The use of composite materials and composite stackups in aerospace and automotive applications has been and will continue to grow at a very high rate due to the high strength and low weight of the materials. One key problem manufacturers have using this material is the ability to efficiently drill holes through the layers to install fasteners and other components. This is especially true in sta...

The San Andreas Fault Observatory at Depth provides the most comprehensive set of data on the structure and dynamics of the San Andreas fault. We use two independent experiments recorded by the seismometer arrays of the SAFOD Pilot and Main Holes to resolve the localized structure of the San Andreas fault zone and of an intermediate fault zone at depth. From Pilot Hole recordings of the drillin...

Composites are more and more increasing their importance as one of the most interesting group of materials, because of their unique properties. Hole drilling operations are common in composite parts to facilitate fastener assembly. As composites are non-homogeneous this operation causes some damages like delamination and others that reduce bearing and fatigue strength of the composite part. A p...

This is a summary of state of the art horizontal well technology and a review of the economic benefits of horizontal wells. The paper describes various reservoir applications of horizontal wells from primary recovery to EOR applications. The paper includes field examples of different applications. . Although horizontal wells have been drilled as early as 1927, the major thrust of drilling horiz...

This paper analyses the non linear properties exhibited by a drill string system under various un balanced mass conditions. The drill string is affected by continuous friction in the form of drill bit and well bore hole interactions. This paper proves the origin of limit cycling and increase of non linearity with increase in speed of the drilling in the presence of friction. The spectrum of the...

We present a drilling method that is based on the phenomenon of local hot spot generation by near-field microwave radiation. The microwave drill is implemented by a coaxial near-field radiator fed by a conventional microwave source. The near-field radiator induces the microwave energy into a small volume in the drilled material under its surface, and a hot spot evolves in a rapid thermal-runawa...

Prediction of surface roughness is essential in any machining process as it plays a vital role in determining the quality of components. The present work involves the development of an empirical model for surface roughness of a non-traditional hole-making method, friction drilling process based on a recently emerged evolutionary approach called Genetic programming (GP). The parameters such as d...

To ensure safe and stable drilling operation, bottom hole pressure (BHP) should be kept within some region. However measurement of the BHP is sometimes not available or reliable, especially when the circulation is low, e.g., during pipe connection procedures. This paper presents the application of a moving horizon estimation (MHE) method for online estimation of the BHP during petroleum drillin...

The distinctive characteristics of carbon fibre reinforced plastics, like low weight or high specific strength, had broadened their use to new fields. Due to the need of assembly to structures, machining operations like drilling are frequent. In result of composites inhomogeneity, this operation can lead to different damages that reduce mechanical strength of the parts in the connection area. F...

We have devised a method, based on a parametric array concept, to create a low-frequency (300-500 kHz) collimated ultrasound beam in fluids highly attenuating to sound. This collimated beam serves as the basis for designing an ultrasound visualization system that can be used in the oil exploration industry for down-hole imaging in drilling fluids. We present the results of two different approac...