УКД 622.24

RESULTS OF LABORATORY STUDIES OF DYNAMICS DRILLING TOOLS

Автор: Huzyna L. Habdrahymov M.

Translation: Porotnikov Vladimir, student of DonNTU.

Источник:"Oil-gaz bysness".

In the oil industry, engineering and technology is constantly improving drilling operations, are increasingly well built with large waste from the vertical. Thus the basic problem is reducing the high coefficient of friction during rotation of the drill string. The methods used to reduce friction normally associated with a change in the type of drilling mud or drilling fluid, and mechanical methods are used. One of these is the use of mechanical naddolotnyh vibrousiliteley, which are based on polichastotnye pendulums. In this regard, current studies are related to determining the optimal frequency range of naddolotnyh vibrousiliteley.

Previous studies associated with the dynamics of the drilling tool. The fundamentals of studies of mechanical and abrasive properties of rocks were carried out by LA Schreiner and his student N. Pavlova, A. Spivak, B. Baydyukom etc. Critical issues in the theory of rock drilling have been solved in VS Vladislavlev, RM Eygelesa, Vladimir Simonov, BA Zhlobin, F. Resurrection, etc. Since the early 1960s. under the supervision of Professor M. R. Mavlyutova conducted research on the destruction of rocks during dynamic indentation. The study of mechanical, abrasive properties of rocks and their destruction, as well as improving the design of the leading groups engaged in bits VNIIBT institutions, MINHiGP, BashNIPIneft, UGNTU led by scientists VN Vinogradov, NA Zhidovtsevym, NF Kagarmanovym, A . N. Popov and others Assessing the impact of plasticity and the differential pressure of rock in the investigation of stability, obvaloobrazovany, Thermoviscoelasticity was carried out researchers AH Mirzadzhanzade, MK Seyed-Reza, N. Pavlova, T. Faradzhevym, EG Leonov and others. Dynamics of the drilling tool is theoretically and experimentally studied by MR Mavlyutova, RH Sannikov, BZ Sultanov, MS Gabdrahimova, GA Kulyabina etc. Experimental studies of FF Resurrection, MR Mavlyutova, AI Spivak, AN Popov revealed a number of patterns and factors influencing the destruction of rocks. However, there is still no consensus about the required frequency range for naddolotnyh mechanisms. In this regard, the department NPMO OF UGNTU conducted pilot studies to determine the optimal parameters hydropercussion mechanisms and models of their work items on a laboratory bench. In determining the optimal frequency range of mechanisms we used hydropercussion following scheme of the equipment, which is part of the laboratory stand: model hydropercussion mechanism with variable frequency; measuring unit; vibrator.

The experimental work was carried out by the impact model hydropercussion mechanism in the rock under static and dynamic loading. The samples of rock were selected granite and marble, as a breed with high hardness category. Induction vibrator (vibration sensor) converts mechanical vibrations into electrical signals proportional to the vibration. When measuring the amplitude of the vibration sensor signals through an integrator fed to an analog-digital converter (ADC). ADC output signal is fed to an electronic counter and displayed on digital display then. In laboratory tests monitored the following parameters: frequency of attacks, the amplitude of the dynamic and static load, the depth of implementation, deployment time, the amount of power model vibrousilitelya. Model vibrousilitelya had three modes: shock; impact-rotary; rotational.

For measuring the vibration measurement system used laboratory bench provided vibration pick, analogotsifrovym converter, electronic counter signals. The experimental work was carried out by exposure to vibrousilitelya rock under static and dynamic loading. Chart speed depending on the frequency of introduction vibrousilitelya for granite in the shock-rotational mode is shown in Figure 1. Dots denote the experimental values, which are approximated by a polynomial trend line (shown by the solid line). Here is the resulting regression equation:
y = -01E - 0,8 x4 + x3 9E - 0,6 -0.002h2 + 0.1757 x+ 1.0162
The value of the reliability of approximation of D2 was 0.8933. The diagram shows that the rate of introduction into the granite vibrousilitelya significantly affect the speed of implementation. Thus, in the range of 5 to 111 Hz rate increases further from 111 to 150 Hz, starting a small decrease in velocity and, finally, in the range of 150 to 220 Hz - stabilization values. Speed the introduction of a marble at vibrousilitelya udarnovraschatelnom mode is irrelevant, which is almost an order of magnitude lower than for the granite under similar conditions.

