not exceed 10m. At the same time, it proves the scientificity and reliability of the projection technique of Hydrangea.

Practice of Fuzzy-Ball Drilling Fluid Technology in Qinping CBM Well 12-11-3H with Six Branch Holes

The 3# high rank coal in Qinshui basin frequently takes place of falling block, sloughing hole, leaking and pipe-stuck during drilling operation. The third open of 12-11-3H well in Qinping is consist of 2 main-branch and 6 sub-branch, using fuzzy-ball drilling fluid for 3 days accomplishing a footage of 4 189.49m. In order to adjust performance of drilling fluid, mix 4 fuzzy-ball drilling fluid additives SDS, SDBS, HES PAM together according to different well condition. The density of this drilling fluid is from 0.96 to 1.08g/cm3. The plastic viscosity of it is from 7 to 17mPa.s, the yield value is from 4.0 to 10.22Pa. After using this fuzzy-ball drilling fluid, the drilling rate has increase to 95%, completing the geological demand with an average drilling rate of 12.65m/h. Compared with adjacent well, the drilling rate has been raised 11.55% with no serious falling block, sloughing or leaking in whole well. However the solid control equipments still need to be strengthened for further improving drilling rate and economic benefits.