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The past five years have seen a significant improvement in the reliability and the acceptance of two‐dimensional abrasive waterjet (AWJ) cutting systems. Across all of the major industrial countries in Europe, one can now find any number of job shops or custom cutting centres offering AWJ cut parts. Three‐dimensional AWJ cutting systems were first introduced into the aerospace industry. The AWJ machines used to cut aerospace parts were mainly limited to large‐frame, cost‐intensive five‐axes units dedicated to the aerospace industry. Recently, a select few of the well‐established users of two‐dimensional AWJ cutting systems have acquired three‐dimensional AWJ cutting systems. New, lower‐priced systems combined with innovative configuration options, improved programming techniques, advanced automation and accuracy have taken three‐dimensional AWJ to another level. Discusses the recent developments in three‐dimensional AWJ systems.

A Renishaw TP2 touch trigger probe and an Optocator range‐finder are both incorporated in LK Tool's five‐axis measuring system.

Multitasking machining (MTM) systems have become increasingly sophisticated and expensive capital equipment. The lack of practical guidelines for selection of these machines can lead to significant undesirable machine attributes, application mismatch, and longer return on investment. The purpose of this paper is to provide an insight to numerous features and configurations of MTM systems and to present several application‐based selection guidelines.

A taxonomy of MTM systems is developed based on the number of axes of motions, tooling and spindle systems. Practical guidelines for general and advance features are presented with special regard to multi‐axis and multi‐spindle features.

MTM systems are capable of meeting several production goals such as cycle time reduction, minimizing non‐value added times and concurrent processing of multiple parts. However, they possess inherent programming challenges due to their complex configuration and simultaneous machining functions.

The diversity of system configurations demand a decision support system, such as a rule‐based expert system to capture the many variations of MTM systems.

This paper should be useful to decision makers in industry or academia who are involved in selection of MTM systems.

The purpose of this paper is to present a method of rapid prototyping (RP) used in the development of a regenerative pump impeller. RP technology was used to create complex impeller blade profiles for testing as part of a regenerative pump optimisation process. Regenerative pumps are the subject of increased interest in industry.

Ten modified impeller blade profiles, relative to the standard radial configuration, were evaluated with the use of computational fluid dynamics (CFD) and experimental testing. Prototype impellers were needed for experimental validation of the CFD results. The manufacture of the complex blade profiles using conventional milling techniques is a considerable challenge for skilled machinists.

The complexity of the modified blade profiles would normally necessitate the use of expensive computer numerically controlled machining with five‐axis capability. With an impeller less than 75 mm in diameter with a maximum blade thickness of 1.3 mm, a rapid manufacturing technique enabled production of complex blade profiles that are dimensionally accurate and structurally robust enough for testing.

As more advanced RP machines become available in the study in the coming months, e.g. selective laser sintering, the strength of the parts particularly for higher speed testing will improve and the amount of post processing operations will reduce.

This technique offers the possibility to produce components of increased complexity whilst ensuring quality, strength, performance and speed of manufacture.

The ability to manufacture complex blade profiles that are robust enough for testing, in a rapid and cost effective manner is proving essential in the overall design optimisation process for the regenerative pump.