In all well completions (oil and gas fields), effective cement job is necessary for zonal isolation. Failure of cement annulus because of large stresses has been reported in various studies, requiring huge costs in remedial intervention. Swellable packers have emerged as a new manufacturing equipment/technique able to replace conventional cement completion. These packers are custom-manufactured by vulcanizing specially developed swelling elastomer elements onto petroleum pipes. Especially designed and manufactured to suit a particular set of downhole conditions, swell packers are being used in a variety of petroleum applications such as zonal isolation and water shutoff in fractured reservoirs, slimming down of oil wells through replacement of conventional cementing, sand screening, reservoir compartmentalization, etc. Performance analysis and seal design improvement is not possible without reliable information about material response of swelling elastomers. This article summarizes the results of a series of tests performed to determine the swelling behavior of a water-swelling and an oil-swelling elastomer, with and without acid induction. Experimental setup was designed in consultation with petroleum and rubber engineers. Volume, thickness, and hardness of elastomer samples were measured before swelling and periodically after swelling over a one-month period. Test conditions were chosen to replicate actual oilfield conditions.

Nonhomogeneous metal flow through an extrusion die can directly affect product quality, productivity, and die life. The complexity of a die profile is an indicator of how difficult it is to extrude the profile. Some investigations about the effect of die complexity on extrusion pressure, product quality, and die life can be found in the published literature. However, the effect of profile complexity on metal flow through the extrusion die has not been explored much. Such a study can directly contribute toward die design improvement and reduction of extrusion defects related to metal flow. This article investigates the effect of shape complexity on the dead metal zone (DMZ) and metal flow through cold extrusion experiments and finite element simulations on some solid profiles. Experiments were performed using flat-face dies of different complexities and different billet materials. 2D and 3D finite element simulations were carried out. One significant conclusion is that currently existing definitions of extrusion shape complexity cannot satisfactorily explain the variations in DMZ size under different conditions. Factors such as die profile symmetry and extrusion ratio may play significant roles in the formation of DMZ and distortion of metal flow through the die.

Extrusion is a very popular and multi-faceted manufacturing process. A large number of products for the automotive, aerospace, and construction sectors are produced through aluminum extrusion. Many defects in the extruded products occur because of the conditions of the dies and tooling. The problems in dies can be due to material issues, design and manufacturing, or severe usage. They can be avoided by maintaining the billet quality, by controlling the extrusion process parameters, and through routine maintenance. Die problems that occur on a day-to-day basis are mostly repairable and are rectified through various types of die correction operations. These defects and repair operations have not been reported in detail in the published literature. The current paper presents an in-depth description of repairable die defects and related die correction operations in metal extrusion. All major die defects are defined and classified, and their causes, preventive measures, and die correction operations are described. A brief frequency-based statistical study of die defects is also carried out to identify the most frequent die corrections. This work can be of direct benefit to plant engineers and operators and to researchers and academics in the field of metal extrusion.

Many automotive components that were earlier made of cast iron are now using aluminum alloys due to their lower weight, better castability, corrosion resistance, and strength at elevated temperatures. Heat treatment is a major processing step in the manufacturing of aluminum-based piston components. The current paper discusses an optimum heat treatment strategy for AC8H aluminum alloy for improved performance. Solutionizing (for homogenization) is followed by aging at different temperatures. Tensile, impact, and hardness tests are performed on untreated and heat treated specimens. Structural analysis (microscopy) is done to understand the changes in mechanical properties. Fractography is also carried out to identify fracture mechanisms under gradual and impact loads. Yield strength, ultimate strength, hardness, and impact toughness show significant increase when aged at 150°C and 175°C (maximum values of 80 MPa, 177 MPa, 28 HRA, and 5.25 J respectively) but decrease at 200°C. SEM micrographs of fracture surfaces show ductile, brittle, and mixed-mode failure patterns for different samples. Observed structural changes are in line with changes in the mechanical properties. It can be concluded that optimum combination of properties is obtained when specimens are aged at 175°C. These findings are of direct utility for academicians, researchers, and practitioners involved in design and manufacture of automobile and other engineering components.