Welcome to Brainstuff from house stuffworks dot com, where smart happens Him Marshall Brain with today's question, how can water cut through steel? A water jet is a tool used in machine shops to cut metal parts with a very high pressure stream of water. As amazing as it sounds, if you get water flowing fast enough, it can actually cut metal. Think of a water jet is something with about thirty times the pressure of the power washer wand
at your local car wash. Power washing a car washes is an everyday example of a dirt film being cut off the body, wheels, and tires of an automobile. The key to cutting metal with water is to keep the spray coherent. Water jets are able to cut because the spray is channeled through a very narrow jeweled nozzle at a very high pressure to keep the spray coherent. Unlike metal cutters, a water jet never gets dull and it can't overheat. Low pressure water jets were first used for
mining gold in California in eighteen fifty two. Steam and hot water jets were used in the early nineteen hundreds for cleaning. High pressure water jets were used for mining in the nineteen sixties Abrasive water jets were first used in industry in about nineteen eighty. In the past, only one piece of metal could be cut at a time with a saw or other metal cutting mechanical process. It
was time intensive and expensive. Computer controlled water jet and abrasive jet cutting are used today an industry to cut many soft and hard materials. The plain water abrasive mixture leaves the nozzle more than nine miles per hour. The latest machines can cut within two thousands of an inch, and they have jet speeds around mock three. Water jets can cut lots of different things, including marble, granite, metal, plastic, wood, stainless steel, and aluminum. A water jet can cut a
sandwich of different materials up to four inches thick. This odorless, dust free, and relatively heat free process can also cut something as thin as five thousands of an inch. The tiny jet stream permits the first cut to also be the final finished surface of the piece. This single cutting process saves material costs and machining costs. For example, the engineer merely gives a gear drawing to the cutting shop
and gets back the finished gear very quickly. Water jets cut softer materials while abrasive jets are used for harder materials. The actual cutting is often done underwater to reduce splash and noise. Faster feed rates are used to prevent the jet from cutting all the way through the water. Pressure is typically between twenty thousand and fifty five thousand pounds per square inch. The water is forced through a tiny hole in a jewel about one one of an inch
in diameter. For more on this and thousands of other topics, visit how stuff works dot com, and don't forget to check out the brain stuff blog on the how stuff works dot com home page. You can also follow brain stuff on Facebook or Twitter at brain stuff hs W