scholarly journals Propagation of Measurement-While-Drilling Mud Pulse during High Temperature Deep Well Drilling Operations

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Hongtao Li ◽  
Yingfeng Meng ◽  
Gao Li ◽  
Na Wei ◽  
Jiajie Liu ◽  
...  

Signal attenuates while Measurement-While-Drilling (MWD) mud pulse is transmited in drill string during high temperature deep well drilling. In this work, an analytical model for the propagation of mud pulse was presented. The model consists of continuity, momentum, and state equations with analytical solutions based on the linear perturbation analysis. The model can predict the wave speed and attenuation coefficient of mud pulse. The calculated results were compared with the experimental data showing a good agreement. Effects of the angular frequency, static velocity, mud viscosity, and mud density behavior on speed and attenuation coefficients were included in this paper. Simulated results indicate that the effects of angular frequency, static velocity, and mud viscosity are important, and lower frequency, viscosity, and static velocity benefit the transmission of mud pulse. Influenced by density behavior, the speed and attenuation coefficients in drill string are seen to have different values with respect to well depth. For different circulation times, the profiles of speed and attenuation coefficients behave distinctly different especially in lower section. In general, the effects of variables above on speed are seen to be small in comparison.

2021 ◽  
Vol 66 (05) ◽  
pp. 192-195
Author(s):  
Rövşən Azər oğlu İsmayılov ◽  

The aricle is about the pipe stick problems of deep well drilling. Pipe stick problem is one of the drilling problems. There are two types of pipe stick problems exist. One of them is differential pressure pipe sticking. Another one of them is mechanical pipe sticking. There are a lot of reasons for pipe stick problems. Indigators of differential pressure sticking are increase in torque and drug forces, inability to reciprocate drill string and uninterrupted drilling fluid circulation. Key words: pipe stick, mecanical pipe stick,difference of pressure, drill pipe, drilling mud, bottomhole pressure, formation pressure


2013 ◽  
Vol 753-755 ◽  
pp. 130-133
Author(s):  
Hui Hong Luo ◽  
Ze Hua Wang ◽  
Yu Xue Sun ◽  
Han Jiang

Focus on the high temperature rheological stability and the fluid loss control of resistance to high temperature drilling fluid system, further determine system formula and the formula of the high temperature drilling fluid system should be optimized. Eventually, a kind of organo-silica drilling fluid system of excellent performance which is resistant to high temperature of 220 degrees has been developed, and the system performances have been evaluated. The high temperature-resistant organo-silica drilling fluid system is of good shale inhibition, lubricity and borehole stability. The fluid loss is low and the filter cake is thin and tight, which can effectively prevent bit balling. The sand-carrying ability is good and the rheological property is easy to control. The performances of drilling fluid remain stable under high salinity and the system can resist the pollution of 6%NaCl and 0.5%CaC12. The materials used in this system are non-toxic, non-fluorescent and suitable for deep well drilling.


Author(s):  
Harry Schoeller ◽  
Shubhra Bansal ◽  
Aaron Knobloch ◽  
David Shaddock ◽  
Junghyun Cho

Lead-free solders have garnered much attention in recent years due to legislation banning the use of lead in electronics. As use of lead solders is phased out, there is a need for lead-free alternatives for niche applications such as high temperature environments where traditionally high lead solders are used. Electronics and sensors exposed to high-temperature environments such as those associated with deep well drilling require solder interconnects that can withstand high thermal-mechanical stresses. In an effort to characterize solder alloys for such applications, this study focuses on deformation behavior of the Sn95-Sb5 solder under high-temperature exposures (from 298°K to 473°K). As compared to conventional high-temperature Pb-based solder 90Pb–10Sn, Sn95–Sb5 exhibited very high tensile strength and modulus, as well as superior creep properties despite its lower melting temperature. Importantly, high-temperature deformation was shown to be influenced by the presence of the second phase (SnSb) distributed within the Sn-rich matrix. These second phase precipitates appeared to be dissolved into the Sn-rich phase above 453°K, which converted the solder into a single-phase alloy and resulted in a change in its deformation mechanism. Furthermore, as the service temperature is of such high homologous temperature (T > 0.5Tm), creep deformation will contribute significantly toward the life of the solder joint during thermal cycling. In order to characterize the creep behavior and to identify controlling mechanism(s), creep tests were carried out, from which the stress exponent and activation energy were determined. In this study, detailed microstructures under high-temperature are presented in conjunction with the corresponding mechanical behavior to further understand the controlling deformation mechanisms.


2011 ◽  
Vol 422 ◽  
pp. 10-16
Author(s):  
Fu Hua Wang ◽  
Rui He Wang ◽  
Xue Chao Tan

With the development of deep well drilling technology, a new HTHP (High Temperature High Pressure) experimental apparatus LH-1 was developed to meet the need of research and evaluation of deep well drilling fluid. With the advanced dynamic seal technology, mechanical transmission and data sensing technology, this new apparatus has many kinds of HTHP testing functions in a body and could evaluate manifold performances at the dynamic state of high temperature and high pressure including HTHP dynamic or static filtration test, high temperature dynamic scattering test of drilling cuttings, HTHP dynamic sealing and plugging tests, ultra HTHP aging test and so on. The lab tests show that the new apparatus gains such advantages as novelty of the design, stability of the performance, accuracy and reliability of the experimental data and facility of the operation. Having overcome the defections of the old apparatuses, the new device can provide a new means of experimental researches for the evaluation of HTHP comprehensive performance of deep well drilling fluid.


2021 ◽  
Vol 2093 (1) ◽  
pp. 012001
Author(s):  
Xiaopeng Lu ◽  
Hualin Liao ◽  
Huajian Wang ◽  
Wenlong Niu ◽  
Jiansheng Liu

Abstract The longitudinal vibration of the bottom drill string is violent and the law is complex during the deep well drilling. The vibration of the drill string brings many adverse effects on the drilling pipe fracture and bit trampoling. Generally speaking, the effective way to control the vibration of drill string is to install damping device in bottom hole. The research group proposes a device that uses the longitudinal vibration energy of the deep well drill string to modulate the impact dynamic load, which converts the vibration energy of the downhole drill string that is not conducive to drilling into the mechanical impact energy that improves the rock breaking capacity of the bit. The impact load modulation device can use the drill string to apply the “mechanical WOB” and the differential pressure between the upper and lower piston to produce the “hydraulic WOB”, The simulation results show that the adjustable range of output load is 2 ~ 7T, and the change of each time is about 2T. The modulation law of impact load under the influence of longitudinal vibration of drill string and different parameters is analyzed. Through ground experiment and simulation, the damping performance and speed-up effect of the modulation device are compared and analyzed, and the impact load output characteristics of the device are analyzed, which provides a thinking for the design of damping and pressurization tools.


2021 ◽  
Vol 26 (2) ◽  
pp. 43
Author(s):  
Constantino Grau Grau Turuelo ◽  
Cornelia Breitkopf

The prediction and control of the transformation of void structures with high-temperature processing is a critical area in many engineering applications. In this work, focused on the void shape evolution of silicon, a novel algebraic model for the calculation of final equilibrium structures from initial void cylindrical trenches, driven by surface diffusion, is introduced. This algebraic model provides a simple and fast way to calculate expressions to predict the final geometrical characteristics, based on linear perturbation analysis. The obtained results are similar to most compared literature data, especially, to those in which a final transformation is reached. Additionally, the model can be applied in any materials affected by the surface diffusion. With such a model, the calculation of void structure design points is greatly simplified not only in the semiconductors field but in other engineering fields where surface diffusion phenomenon is studied.


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