Papers by Author: Zheng Liang

Abstract: Slant-hole drilling rig, which can be used to drill inclined well from the ground, is used widely. During designing and research, it is very important to meet working reliability and requirement under various loads and working conditions. As for the complex structure of slant-hole drilling rig, we cannot get the real analytical solutions at present condition. Therefore, the paper establish the three-dimensional finite element models which are about the lifting process and working conditions of slant-hole drilling rig, study the applied loads of each working condition and analyze the stress-strain regulation of slant-hole drilling rig and its influential factor. Based on the analytical results of deformation and stress, an improvement scheme for the slant-hole drilling rig’s structure can is put forward.

Abstract: As a convenient, efficient, secure and high working quality casing running tool, the top drive casing running tool (CRT) has been recognized by the enterprises and users of petroleum mechanism and instrument. Slips system is an important subassembly of CRT, which directly decides the reliability, security and casing surface quality while running or drilling with casing. Based on finite element method and contact mechanics, the research model of CRT's slips system has been established and the contact influence has been studied. The effects of front angle, bottom angle and teeth interval on the slips contact interface are analyzed. As a result, the optimal axial tooth form parameters are recommended. Based upon casing intensity verification, the analytical approach to determine the slips total length has been introduced under a given maximal weight of casing string.

Abstract: In upstream petroleum industry, one of the major operations that can potentially impact the environment is drilling. A major component of the wastes generated during drilling are the rock cuttings and the drilling fluids. The drilling fluids can have different chemical composition and various additives. Spilled or improperly disposed drilling wastes have the potential to harm plants and animals, and it should be managed to minimize risk to human health and the environment. The increasing environmental legislation surrounding drilling operations has led to a rapid rise in drilling waste management spending by operators. Managing wastes to minimize their harm potential to health and environment is the international concern and requires efficient management of wastes to reduce the environmental impacts. The management and control of waste which develops from the strategy can also have the beneficial effect of reducing the number of health related issues.This paper presents the waste management including recognizing the waste sources and methods which are used to minimize the impaction to environment and human health from drilling waste. This paper also reviews the strategy of drilling waste management which could reduce the number of health related issues as well as environment pollution.

Abstract: On the base of numerical simulation and theoretical analysis, the flow field of a conventional single-tangential-inlet Hydrocyclone and a newly put forward axial-symmetry double-tangential-inlet hydrocyclone were contrasted. The study shows that the inlet structure of the Hydrocylone has a great influence on the radial velocity of the flow field in the hydrocyclone and that the radial velocity in the hydrocyclone with single-tangential-inlet is not symmetry about the axis of the hydrocyclone; and on the other hand the radial velocity in the hydrocyclone with axial-symmetry double-tangential-inlet is symmetry about the axis of the hydrocyclone. The magnitude of the radial velocity of the flow in the hydrocyclone with single-tangential-inlet is greater than that in the hydrocyclone with axial-symmetry double-tangential-inlet hydrocyclone, which means the hydrocyclone with axial-symmetry double-tangential-inlet has greater capability than the rival one with single-tangential inlet. The symmetry about the axis of the hydrocyclone of the radial velocity means the radial velocities in the place where the radio is the same are constant, which means the hydrocyclone has a great separation efficiency. The conclusion is that changing the conventional hydrocyclone into the one with axial-symmetry double-tangential-inlet structure can offer greater separation capability and efficiency.

Abstract: Abstract: On the basis of Reddy’s higher order shear deformation plate theory and the von Kármán’s geometry nonlinear theory, governing equations for nonlinear thermal buckling and post-buckling of symmetry angle-ply laminated composite beam subjected to a temperature rise are derived, in which the stretching-bending coupling terms produced by the non-homogenous distribution of the material properties are included. By using the shooting method to solve the corresponding nonlinear boundary value problem, numerical solutions for thermal post-buckling of symmetry angle-ply shear deformation laminated composite beam with its both ends immovably simply supported under uniform temperature rise are obtained. As an example, equilibrium paths and configurations for laminated composite beam paved in term of 45/90 are presented and characteristic curves of the nonlinear deformation changing with the thermal load were plotted. The effects of the geometric and physical parameters on the deformation of the beam are also examined. The theoretical analysis and numerical results show that different thermal expansion coefficient ratio, elastic moduli ratio, will influence of the non-dimension critical buckling temperature.

Abstract: Traction devices are power transmission components of railbound vehicle. This article discusses the gearbox mechanical properties numerical calculation and strength analysis. It established calculation model based on field test parameters. And it finished analysis about elastic deformation of large displacement and contact problem of nonlinear finite element method during numerical calculation. With comparison of energy strength theory and ASME VIII-2 standard, it chooses the suitable strength method for gearbox. With definition of key parameters, the mechanical properties numerical calculation results were given in different load conditions. According to displacement, strain and stress analysis, the gearbox strength is analyzed based on ASME VIII-2 standard. The results show: under field test loads, the gearbox satisfies strength requirement. But there is stress concentration phenomenon. During independent analysis process of gearbox, hanging and assembly, the results of displacement, strain and stress assume certain regularity.

Abstract: Natural gas downhole choke process inlet is high temperature and high pressure. Usually it can achieves 10~30MPa, while it will be higher in high pressure drilling well. It is installing thousands of meters underground. It is difficult carrying on field test during working process. These special situations make the choke outlet flow being complex, which includes expansion wave, compression wave, and energy transformation. The physical experiment is difficult. To be more accurately analyzing the compressible viscous turbulent motion of downhole choke internal flow field, this article uses RNG − model for three dimensional numerical simulation. It analyzes the result of flow field streamlines, velocity, Mach number, pressure, and temperature distribution. It analyzes the influence on hydrate formation of choke working process. Numerical calculation can provide useful reference for the prevention of natural gas hydrate formation and optimization design of downhole choke.