- 18 minutes ago
Curious minds find out how things like chemical tank pressure vents, candy wafers, food trucks and traditional ropes are manufactured.
了解化工储罐压力排气阀、糖果片、餐车以及传统绳索的制造过程
了解化工储罐压力排气阀、糖果片、餐车以及传统绳索的制造过程
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00:22Today on How It's Made,
00:25Chemical Tank Pressure Vents
00:31Candy Wafers
00:37Food Trucks
00:43And Traditional Ropes
00:54It's common for pressure to build up inside
00:56Chemical Tanker Trucks during transport.
01:02Special Vents regulate that pressure,
01:04preventing any unwanted gas buildup which could lead to an explosion.
01:15Pressure relief vents are standard equipment on chemical tanker trucks.
01:22They ensure tanks can hold up to the pressures inherent to this industry.
01:28Production starts with a bin of wax pellets.
01:32They use pellets to make models of the vents parts, in a process called lost wax casting.
01:41Pellets are fed into an injection machine.
01:43The wax melts into a mold of the vents lower housing.
01:52Four wax models are fused to a single wax tree stand.
01:58The tree stand is left to cure for a couple of hours.
02:01Once cured, a worker dips the wax tree into a slurry of ceramic.
02:12He removes the stand of wax models, then twirls it to drain any excess ceramic.
02:19This is the first of several ceramic coatings.
02:24Between coatings, he applies silica sand to the wet ceramic.
02:29The sand rains down onto the ceramic, creating a stucco effect.
02:36The first layer of stucco is finely granulated.
02:39The next few layers will be coarse.
02:44By building up progressively coarser layers of stucco, he creates a ceramic shell with the
02:50desired thickness and strength.
02:56The final layer of sand is very coarse.
03:00Air pumps through the sand as the worker dunks the models.
03:03This process ensures uniform coverage of the heavier sand.
03:10They bake the forms next, melting out the wax and hardening the ceramic into shells.
03:18Next, a team pours liquid steel into a ladle.
03:21The ceramic shells have been heated to around 3,000 degrees in an oven.
03:26Workers pour hot liquid steel into the hollow tree.
03:33They add a chemical sealer, then top the molten metal with a piece of ceramic fiber insulation.
03:51After about three hours in an oven, the steel castings are solid.
03:55A worker shatters the ceramic, revealing the vent housing parts.
04:01A powerful circular saw slices the parts off the tree.
04:07Workers clean off any ceramic residue.
04:12Computer guided tools calibrate the pressure vent housing part to precise specifications.
04:23After cleaning and polishing, the part is complete.
04:26It's time for assembly.
04:29The worker starts with the top of the pressure vent.
04:32A large spring is inserted to aid pressure relief.
04:36A metal plate is added to seal the top of the vent to the lower part.
04:41The lower vent housing is then seated on the metal plate.
04:46He moves the assembly under a hydraulic ram.
04:49The ram presses the lower housing, the sealer plate, and the spring to a specific tension.
04:55He then screws the lower housing to the top of the vent.
05:00A metal ring inscribed with the vent's model and flow rate is attached at the top.
05:12This chemical tank pressure vent is now ready for testing.
05:17The technician screws it to the test stand.
05:22He activates a system that forces compressed air into the vent.
05:26This confirms whether the vent works at the desired setting.
05:31Once approved, he attaches a cover to shield the vent from rain and snow.
05:38The trackable serial number is etched into the top using a laser.
05:49This vent is now ready to prevent hazardous situations.
06:07The candy wafer is a classic American treat.
06:12Invented in 1847, it's a thin, lightweight disc of sugary candy.
06:18It's softer and dissolves faster than hard candy.
06:22You can bite into it right away or let it melt in your mouth.
06:27These candy wafers come in eight different flavors.
06:31The original roll has a random assortment of 38 pieces.
06:35Part of the fun is seeing how many of your favorite flavors you get.
06:40This factory makes one flavor at a time.
06:43The first step is to add food coloring and flavoring to pulverized sugar.
06:49This pink color and mint flavoring produces a wintergreen taste.
06:56Corn syrup comes next, along with a binding solution of vegetable gums and gelatin dissolved in water.
07:04After mixing for about eight minutes, the candy dough's consistency is checked.
07:10If it isn't thick, elastic or sticky enough, more binding solution is added until the dough is just right.
