Residential Water Heaters Air Bags Jelly Beans Ice Resurfacers
Today on "how it's made"... Residential water heaters... Air bags... Jelly beans... And ice resurfacers. The residential water heater was invented back in 1889, and the basic concept still applies today. It heats water, usually with natural gas, propane, or electricity, then keeps it continuously hot so that you always have a supply ready for the bathroom, kitchen, or anywhere else you need it. Water heaters may look plain, but there's a lot going on inside. To make one, a hydraulic press transforms a round, steel blank into a dome shape. This dome will form the base of a gas-heated tank, and it will hold the burner. Next, rollers behind and above curl a sheet of steel around a cylinder. This forms the inner-tank shape. A seam-welder device then pinches the two ends of the tank shape together and welds them. In the next step, a worker positions the tank body under a projection-welder. He selects a threaded fitting, places it on the tank, and lowers the welder. This projection-welder uses 10,000 volts of electricity to fuse fittings to the tank body. It also welds fittings to the top of the tank. Valves and other parts will be screwed into these fittings later. Next, a press applies over 27 tons of force to fit a top onto the tank. Then they spray liquid enamel inside of the spinning tank. It will be baked in at 1,650 fahrenheit for 45 minutes to prevent rusting. Now it's back to the bottom of the tank. A worker inserts a flue tube in a hole in the center, and an automated welder joins it to the tank base. The flue will vent gases from the burner. After anti-rust enamel coating is baked onto the base and flue, they lower the tank body onto it. Next, robotic welding arms work both ends of the tank. One welds the base to it, the other bonds the flue to the top. Now the pressure test. They pump air into the tank and then pour water over the outside. If water bubbles on the tank, it means air is escaping and there's a leak that needs to be fixed. Here they install elements in an electric water heater... And they hook up a thermostat and the wires that run to it. Now it's time to make the tank's outer shell, or jacket. An operator slides a painted-steel shape onto a mandrel so that it becomes cylindrical. A lockformer then moves along a rail, folding and pressing the seam together. Next, a rollformer crimps the top and bottom edges so that lids can be easily installed. Here they drape a plastic apron over a tank... And then slide on its jacket, or tank shell, with just the electric components exposed. They screw a steel cover over them. Here's a demonstration of what's next. A chemical reaction causes polyurethane foam to expand in seconds. They inject this expanding foam into the plastic apron that's now between the tank and outer shell. The foam will insulate the tank. Now they finish installing the wiring on this electric heater... And then do an inspection. It makes the grade. On gas heaters, they slide a burner into the dome-shaped base and then connect the burner tubes to the gas valve. They attach some wiring that controls the burner ignition... And then hook it up to the gas line for a test run. That inner glow is the burner at work. They light a torch on the flame and pass it over the valve to check for little gas leaks. It didn't ignite, so there aren't any. It gets the seal of approval, and now it's up to the consumer to test the water when it's installed. The air bag was invented in the 1960s, but it actually didn't catch on until several years later. By the 1980s, automakers were installing them in most vehicles. Air bags deploy when sensors detect a sudden deceleration and inflate them, giving vehicle occupants the protection they need. This side-curtain air bag inflates in less than . 020 of a second. Blink, and you'll miss it. Air bags don't have any seams because they're woven in one piece. Big, computerized looms weave at a blurring speed-- 600 revolutions per minute. They're called air-jet lacquered looms. They lift and lower each nylon yarn to make an intricate one-piece fabric. Up to 10,700 yarns could be used to make the material. If even one of the thousands of yarns break, an electrical sensor will detect it and shut the loom down. It's a step to ensure quality control. Despite this rapid weaving action, the loom produces just over 26 feet of fabric an hour. That's because it's very dense fabric. That density will allow the air bag to stand up to the force of deployment. Now the woven fabric goes through an inspection station. As automated rollers wind it up, a worker examines it. If it's acceptable, he signs it off. Next, it's on to the scouring station. Here a machine unwinds the air-bag fabric as rollers guide it towards a wash-and-dry system that's 118 feet long. The rollers draw the air-bag material through a number of big wash tanks to ensure a thorough cleaning. Then a series of hot rollers dry and press the fabric. The freshly laundered air-bag material moves through the coating machine. A hose pumps liquid silicone onto the fabric, and a scraper overhead distributes it. As a worker scoops some up, you can see that it's as thick as molasses. The silicone seals the air-bag fabric. But it's wet and sticky and needs to dry, so it passes through a series of ovens heated to about 370 degrees fahrenheit. As it dries, the silicone cures to the fabric. Now a computer-guided laser cuts the material with the precision and speed that no human could ever replicate. Black lines woven into the fabric assist the laser as it cuts the air-bag design. At any point in time, it's cutting multiple air bags out of the fabric. When the job is done, the conveyor belt moves the air bags forward. And now they're scrutinized by humans. A worker pulls the one-piece air bag across a template and examines it to make sure the dimensions match. Then it's sent over to the sewing station. Although the air bags have been seamlessly woven, attachment and reinforcements still need to sewn on. The stitching is computer-controlled. A worker feeds the fabric to the sewing machine and then simply presses a button. The machine stitches together the tabs that will connect the air bag to the inside of the vehicle frame just above the side window. Here it sews a tether onto the bag. This strip of fabric will also be used to hold the air bag in place. Now it's time to test a sample air bag from the