Nevertheless, the dependence of the introduction of frequency is also clearly seen, namely, with increasing frequency increases the speed. These tables were not reflected in the diagram (Fig. 2.) Also give the regression equation:
y = -2E -0,8x3 -1E - 0,6x2 + 0,0035x + 0,003
and the magnitude of the reliability of approximation of R2 = 0.8313. Depending on the speed of implementation vibrousilitelya frequency effects in shock mode, granite and marble are the diagrams (Figures 3 and 4.) Note chtotendentsiya to increase the speed of implementation, depending on the frequency of exposure remains.

Figure 1. The dependence of the rate of introduction of vibrousilitelya in granite on the frequency of the impact of shock-rotary mode

Figure 2. The dependence of the rate of introduction of a marble vibrousilitelya impact on the frequency of shock-rotary mode

Figure 3. The dependence of the rate of introduction into the granite vibrousilitelya the frequency of exposure in shock mode

Figure 4. The dependence of the rate of introduction of a marble vibrousilitelya the frequency of exposure in shock mode.

In studying the dependence of the rate of introduction of vibrousilitelya granite exposure on the frequency of shock-rotational mode, found that after the values of 100-200 Hz, a significant increase in speed of introduction is not observed, however, is its gradual decline (Fig. 4). This is reflected in other charts. Laboratory studies revealed the dependence of the rate of drilling on the applicable regime. For the same rock were considered three modes of drilling - rotary, hammer and rotary shock. In the rotational mode, which in actual drilling conditions corresponds to the case when the cutters are worn out, without teeth, adoption rate was so low that it is not measurable. In view of this regime was considered inefficient and not further investigated. In shock mode (exposure was carried out in the longitudinal direction, in real terms corresponds to work well without a hammer bit rotation) speed of adoption was low. Shock-rotational mode, in real life he was compared with drilling vibrousilitelem at which the impact effect on the bit at a time when the bit is located in the rotational motion. This mode gives you several times the speed of implementation, and impact than rotational. So, depending on the speed of the tables in the introduction vibrousilitelya granite can be seen that when the shock mode at a frequency of 100 Hz - Pud = 1,15 ? 0-3 m / s, udarnovraschatelnom mode Ouvr 6,4430-3 = m / sec. Marble at the same frequency Oud = 0.09 3.30 m / s = 0.25 Ouvr 3.30 m / sec. When comparing the main results of the most effective, in terms of speed drilling of rock, is udarnovraschatelny mode. Comparison of results of the introduction of speed in the granite at udarnovraschatelnom and shock mode.

The laboratory experiments showed that at a constant value: the load, exposure time, a rock sample, the frequency of exposure - the shock-rotary drilling mode provides several times the speed of deployment than the shock, and at constant values: mode, the sample rocks dynamic load, exposure time - it turned out that the adoption rate increases with the frequency of exposure. But, since the frequency of 145 Hz (in shock mode) and 111 Hz (udarnovraschatelnom mode) significantly increase speed of introduction were observed. As can be seen from the graphs, with increasing frequency of exposure after 145 Hz does not increase the speed of implementation. This is due to a certain extent, with decreasing duration of contact of the indenter with the breed, there is a kind of "hang" of the indenter. To increase the speed of drilling, especially rotary should be developed naddolotnye vibrousiliteli with a frequency range up to 145 Hz. It is desirable that these tools are used to dynamic effect of the rock, in this case, the effect should be better.