试井环空静压仪器在试井中的技术研究

试井工作当中需要通过环空静压仪器进行测试油套管环形空间的压力,能够为油田的生产提供资料,保证油田能够顺利生产。在测试的过程中往往会出现仪器缠绕的问题,出现这种问题就会导致测试结果不能为油田开采提供资料。因此只有采取合理有效的措施解除缠绕才能保证测试能够顺利进行,只有这样才能够完成测试任务。

Influence of patio on indoor environment in a Chinese traditional folk house in summer

A case study is performed on the influence of the patio on the indoor environment of a traditional folk house group,named Zhangguying village in Hunan province,in the summer of 2007.Measurements include indoor and outdoor air temperature,indoor and outdoor illuminance,indoor and outdoor air speed,and carried out from August 5th to 10th.The results show that the patio,acting as a ＂buffer zone＂,can reduce the ambient impacts on the indoor thermal environment of rooms because the temperature of the patio is lower than that of the outdoor temperature but higher than that of the rooms.The patio can improve the indoor lighting environment because the illuminance of the patio is lower than that of outdoor and higher than that of the rooms.But the effect is too limited,because the illuminance of the rooms is lower than the national standards.This study shows that the shading design is the primary consideration in this kind of climate.The wind speed of the patio is stable and similar to that of the hall and the stack effect of the patio is not obvious.It shows that the patio is useful for natural ventilation,caused by wind pressure,in summer.

预制井筒的结构设计方案

井筒式地下立体停车库具有占地小、对景观影响小的优点,是解决城市停车难题的一种方法,特别适用于建造于八、九十年代的老旧小区的停车库建设。预制井筒的设计方案,具有造价低、速度快、工业化程度高的优点。本文介绍了预制井筒的结构设计方法,与密度桥项目相比,预计土建造价可降低1/3。

Directional drilling in unstable environments

Directional drilling has been established in the coal industry as a viable means of gas drainage, exploration and water management. But the environment in and around coal seams is not always conducive to stable conditions while drilling and borehole stability after the drilling has been completed. This paper identifies the conditions which cause unstable drilling conditions and the various means which are used to attempt to manage or bypass those conditions. Ultimately, equipment does become bogged in these adverse environments and requires recovery by over-coring.

Influence factors on stress corrosion cracking of P 110 tubing steel under CO2 injection well annulus environment

Stress corrosion cracking （SCC） behavior of P 110 tubing steel in simulated C02 injection well annulus environments was investigated through three-point bent tests, potentiodynamic polarization and EIS measurements. The results demonstrate that SCC of P110 tubing steel could occur in acidulous simulated environment, and the sensitivity of SCC increases with the decrease ofpH, as well as increase of sulfide concentration and total environmental pressure. Both anodic dissolution and hydrogen embrittlement make contributions to the SCC. Adequate concentration of corrosion inhibitor can inhibit the occurrence of SCC on account of the inhibition of localized anodic dissolution and cathodic hydrogen evolution.

Comprehensive analysis of safe mining to heavy and steep coal seam under complex geophysics environment

In virtue of effect of N-S intensive ground stress and mining disturbance to +579E2EB_(1+2) mining site at Weihuliang Mine,the dip angle and section height is 65° and 52 m,respectively,the collapses happed frequently during mining.Firstly,mining condi- tions,spatial structure and parameters were investigated.Then physical simulation and dynamic numerical tracing and elaborate simulation relating roof and top-coal were ap- plied based on 2D-Block Program and quantitative regularity of stress at variable depths had been estimated.Furthermore,it was manifested that effective measures,i.e.,fast mining,control symmetrical top-coal-caving at dip and strike directions,optimizing ventila- tion system,active-stereo preventing gas were performed successfully in mining practice. Ultimately,the derived dynamic hazard were prevented so as to safety mining.

Gas and rock-bump hazard monitoring in the Polish mining

Described the main environmental hazards occurring in Polish undergroundmines and their continuous growth in recent years as well as equipment and systemswhich were used for monitoring mine air parameters and geodynamic phenomena.Thelatest versions of environmental hazard monitoring systems,having a form of a comprehensiveset of underground and surface equipment,are presented and their functionscharacterized.