07:19Workers divide the dough into chunks, then feed them into a dough sheeter.
07:24This is the first station on the wafer forming line.
07:27The black dough is licorice flavored.
07:29The conveyor returns leftover dough from the end of the line to be reused for making new wafers.
07:35The dough sheeter compresses the chunks and leftovers.
07:39They're pushed through a slot forming a dough sheet that's 20 inches wide by about an inch thick.
07:45This yellow dough is lemon flavored.
07:53A steady sprinkle of corn starch prevents the sheet from sticking to the equipment.
08:00Rollers compress and stretch the dough forward, flattening the sheet to an inch thick.
08:06The next station stamps on the company logo, then cuts out the wafers.
08:11The cutter moves up and down 180 times per minute.
08:16The wafers fall through a gap to a moving conveyor belt below.
08:24The conveyor belt moves the wafers to a multi-level tunnel dryer.
08:34They pass through the dryer 13 times over the course of an hour.
08:45These green wafers are lime flavored.
08:48The dryer temperature is about 150 degrees Fahrenheit.
08:52Warm enough to remove half of the moisture without melting the sugar.
08:57These brown wafers are chocolate flavored.
09:01Once out of the dryer, the wafers pile up in trays without sticking.
09:08Workers stack the trays in a drying room.
09:11It's heated and humidified with steam.
09:15The candy wafers stay here until their moisture level drops to between 0.75 and 1%.
09:25The factory tests a few samples using a device called a penetrometer.
09:29It measures the force required to penetrate the candy wafer to the point of breaking it.
09:36This ensures the candies are the correct consistency.
09:41When the trays come out of the drying room, workers send the candies to the packaging line.
09:49The colors are mixed together, ensuring every roll of candy has a random assortment of flavors.
09:57The wafers flow into channels, which stand them on their sides.
10:05Workers grab about two rolls worth, then fill two channels of a feeder that takes them to the wrapping station.
10:15Another worker fills in the gaps, ensuring each roll has 38 pieces.
10:21The wrapping machine cuts printed, translucent paper wrapping and applies a bead of glue to one edge.
10:28In a matter of seconds, the machine lifts the roll into the wrapper, seals the edges, and twists the ends
10:35closed.
10:35As the sealed rolls move on a conveyor belt, heated blocks iron the twisted ends flat.
10:43Each candy wafer roll weighs 2 ounces.
10:46Workers pack 24 rolls per retail box, then pack the boxes in shipping cases.
10:54In addition to a traditional roll with assorted flavors, the factory also produces chocolate-only rolls.
11:00Production has modernized over the years, but the recipe itself hasn't changed much since the first candy wafer rolled off
11:08the production line in 1847.
11:23Food trucks used to only sell sandwiches and other prepackaged food.
11:27Not anymore.
11:28The modern food truck is a mobile restaurant with a full kitchen inside.
11:34Food is cooked fresh and sold to customers through a service window.
11:43Most food trucks are standard panel trucks.
11:46Their cargo area is a fully equipped commercial kitchen with a service window on one side.
11:55They're usually customized by boutique companies, so there's no standard method.
12:02However, certain modifications to the panel trucks are common, like enhancing the truck's suspension system,
12:08or reinforcing the flooring and walls to support the kitchen's weight.
12:13To lighten the load, this company builds the kitchen's structural components out of aluminum bars, rather than heavy steel.
12:24Once the pieces are cut, a worker assembles, then welds them together.
12:31This structure will support a stainless steel countertop.
12:42Workers cut the countertops and cabinets from thick sheets of stainless steel.
12:51They bend the sheets using a machine called a press brake.
13:01For this countertop, they bend a 90-degree angle on the front end to form a 1.5-inch square
13:07edge.
13:10To construct walls and ceilings, they rivet thin sheets of stainless steel or aluminum to panels of wood.
13:19Fire retardant plywood is used for the kitchens.
13:22The boards are installed over styrofoam insulation.
13:27They leave the truck's aluminum floor as is.
13:31Once the walls, ceiling, and flooring are complete, it's time to install the kitchen's cabinets and counters.
13:40Workers screw each counter support to the wooden structure of the wall.
13:45Then fasten the countertop with rivets.
13:55They peel off the film that was protecting the stainless steel surface.