production run. And, yes, it works perfectly. The jelly bean is a colorful treat. But, unfortunately, no one is sure exactly when the jelly bean was invented or how. It's believed that the jelly center dates back to biblical times as a candy called turkish delight. Many centuries later, the outer shell was added, thus making the jelly bean we know today. The jelly bean is very popular. Billions are sold at easter alone. To make jelly beans, they heat liquid sugar in a big kettle to 347 degrees fahrenheit. They add glucose, which is a more concentrated sugar, and then starch. An agitating device mixes it all together... While elsewhere in the factory, starch spills out of a drum onto big trays. A leveler moves back and forth to even out the starch on the trays. The trays then move forward, and a brush knocks off the excess starch. It will be recycled. A molding board now presses down into the starch. It makes 756 jelly-bean impressions in the starch in each tray. The impressions in the starch will serve as molds for the jelly-bean centers. Nozzles inject the sugar-and-starch mix cooked in the kettle into the starch molds. This system can make almost a million jelly-bean centers an hour. Next, the conveyor belt takes the jelly-bean centers to the drying room, where they stay for 24 hours. This solidifies them. They become chewier. Arms flip the trays of dried candy centers in starch and dump them into a big drum that will separate them. When the trays flip back, they're refilled with starch, and the molding process begins again. Meanwhile, the dried jelly-bean centers, now separated from the starch, tumble out of the drum onto a wire-mesh conveyor system. It transports them to a steam belt, which dampens them. This readies them for the next step-- sugarcoating. The jelly-bean centers go into a sander drum that tosses them around while nozzles spray them with sugar. In another part of the factory, liquid sugar flows out of a kettle into a tub. A worker adds blue food coloring to the syrup, and then he blends it in. This mix is called engrossing syrup. He adds the engrossing syrup, along with some flavoring, to the jelly-bean centers as they tumble around in a tilted, spinning pan. After they turn a very sticky blue, the worker dumps some sugar into the pan. This process is repeated four times in order to build up a coating around the gummy center. The next day, when the beans have hardened, they add hot syrup to the mix and toss the beans around again. This polishes the jelly beans. There's a lot of sweet stuff here-- 124,000 jelly beans in each pan. Now he adds a little wax. And as the pan spins, the beans rub against each other, distributing the wax. This adds gloss to the polish. Then the pan stops spinning, and the jelly beans air dry for 24 hours to allow the glaze to set. It's the finishing touch. After 3 1/2 days, this big batch of jelly beans is ready. They move in a multi-colored mass along a series of conveyors. They fall into a scale system that portions them out for specific bag sizes. Then a trap door opens, and they drop down a chute to the packaging department. Once they're in the bag, the jelly beans are ready to sweeten your day. In just minutes, an ice resurfacer can smooth the surface of an ice-skating or hockey rink. Before it was invented in 1949, it took several workers over an hour to resurface the ice using scrapers, squeegees, and hoses. Today, these machines provide quick, uniform results. If you ice-skate, you're thankful for this machine. It smooths the ice in just a few turns around the rink. To make an ice resurfacer, they weld together steel pieces to build the mainframe. The frame has to be very strong because it will support everything from the engine to the water tank. It's a load of almost 3 tons. Sparks fly as they grind smooth the areas where parts will be mounted. The sparks are actually steel fragments being sanded off. Next, they weld support braces with holes in them to the center of the water tank. These are called baffles, and the holes will allow the water to flow into both ends of the tank. Now they slide a piece of spiraling steel, which is auger flighting, on one end of a pipe. And they slip a piece that twists in the opposite direction on the other end of it. They weld a u-shaped paddle to the pipe between the two steel spirals, or flightings. The paddle is a critical part. The flightings will feed ice shavings to it, and the paddle will then toss them to a bin mounted above a water tank to be disposed of later. Next, the worker clamps the flighting to a hydraulic cylinder. He turns a lever, and hydraulic energy pulls the clamp, drawing the auger flighting snugly to the pipe. As the clamp holds the flighting in position, he welds it to the pipe. Now they're solidly sealed together. Next, another worker places a long steel blade on a magnetic table. The magnets hold it down while a grinding machine moves over it, sharpening the edge. Because the grinding generates heat, the machine also floods the blade with water. This cools it down so the steel stays hard. Now, using a crane, they lower an engine onto the frame that we saw welded together earlier. Then they slide the rear drive shaft into place and bolt it down using a pneumatic wrench. The tires for an ice resurfacer will need some serious traction. Each tire gets 92 of these metal studs. They drop the studs into a revolving feeder. The studs funnel down a tube to the stud gun, ensuring that it never runs out of ammunition. The road these tires travel will be nothing but a sheet of ice, and these studs should allow them to stay the course. Next, using a crane, they transfer the water tank to the center of the frame. The snow bin, which will hold the scraped ice, is next. They place it on pivot points at the front. Then workers slide the blade into place. The bolt it tightly, working from the center outward. The workers are shielded from the very sharp blade by a plastic sleeve that sheathes the edge. When the blade is secure, they remove the plastic. Now it's time to give the ice resurfacer a test run. The steel flightings twist towards the paddle at the center, as they should. Here's a close-up of that razor-sharp blade that will shave the ice. A rectangular scraper slides over the flightings, preventing snow from building up and clogging the system. This ice resurfacer is now ready for the rink, and it's sure to smooth the ice for years to come.