Search Results for machine control

Most filament winding machines now have computer controls and at least three axes. Winding with four axes is increasingly common because the shapes of the products have evolved to include more complexity. The automation used on the winding machine and ancillary components does not eliminate the need for proper fiber handling. This chapter is a primer on modern filament winding equipment and its use, starting with an overview of machine control and then discussing the design and structural analysis of filament wound components such as pressure vessels, pipes, grid structures, deep sea oil platform drill risers, high-speed rotors, and filament-wound preforms.

This chapter discusses the ways in which the evolution of filament winding software systems has capitalized on the inherent flexibility of computer numerical controlled winding machines and enhanced their productivity. It provides a detailed discussion on different types of geometries that can be wound, from the simple to the highly complex, with insight into the limitations, advantages, and challenges of each. Components covered include classic axisymmetric parts (rings, pipes, driveshafts, pipe reducers, tapered shafts, closed-end pressure vessels, and storage tanks), nonround sections (aeromasts, airfoils, box sections, and fuselage sections), curved-axis parts (elbows, ducts), and special applications (tees). Basic winding concepts, such as band pattern, are discussed and explained, and some simple predictive formulae are introduced. The chapter also provides examples of programming various geometries using advanced software tools and discusses how various materials, such as rovings, tow-preg, prepreg tape, and woven materials, affect winding program generation.

The inspection of castings normally involves checking for shape and dimensions, coupled with aided and unaided visual inspection for external discontinuities and surface quality. This chapter discusses methods for determining surface quality, internal discontinuities, and dimensional inspection. Casting defects including porosity, oxide films, inclusions, hot tears, metal penetration, and surface defects are reviewed. Liquid penetrant inspection, magnetic particle inspection, eddy current inspection, radiographic inspection, ultrasonic inspection, and leak testing for castings are discussed. The chapter provides information on the procedures involved in the inspection of castings that are limited to visual and dimensional inspections, weight testing, and hardness testing. It also discusses the use of computer equipment in foundry inspection operations.

The low-pressure permanent molding (LPPM) and semipermanent molding (LPSPM) processes are versatile, and they meet the quality requirements of a variety of high-integrity, large-sized, and thin-walled aluminum castings for various industries. This chapter presents the major features, operation sequence, advantages, and applications of LPPM, LPSPM, and counter-pressure casting.

The coordinate measuring machine (CMM) is used for three-dimensional inspection of both in-process and finished parts. This chapter provides a detailed account of the operating principles, measurement techniques, capabilities, and applications of CMMs. The types of CMMs are described. Vertical CMMs include cantilever-type, bridge-type, and gantry CMMs; horizontal CMMs, such as the horizontal-arm type, are also covered. The CMM application for geometric measurement, contour measurement, and specialized surface measurement are discussed.

This chapter reviews the development of filament winding systems and the automated processes used in state-of-the-art filament winding facilities. It first provides a description on the early stages of modern filament winding, followed by brief information on the advances of filament winding in the computer age. Then, the chapter discusses the requirements for filament winding in manufacturing oil and gas industry components and in high-volume production of sporting goods, propane tanks, and curing ovens. The chapter concludes with examples of the versatility of filament winding in producing complex parts.

This chapter reviews the current technology and examines force application systems, force measurement, strain measurement, important instrument considerations, gripping of test specimens, test diagnostics, and the use of computers for gathering and reducing data. The influence of the machine stiffness on the test results is also described, along with a general assessment of test accuracy, precision, and repeatability of modern equipment. The chapter discusses various types of testing machines and their operations. Emphasis is placed on strain-sensing equipment. The chapter briefly describes load condition factors, such as strain rate, machine rigidity, and various testing modes by load control, speed control, strain control, and strain-rate control. It provides a description of environmental chambers for testing and discusses the processes involved in the force verification of universal testing machines. Specimen geometries and standard tensile tests are also described.

Machine vision is a means of simulating the image recognition and analysis capabilities of the human eye/brain system with electronic and electromechanical techniques. This chapter discusses four basic steps in the machine vision process, namely image formation, image preprocessing, image analysis, and image interpretation. Details of the processes involved, equipment used, and the factors to be considered are also presented. In addition, the applications of machine vision are discussed.

Molding flasks and other supplementary equipment are essential for molding complex shapes at competitive production rates and costs. This chapter addresses the design aspects of molding flasks and accessories, the features and handling accessories of molding machines, core making machines and innovations for productivity and quality, and automated core-setting aids.

This chapter covers the practical aspects of machining, particularly for turning, milling, drilling, and grinding operations. It begins with a discussion on machinability and its impact on quality and cost. It then describes the dimensional and surface finish tolerances that can be achieved through conventional machining methods, the mechanics of chip formation, the factors that affect tool wear, the selection and use of cutting fluids, and the determination of machining parameters based on force and power requirements. It also includes information on nontraditional machining processes such as electrical discharge, abrasive jet, and hydrodynamic machining, laser and electron beam machining, ultrasonic impact grinding, and electrical discharge wire cutting.

The gravity permanent mold (GPM) process produces castings of high strength and integrity with good surface finish and consistent dimensions. This chapter lists castings produced using GPM and semipermanent mold (SPM). It illustrates the basic elements of a conventional tilt pour machine. The chapter also provides an overview of the high-volume rotary table, high-volume production rotary manufacturing cell, cycle time planning, sizes of tilt pour machine and table, and improvement of turntable uptime. It also presents some of the common semipermanent molded castings.

This chapter details low-temperature test procedures and equipment. It discusses the role temperature plays in the properties of typical engineering materials. The effect that lowering the temperature of a solid has on the mechanical properties of a material is summarized for three principal groups of engineering materials: metals, ceramics, and polymers (including fiber-reinforced polymers). The chapter describes the factors that influence the selection of tensile testing procedures for low-temperature evaluation, along with a comparison of tensile and compression tests. It covers the parameters and standards related to low-temperature tensile testing. The chapter discusses the factors involved in controlling test temperature. Finally, the chapter discusses the safety issues concerning the use of cooled methanol, liquid-nitrogen, and liquid helium.