14:02Next, they install the major appliances, which include a commercial refrigerator, freezer and cooking equipment.
14:12Then, the electrical box is installed.
14:15They connect wiring for the outlets, lighting, water heater, water pump, and air conditioning system.
14:28The generator is installed underneath the nearest counter.
14:32It supplies the truck with electricity.
14:35Next to the electrical box is the power transfer box.
14:38It contains a switch that enables the truck to use an outdoor power source.
14:43The switches for the interior and exterior lighting are underneath the electrical box.
14:55Workers install the light fixtures, cabinetry, sink, and serving window.
15:03They also install the gas lines that power the commercial cooking equipment.
15:09This truck has several gas appliances.
15:12A six burner gas range with large oven, a deep fryer, a charcoal grill, and a flat top cooking surface.
15:22The kitchen is equipped with a ventilation hood over the cooking area.
15:27Its powerful fan gathers smoke and sends it out a vent on top of the truck.
15:33It's time to outfit the exterior.
15:40Some food trucks are painted, but most use graphics that are digitally printed on adhesive vinyl.
15:50After positioning each panel of the design, they apply heat with a torch.
15:56This removes trapped air, stretching the vinyl over rivets and other protrusions.
16:08This mobile eatery is ready to roll with a kitchen that meets fire code and food service regulations.
16:18It may not provide the ambience of a sit-down restaurant, but when a food truck pulls up, you never
16:23need a reservation.
16:38Rope has been made out of plant fibers for centuries.
16:42Stronger synthetic and steel cords are available, but they're still a market for traditional twine.
16:48They have their own unique strengths, and that's why we are still bound by their ties.
16:58Woven from manila, sisal or flax fibers, traditional ropes are a binding element in our world.
17:06They're easier to grip and stretch less than synthetics.
17:12At this deep and narrow building, they've been twisting fibers into rope for more than two centuries.
17:19They're still producing rope the old-fashioned way.
17:22The process starts with racks of natural fiber yarns.
17:27The yarns are funneled through separators, which configure them to twist evenly together.
17:32The fibers then travel through tubes that squeeze them into bundles.
17:38Workers tie the ends of the bundles onto a wheeled vehicle called the forming machine.
17:44They roll the machine back until there's no slack in the bundles.
17:50The machine is then sent to the opposite end of the factory, over 1,000 feet away.
17:58As the machine travels backwards, its gears turn hooks, twisting the yarns into a tight configuration.
18:06The formation of the twists ensure an even distribution of tension.
18:10This is what makes rope so strong.
18:15This long indoor space is called a rope walk.
18:18There aren't many of them left in the world.
18:24Halfway down, a worker places a trestle underneath the twisting yarns.
18:30This keeps them off the floor and prevents tangling.
18:35When the machine reaches the back wall, it stops and workers cut both ends of the strands.
18:44They tie them to posts to maintain tension and prevent unraveling.
18:54The twisted fibers stretch from one end of the building to the other.
19:03On one side, they tie three of the strands to a machine that will transform them into a rope.
19:15Halfway down, they bring in a cart that holds a piece of grooved wood known as a top.
19:22They tuck the twisted strands into the grooves of the top.
19:30They then roll the cart down to face the rope making machine.
19:35A worker ties rope around the strands in the top.
19:40This holds them in place as the rope making machine twists the three strands into one.
19:48The cart rolls along rails propelled by twisting action.
19:57It leaves newly formed rope in its wake.
20:01The rope machine with twisting hooks remains in the same place.
20:08When the cart arrives at the opposite side of the building, the rope is formed.
20:13A worker removes the ties around the top.
20:17They now have a piece of rope that's over 700 feet long and almost 5 inches in diameter.
20:27They slice the rope at both ends.
20:34Then they wind it onto a big spool, packing it into a tight coil.
20:39This traditional rope is almost ready to be shipped.
20:45The customer requested looped ends for securing the rope with a shackle.
20:52So the rope maker unravels the ends and pierces the rope with a hollow tool called a fid.
21:00He makes a loop and slides the unraveled strands through the fid.
21:05He finishes the job by weaving the strands into the rope.
21:12They're ready to test a segment of the rope.
21:16Two hydraulic jaws pull it until it breaks.
21:19The rope must be able to handle 55 tons of force.
21:29Traditional ropes have the strength to carry on, as they have done for a very long time.
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