Advances in Numerical Modeling of Downhole Dynamics for Perforated Well Completions

Shide

et al. 2017

Shock and Vibration

A model of a multibody system is established to investigate the dynamic response of an oil tube-shock absorber-perforating gun system in downhole perforation-test joint operation. In the model, the oil tube and perforating gun are modeled as elastic rods and the shock absorber is modeled as single particle system with damping and a spring. Two force continuity conditions are used to simulate the interactions among the three components. The perforation impact load is determined by an experiment of underwater explosion of perforating bullets. Using the model, the effects of charge quantity of perforating bullet, the number of shock absorbers, and the length of oil tube on the dynamic response of oil tube and packer are investigated. On this basis, a basic principle of the combination design of shock absorber and oil tube is proposed to improve the mechanical state of downhole tools. The study results can provide theoretical support for the design of downhole perforation-test joint operation.

Section: Introductionmentioning

confidence: 99%

Study on Dynamic Response of Downhole Tools under Perforation Impact Load

Shide

et al. 2017

Shock and Vibration

“…Some complex non-linear problems with high calculation accuracy have been solved with the premise of adapting to various complex mathematical models. The numerical simulation has many advantages and has become an effective means of piercing engineering analysis, in which the whole dynamic process can be presented by numerical simulation [26,27].…”

Section: Modeling and Meshingmentioning

confidence: 99%

Numerical Investigation of Downhole Perforation Pressure for a Deepwater Well

Qiao

Zhang

et al. 2019

Energies

During the production of deepwater wells, downhole perforation safety is one of the key technical problems. The perforation fluctuating pressure is an important factor in assessing the wellbore safety threat. Due to difficulty in describing the downhole perforation pressure by using the existing empirical correlations, a prediction model based on data fitting of a large number of numerical simulations has been proposed. Firstly, a numerical model is set up to obtain the dynamic data of downhole perforation, and the exponential attenuation model of perforation pressure in the wellbore is established. Secondly, a large number of numerical simulations have been carried out through orthogonal test design. The results reveal that the downhole perforation pressure is logarithmic to the total charge quantity, increases linearly to the wellbore initial pressure, shows an exponential relationship with downhole effective volume for perforation, and has a power relationship with the thickness of casing and cement as well as formation elastic modulus. Thirdly, the prediction of perforation peak pressure at different positions along the wellbore agrees well with the field measurement within a 10% error. Finally, the results of this study have been applied in the field case, and an optimization scheme for deepwater downhole perforation safety has been put forward.

SPE International Conference and Exhibition on Formation Damage Control

“…Over the past few years, several successful validations using high-speed gauge data and other experimental observations have been conducted (Schatz et al 1999and 2004, Schatz. 1992, Schatz et al1989, Bale et al 2014. A generic well configuration model used in the software is shown in Fig.…”

Section: Risk Mitigation and Modelingmentioning

confidence: 99%

Field Application Study of Zinc Based, Low Debris Perforating Charges

Zuklic

Myers

Satti

2016

Self Cite

All perforating operations cause debris, which can lead to wellbore restrictions, choked downhole hardware, plugged perforations, formation damage and operational problems throughout the installation of the completion. As a result, the industry has taken significant efforts to develop low-debris perforating systems. Low debris perforating techniques are important in maintaining a clean and productive perforation tunnel, as well as helping to reduce the risk of operational issues associated with debris during subsequent downhole tool operations. This risk minimization becomes even more important in complex completions with long zones at high shot densities (as often seen in sand control completions), in stacked completions where perforating on top of packers is required, and in horizontal completions, where debris can't fall into a sump area.One of the common methods for reducing the effect of perforating debris has been the use of zinc cased perforating charges. However, any low-debris system must also still create the optimum perforation in terms both of tunnel dimensions (maximum depth and diameter) and tunnel clean-up (minimum debris / reduced perm zone). Further, to maintain the connectivity of the perforation, consideration must be given to how the debris is handled after the perforating event and to potential interactions among the perforating debris and the wellbore and reservoir fluids. Extensive lab studies have examined all the effects of zinc perforating charges in these areas, but it is also critical to properly apply this to field scale applications through procedural examination.This study seeks to examine effects of perforating debris on field mechanical operations comparing different types of perforating debris. A comparison versus conventional steel-cased charges is also presented in terms of charge performance and dynamic clean-up effects of low-debris zinc charges. Further, an examination of chemical interactions of these low-debris systems in the field will be presented, and most critically, a comparative evaluation of procedural decisions and methods will be presented to show an optimum application of lab learnings to field scale applications. This paper also presents several case histories of wells that have been successfully completed using low debris perforating gun systems with zinc cased charges. Critical aspects of minimizing and managing debris, well productivity and other operational successes will be presented as part of the case histories.