Real-time Diesel Particulate Matter ambient monitoring in underground mines

A real-time Diesel Particulate Matter （DPM） monitor has been developed on the base of the successful National In- stitute of Occupational Health and Safety （NIOSH） designed Personal Dust Monitor （PDM） unit. The objectives of a recently completed Australian Coal Association Research Program （ACARP） study was to modify the PDM to measure the submicrometre fraction of the aerosol in a real-time monitoring underground instrument. Mine testing focused on use of the monitor in engineering evaluations of Longwall （LW） moves demonstrated how DPM concentrations from vehicles fluctuate under varying ventilation and operational conditions. The strong influence of mine ventilation systems is reviewed. Correlation between the current SKC DPM measurement system and real-time DPM monitors were conducted and results from eight mines show a correlation between elemental carbon （EC） and the new monitor DPM mass ranging from 0.45 to 0.82 with R2〉0.86 in all but two cases. This differences in suspected to be due to variations from mine to mine in aspects such as mine atmospheric contamination, vehicle fleet variations, fuel type, engine maintenance, engine combustion efficiency, engine behavior or interference from other submicrometre aerosol. Real-time monitoring clearly reflects the movement of individual diesel vehicles and allows pin-pointing of high exposure zones such as those encountered where various vehicles engage in intense work in areas of constrained or difficult ventilation. DPM shift average monitoring approaches do not readily allow successful engineering evaluation exercises to determine acceptability of pollution levels. Identification of high DPM concentration zones allows efficient modification of mine ventilation, operator positioning and other work practices to reduce miners＇ exposures without waiting for laboratory analysis results.

NONLINEAR ANALYSES OF VOID DIFFUSION MODEL AND ITS APPLICATION TO SUBSIDENCE PREDICTION

The void diffusion model for mining-effected strata can be analyzed by means of a nonlinear finite element method. This paper presents the fundamental principles of the analyses. The key to the analyses is the determination of roof subsidence and the nonlinear relationship between diffusion coefficient and subsidence. This paper discusses these problems and determines the coefficient for Pingdingshan mining district, with which several profiles are predicted. It is found that the predicted profiles are coincident with the corresponding field profiles.

Inhibition characteristics of circulating current in parallel inverter driving system of mine hoist

This research investigated the outputting circulation current inhibition characteristic which are controlled by the instantaneous feedback voltage in inverter parallel driving of the mine hoist. We established a transfer function of the parallel inverters controlled by the close-loop adjustment of instantaneous voltage feedback. The influence of the parameters of the close-loop feedback circuit to the inhibition effects to the outputting circulation current is observed. After analyzing the circulating current inhibition characteristics, the proportion integration （PI） controller is introduced into the close-loop adjustment by instantaneous voltage feedback. The characteristics equation is gained to determine the PI parameters by drawing the Bode plots. The inhibition effects of the proposed controller are examined by the established simulation model of parallel inverter system. The harmonic distortion rate at the outputting voltage frequency value of 4, 10, 20, 41 and 50 Hz, are all lower than 2.32 % by the instantaneous outputting voltage feedback.

Simulation and animation model to boost mining efficiency and enviro-friendly in multi-pit operations

A discrete-event system simulation and animation program was developed to enhance the efficiency of a truck-excavator operation and reduce the environmental impact of haulage in an open-cut coal mine with multiple-pit operations. In any mine, a key objective is to have sufficient equipment for production and not to have excess to where it becomes counterproductive. Due to the advent of responsible mining,environmental regulations, and eco-friendly practices, these factors must also be considered in the analysis. Simulation studies can be financially advantageous for both the optimization of existing mine operations and new development phases in a mine. This study is a new approach to use discrete-event system simulation for mine systems, in order to investigate and possibly reduce environmental impact considering mining haulage performance and production target. A hypothetical layout of a surface coal mine with two pit operations was used for the simulation and animation model. The simulation model includes the animation of the operation. Animation is helpful to enhance the benefit of a mine simulation model. GPSS/Hòand Proof Professionalòwere the software used for the investigation.

A new matrix-based mathematical model for determining unidirectional circuits in a ventilation network

The occurrence of local circulating ventilation can be caused by many factors, such as the airflow reversion during mine fire,the improper arrangement of local fan or underground fan station and the man-made error input of raw data before network solving. Once circulating ventilations occur,the corresponding branches in the ventilation network corresponding to the relevant airways in ventilation system form circuits,and all the direc- tions of the branches in the circuits are identical,which is the unidirectional problem in ventilation network.Based on the properties of node adjacent matrix,a serial of mathe- matical computation to node adjacent matrix were performed,and a mathematical model for determining unidirectional circuits based on node adjacent matrix was put forward.

