This chapter provides guidelines on how to set up and run an effective quality-improvement program for aluminum extrusion operations. It begins by identifying production processes and variables that impact the quality of hard and soft alloy extrusions. It then presents a series of checklists and flowcharts that can be used to monitor and troubleshoot billet-making and extrusion processes, die construction, equipment maintenance, heat treating, and sawing and stretching procedures. It also discusses the importance of charting test results and monitoring surface treatments that may be required to improve corrosion, oxidation, or wear resistance.

Coal-based thermal power plants play a major role in the welfare of many nations and the overall global economy. This chapter describes the basic equipment requirements and operating principles of thermal power plants, particularly subcritical, supercritical, and ultra-supercritical types.

A turbine in a fertilizer plant began to vibrate and was shut down to investigate the problem. A first stage rotor blade was found fractured and was removed along with several other blades for further examination. Based on their observations and testing, investigators concluded that the blade cracked at the tenon due to high hardness of the base material. Vibration caused the crack to grow, leading to final failure by fatigue.

A generating system in a hydroelectric power plant was shut down to investigate an abnormal sound coming from one of the turbines. A piece of metal that had broken off one of the vanes on the runner was found in the tail race and was subsequently examined along with the runner. Based on the fracture characteristics, as described in the report, the vane failed in fatigue due to a crack that initiated in an area of stress concentration.

This report describes the failure of a gas turbine in a combined-cycle power plant and the examination and tests that were conducted to determine the cause. Based on microstructural analysis, hardness measurements, and tensile tests, the failure was attributed to inadequate clearances in the seal land region between two stages in the compressor section of the rotor. The report also recommends changes to remediate the problem.