Building a Heater Core
Over the summer I had the opportunity to see why college education exists. I worked second shift on a production line at Denso. For ten hours a day, five to six days a week, I built heater cores in the braze area. I learned that many steps go into one thing and that each step needs to be done exactly how it should be to achieve perfection.
Each station on the assembly line has a matrix check, a second look at what the worker before you performed. This check holds importance! Along with each station having a matrix check, they also have call lights. These lights are used to communicate with the offline worker. All call lights have the three colors, red, yellow, and green. Red and yellow are accompanied with a sound. Red means that you need attention right away and it gives off a continual beeping sound. Yellow means that you need help as soon as they are available and this is paired with a charming bell sound. Green means that everything is OK.
There is a light much like the call light that tells how the line is flowing. Green means the line is moving smoothly, yellow signifies that the line is moving too slow, and red lets the workers know that something is wrong with the machines. When a problem occurs and the line stops, it is the workers job to find something to do and to look busy. This includes cleaning the windows around the machines, sweeping, emptying the trash, etc.
Another thing to keep in mind is change overs (switching the type of core you are working with). When a change over occurs the call light should be turned on to let the offline know to change the robot in order for it to work properly with that part. Once you have the basic rules down you are ready to start building.
The braze area for heater cores consist of four stations. The first station is known as the loading station. To execute the loading station properly you need to be able to follow a rhythm or you will fall behind. First grab a core out of the tote with your right hand and a capsule in your left. Before snapping the capsule on be sure to perform your matrix check. You should be looking at the side of the heater core to make sure there is no tube, fin, or expander damage. If there is, it should stand our right away and you should place the damaged core to the side. If the core seems fine you can now cap the core by lining the capsule up with the core and snapping it on. From there the core is placed on the moving belt to be brought to the robot. The robot then picks the core up, wraps it in wire, clips the extra wire off, and sends it to the unload station.
Keep an eye out for the following problems; Running out of wire (offline should change the barrel) or the robot stops working (maintenance should be called).
The unload station is very similar to the loading station. The only difference is that the core is grabbed off the belt with your left hand and the capsule with your right. The matrix check is the same and if everything looks perfect the core is sent down the belt to the pipe stations. Make sure that you send equal number of cores to the right and left.
The pipe station, unlike the load and unload station, takes a bit longer to get used to. The first step is to grab two pipes, one for each hand, out of the tote. Make sure the circular part of the pipe is connected to your thumb and the oval part is being held by your index finger. Once the pipes fit in your fingers right place them into the jiggys on the robot (they should fit perfectly). Next grab the core off the belt and place it all the way into the robot. Once your hands are taken out the robot will move down to push the pipes firmly onto the core. After the robot stops moving, place two fingers on top of the core, two on the bottom, lift to pull the core out and flip it over to perform the matrix check.
For this matrix check you are looking for two things. One, did the pipe get pushed all the way down and two, is there any light between the capsule and the pipe? If there is a problem with either of these it should be set on a table for inspection by the offline. If both appear to be perfect it can be placed on the flux machine to be sprayed with flux (a white powder that helps prevent leaks that could occur in the core) and heated in the furnace.
The problems that occur at these two stations mainly involve flux. You are out of flux, the flux machine broke, or the nozzle is not spraying any flux on to the core. If any of the previous problems occur, turn the call light on.
At the end of the night each station is responsible for performing their clean-up assignments and signing off on it. The pipe stations are required to sweep the flux by the flux machine, blow the metal scraps out of the robots with an air sprayer, and blow off the conveyor belt of any leftover flux. In charge of emptying all the trash cans and sweeping off the platform is the unload station. The loading station is responsible for emptying the trash by them and emptying the wire scraps into the metal scraps bin. Once everything is cleaned you are free to punch out and leave.
Denso prides themselves in making sure that every worker is as safe as possible. Immediately following safety is the quality of the part being shipped out. Safety rules that each worker should always know is that personal protection gear should always be worn. These include gloves, safety glasses, and sometimes face masks. The face masks are worn mainly when working with flux because, if inhaled, it could cause leukemia. Each worker should also be aware of the signs of passing out (getting cold really fast, sweating abnormally, light headed, dizzy, etc.) If any worker is injured or something happens you should dial 4444. Finally, make sure you are putting out a part that you would want in your car; a heater core that will make the temperature very comfortable when you are driving.
Working at Denso this summer helped me pay for college, allow me to work with others, and have a great hands on experience. Most importantly I realized that I would never want to work in a factory for the rest of my life. College education is important. However, if you ever find yourself looking for a summer job you now know how to build a heater core in the braze area so get to it!