Brookhaven National Laboratory was requested to conduct a literature survey for the best available cement to use in the proposed casing patch as part of the Geothermal Drilling Organization (GDO) project on remediation of deformed casings. A total of 50 wells has been identified with deformed production casing in Unocal’s portion of The Geysers geothermal field. Reduced internal diameter and ca...

When the thermal stresses induced in a geothermal well’s casing string exceed the yield strength of the casing material, the fatigue behavior of the latter can be defined as low cycle fatigue (LCF). The connection threads in the casing body amplify the local stress distribution and lower LCF resistance. A theoretical approach is presented to evaluate LCF resistance and compared with preliminary...

This paper analyzed the characteristics of managed pressure drilling (MPD) technology and impact of wellhead back pressure on the wellbore annulus pressure profile, and found that the application of this technology provides room for improvement to the current casing program design. Meanwhile, the equivalent density of drilling fluid in wellbore annulus needs to consider the impact of back press...

SUMMARY Detailed measurements have been made of the casing boundary layer flow before and after the nozzle blades of a single stage model air turbine. The measurements were made with the natural casing inlet boundary layer and two artificially thickened boundary layers. The results differ considerably from those usually obtained in two dimensional cascades. There was no sign of the usual second...

This research paper presents numerical studies of the characteristics of warhead fragmentation in terms of initial velocities, spray angles of fragments and fragment mass distribution of high explosive (HE) warhead. The behavior of warhead fragmentation depends on shape and size of warhead, thickness of casing, type of explosive, number and position of detonator, and etc. This paper focuses on ...

One of the major problems faced by the oilfields in the middle time is casing damage. The neural network, the improvement BP as well as the three-layer feed forward neural network applied in damage diagnosis is a key way to prevent damage. The formations of the damage are corresponded to the input vector. Factors such as casing age limit, strata stress, soaking time are described as real Number...

3.1 Overview 3.2 Overview of Nodal Analysis 3.3 Selection and Determination of Tubing and Production Casing Sizes for Flowing Wells Importance of Sensitivity Analysis of Tubing Size Sensitivity Analysis and Optimization of Tubing Size of Flowing Well Optimization Method Based on Surface Tubing Pressure Derived by Given Separator Pressure Optimization Method Based on the Given Wellhead Tubing Pr...

The present study explains a steady-state method of measuring convective heat transfer coefficient on the casing of an axial flow turbine. The goal is to develop an accurate steadystate heat transfer method for the comparison of various casing surface and tip designs used for turbine performance improvements. The free-stream reference temperature, especially in the tip gap region of the casing ...

In this paper, a simulation-based method is proposed for optimal placement of vibration sensors for the purpose of fault detection in a centrifugal pump. The centrifugal pump is modeled to investigate the effect of vane tip fault on fluid flow patterns numerically. Pressure pulsations are investigated at different locations at the inner surface of the pump before and after the presence of the f...