Improvements of drilling fluid processing for cable-suspended electromechanical drills

Deep ice drilling in Polar Regions plays a key role in paleo-climate, microbiological and glaciological researches. For deep ice and subglacial coring the special purpose-built electromechanical cable-suspended drills with bottom-hole circulation are designed and explored. Used at present drilling fluid circulation systems are specified by very high fluid wastes during processing. Measurements in deep drilling projects in Antarctic and Greenland ice sheets showed that 25%-40% of the drilling fluid, pumped into the hole, is retrieved to the surface with cable and drill, and up to 45% of retrieved fluid goes to waste. This leads not only to increasing of the fluid consumption and cost of the project in general but also to severe contamination of air, surface and near-surface snow-firn layers at the drilling site. In order to reduce wastes and environmental impact, it is proposed to modify drilling fluid processing system by avoiding of evaporation and leakages of fluid as far as practicable. Drilling fluid is prepared and pumped into the hole according to predetermined program on semiautomatic mode, and volume and density of blended and pumped into the hole drilling fluid are measured continuously. Components of the drilling fluid are stored and mixed in the special closed containers equipped by pressure relief valves. Separation of drilling fluid from ice cuttings is carried out by two steps: firstly, fluid is separated with hydro extractor and then with thermal separator. To reduce the amount of removed drilling fluid with cable special squeezing collar is installed on the borehole mouth. All these arrangements are able to decrease drilling fluid wastes in many times.

Air flow calculation of reverse circulation drilling technique with air DTH hammer

Air DTH hammer has been successfully applied in minor-caliber solid mineral exploration,water-well drilling and other drilling areas. In order to expand the applications of the technology,the authors further studied the principle and analyzed the mechanism of reverse circulation drilling technique with air DTH hammer to get the perfect assembles of equipments by optimizing working parameters. No parameter seemed more important than the air volume because it could maintain the working performance stability. The minimum air volume is related to the parameters such as depth and pressure,which was calculated under the actual conditions. It was solved for the air injection flow tables of the air DTH Hammer working at the different pressures. According to the data tables,operators could adjust the air volume to meet the demand on this technique,which had a realistic guiding significance. So it could build up a set of systematic and complete hi-technique.

Analysis on Sustainable Development of CNPC Mud Logging Business

As oil and gas development gets more difficult, the market competition in engineering technology services tends to be fiercer. CNPC mud logging business is facing double challenges from tedmology and market. We analyzed both external and internal environment for CNPC logging business development, made clear the opportunities and challenges, gained insights in to the existing problems, and proposed countermeasu res from the aspects of management system, service mode, proyqtability, techniques and equipment, market expansion, and personnel training.

Design and construction of HYSY981

This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,concept design and combined basic design. The key technologies are the researches concerning global design,system integration,platform positioning,global performance analysis,structural strength and fatigue analysis,environment effect assessment of South China Sea,basin test and tunnel test,and construction technology of platform. Core technology of design and construction for the 6th deep water semi-submersible rig is held. Independent detail design and construction are also accomplished. These have improved technology of key equipment for China offshore oil exploitation.

An evaluation of a perfluoromethylcyclohexane(PMCH) permeation plug release vessel(PPRV) in a controlled turbulent environment

The use of sulfur hexafiuoride （SF6） as a tracer gas for analyzing underground mine ventilation systems has been practiced for over 30 years. As a result, the methods used to release, sample, and analyze SF6 are well accepted. As the complexity and size of underground mine ventilation networks increase, the ability of a SF6 to function as a convenient and rapid means of analysis diminishes. The utilization of multiple tracer gases can mitigate this by removing the need to purge the background presence of a tracer before conducting another release and allowing for a more comprehensive evaluation using multi-zone tech- niques. Recent studies have identified perfluoromethylcyclohexane （PMCH） as a possible supplement for SF6 in underground mine ventilation tracer studies. However, the deployment of PMCH remains a challenge because of this compounds physical properties. This paper evaluates a PMCH permeation plug release vessel （PPRV） under controlled turbulent conditions. The details of the experimental parameters used in the evaluation as well as a discussion regarding the performance of the PPRV are included.