Negative pressure wave is a popular method to detect the occurrence and location of leak incidents in oil/gas pipeline. Three core technical challenges related algorithm are discussed this paper. The first data quality. balance between noise level locating precision filter design. second one dynamic slope anomaly detection, whence bi-SPC (Static Process Control) algorithms proposed make threshold be adaptive. third false alarm caused normal working condition changes. Multiple-sensor paring...

In the development of unconventional shale play, simulation performance for wells needs to incorporate sufficient complexity in geology take fully into account variabilities petrophysical and geomechanical properties. These parameters controlling effective stimulated rock volume (eSRV) represent heterogeneity strong‐layering nature reservoirs: high inter‐bedding anisotropy, flow behaviours pre‐existing geological disconnections (bedding planes, faults, fissuring, natural fractures). This...

As an important unconventional gas resource, shale has become part of production in recent years with the advantage horizontal well drilling and large-scale multi-stage hydraulic fracturing completion technologies. The reservoir numerical simulation advances were reviewed a fractured was performed to qualitatively modeling productivity over-pressured based on actual properties parameters. A single model established basis dual-porosity logarithmically spaced grid refinement. comprehensive...

Abstract The understanding of acid rock reaction kinetics is the basis for proposal carbonate acidizing and fracturing. So far, study in reservoirs mostly focused on limestone reservoirs. difference characteristics between dolomite obvious. In order to clarify boundaries control models mechanisms reservoirs, guide optimization fracturing with different contents. experimental was completed cores mass fraction, corrosion mechanism analyzed by scanning electron microscope. equation under...

Flexible pipeline has been widely used in offshore engineering. Comparing to steel pipe, flexible subsea some merits such as anti-corrosive, easy laying and recycling. So it is suitable be flowline shallow water. Especially there are lots of marginal oil fields water China. Different from deepwater dynamic riser, pipe for applications a low requirement resisting external pressure. On the other hand, need satisfy tensile property during installation. Therefore, kind simple economical can...

Abstract To achieve economic and efficient utilization of marginal oil zones remaining in low-permeability reservoirs, a directional wellbore stimulation technology with strong targeting controllability is proposed. This integrates drilling, completion, functions. For carbonate hydraulic fracturing or acid are necessary to economically viable development. However, for reservoirs multiple layers, thin single those close edge bottom water, lacks advantages targeted economical modifications...

Chinese text automatic proofreading opens up broad possibilities for the application of natural language processing. According to distribution single-character after word segmentation in with characteristic errors and character trigram model, presents an effective algorithm. Experiments show that our method achieves better precision recall.

The Ordovician buried-hill carbonate reservoir in the northern Jizhong Sag of China is seen with abundance hydrocarbon resources. Nonetheless, attempts multiple stimulation technologies have all failed to make breakthrough, due its lithological complexity (mixture dolomite and limestone), ultra-high temperatures (180°C) high in-situ stress gradients (0.023 MPa/m), Given aforementioned geological challenges, evaluation, technology optimization plan design starting from characteristics been...

In order to reasonably select the proper suppliers for enterprises in China, this paper presents a supplier comprehensive evaluating index system through analysis of all kinds factors. The method data envelopment analysis, which has characteristics such as multi-input, multi-output and poly-objectives evaluated objects, is applied into selection model based on it established. Through using method, be chosen are falling two kinds: technical efficiency inefficiency, make an objective select....

Based on the characteristics of carbonate reservoirs, staged-fracturing technology for horizontal wells was adopted to effectively drain reservior. Fracture parameters including orientation, number, length, fracture conductivity and distribution were optimized, accordingly a hydraulic fracturing design developed. Applied in oilfield, this method proved be effective oil production. Therefore, it can provide theoretical guidance stage-fractured wells.

In this study, 6 prefabricated reinforced concrete columns with different lengths of connectors and thicknesses the steel plate used in 1 cast‐in‐place column were made, then these specimens tested under low cycled reversed loading experiment to study seismic performance mortise tenon connections. The failure mode, bearing capacity, ductility, stiffness degradation, energy dissipation analyzed. results show that compared specimens, capacity fabricated specimen is reduced by 5.77%–16.67%, but...

Abstract This paper studied a new fracturing fluid based on supramolecular complex between associative polymer and viscoelastic surfactant (VES). The combination of VES synergistically enhances the viscosity several times more than that individual components alone. system was optimized by experimental design. microstructure wormlike micelle formation verified electron microscopy. proppant transport test in large-scale fracture simulator showed good suspension ability. After fracturing, nano-...

Abstract The marginal block Zana oil field is a typical hard-to-produce carbonate reservoir, thin net pay, poor reservoir physical properties, low pressure, strong heterogeneity, bottom water and gas cap risks coexist, it difficult to obtain profitable production in conventional development model. In order realize its high-efficiency development, research on integrated geological engineering technology was carried out. First, the static dynamic data analysis combined with pilot well used...

The heat transfer coefficient K value and thermal inertia index D plays an important role in wall insulation performance. This paper use the palisade structure of performance analysis evaluation program K-value which developed by Chinese academy sciences, taking Changsha area climate condition as example ,to simulated analyzed hypothesis single material composite wall. So we can obtain on most effective range.