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This paper presents the experimental study of hole quality parameters in the drilling of titanium alloy (6Al-4V). Titanium alloy plates were drilled dry using three types of solid carbide drills i.e. 2-flute helical twist drill, straight flute and three-flute drill. The objective was to study the effects of process parameters like feed rate, speed and drill bit geometry on the hole quality features. Typical hole quality features in a drilling process are the hole quality measures such as surface roughness, hole diameter, hole roundness and burr height. The results indicate that proper selection of speed, feed rate, and drill geometry can optimize metal removal rate and hole quality.

The competitive market has forced the industry to develop methodologies to reduce lead-time of the products without sacrificing quality. One of the major metal removal operations in the aerospace industries is drilling. Over 100,000 holes are made for a small single engine aircraft. Naturally, demand for faster production rate results in the demand for high-speed drilling. But the cost of hole-making operations becomes a significant portion of the total manufacturing cost. This paper discusses the high speed drilling of Al-2024-T3 alloy, the effect of feed and speed on hole quality features like oversize, roundness error, burr height and surface roughness.

A generalized upper bound model for calculating the chip flow angle in oblique cutting using flat faced tools with single cutting edge and multiple or curved cutting edges has been developed. The chip flow angle and chip velocity are obtained by minimizing the cutting power with respect to both these variables. The chip flow angles predicted by this model show good agreement with experimental values of chip flow angles for various tool geometries and cutting conditions. The model has the potential to be extended to the more complex machining processes such as drilling and milling.

Composites are finding more and more applications in the aircraft industry. Drilling good quality holes is a major challenge for the manufacturing industry. The major factors which have an effect on hole quality are cutting parameters like speed and feedrate, machine rigidity, tool material, workpiece material, and tool geometry. The hole quality was studied by measuring the hole diameter and visually observing other parameters like shape and fiber breakout. Force analysis indicates that thrust increases with an increase in feedrate. Speed does not seem to have a very significant effect on thrust. The tool geometry plays a very important role in fiber pullout.

The present scenario of increasing the production rates in drilling demands high speed drilling while at the same time maintaining the quality of the drilled holes. Of the many factors that affect the high-speed drilling process, such as speed, feed rate, material of drill and work piece, and drill geometry this study attempts only to study the effect of drill geometry in high-speed drilling of aluminum sheet metal. In the Experiments conducted, different speeds, feed rates and drill bits of varying geometry are utilized in order to study their effects on hole quality as it relates to hole diameter and burr formation. Also the variation of thrust and torque with increase in speed over a speed range of 6,000 to 30,000 rpm has been studied.

Aerospace manufactures purchase millions of drill bits each year for the manufacture of large aircraft structures. This paper describes an ongoing research project for the development of an automated system to detect poor quality drill bits before they are put to use.

Drilling is one of the most widely applied manufacturing operations. Millions of holes are drilled today in manufacturing industries especially in aerospace industry where high quality holes are essential. Rejection and rework rate of the products because of the bad hole is quite high. In this research graphite/honeycomb composite material and aluminum sheet metal has been used. The results show that drill geometry, speed and feed rate have substantial effects on the hole quality and also there was gradual variation of the thrust and lateral forces with feed rates.

Since riveting operations on airplane panels are usually performed manually by skilled workers and unrecoverable tolerances or errors are possible. In this paper, a semi-automated riveting system, which improves the product quality, and reduces cost, is proposed. The system setup is illustrated while related technology is described. The system uses optical equipment along with computer vision technology to assist riveting operators to find the locations of the rivets automatically, which may help reduce some setup procedures for riveting operations.