History of the Screw
We do not know who first designed the screw. There is historical evidence that by the first century it was used in a screw press. Screw presses used by the Romans to squeeze olives for oil and grapes for wine have been found. Archytas of Tarrentum is credited by the Greeks with the invention of the first screw. But the Greek philosopher Archimedes is also credited with inventing the screw around 234 BC. … Read more
History of the Screw
Manufacturers are on the brink of a major leap in production. Industry 4.0 describes the current generation of workflow processes infusing smart technology, big data and brainpower. According to the National Institute of Standards and Technology (NIST), “ [M]anufacturers that successfully implement the Industry 4.0 technologies best-suited for their businesses no longer need to choose between focusing on a better top line or a more profitable bottom line – as they can improve both at the same time.”
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Wear characteristics of one plastic against another vary widely, even among those materials with good natural lubricity. When an application calls for plastic-to-plastic bearings, shafts, gears and other parts, the combination must be chosen carefully.
Because plastics are not rigid bodies, they do not behave according the natural laws of friction. It is these deviations which cause some of the unexpected results when plastics are run against metal. Frictional forces are not proportional to load, friction increases with increasing speed and the static coefficient of friction is lower than the dynamic. … Read more
Ever watched “The Jetsons”? It was a ‘60s cartoon family living in the future. George Jetson drove a gas-free hovercraft. Jane, his wife, and the school-age children chatted on mobile and video calls. The family also had a spunky robotic maid, Rosie, who cleaned and maneuvered around a talking dog, Astro.
Today we live like the Jetsons. We see gas-free electric cars on the road. We rely on the internet for everyday activities. Perhaps you’re reading this blog on a mobile phone. … Read more
Generally, there are four commonly used thermal properties of plastics: Heat Deflection Temperature, Continuous Service Temperature, Melting Point or for some, Glass Transition Temperature (Tg) and Coefficient of Thermal Expansion.
Heat Deflection Temperature (ASTM D648)
Heat Deflection Temperature or heat distortion temperature (HDT) is the temperature at which a polymer deforms to heating or cooling under a specified load. ASTM stands for the American Society for Testing and Materials which is an international society that develops and publishes voluntary technical standards for materials among other things. … Read more