Simple Solutions That Work! Issue 13

DEFECT PREVENTION 23 RICHIE HUMPHREY National Sales Manager THE SCHAEFER GROUP, INC. ARTICLE TAKEAWAYS: • Regular maintenance and documentation of your furnaces is key. • Filter your metal either with a box filter or an inline filter to reduce inclusions • Filtration has many benefits and should be the first thing you look at to correct inclusions and some hydrogen issues. DEFECT PREVENTION WITH A WORLD CLASS MELT SHOP O ne of the best ways to optimize defect prevention is to offer your casting process world-class melt quality. So many companies have lost focus on what is the most important element in the casting process, the quality of melt they have in the dip well . I go into foundries all over the country and see that so many have forgotten how important taking care of the furnaces, fluxing/cleaning the melt and keeping the furnaces sealed are to make a defect-free part. A world-class melt operation has a very low scrap rate at the casting process because of melt quality and reducing oxides due to the care they take in cleaning the melt/holding furnaces. This is the source or “Head of the Stream” where everything else down-stream is a direct result of what comes out of the “Head of the Stream." As I have said so many times, it’s hard to make a good part furnaces are properly cleaned, cleaned on time and skimmed, is far more cost effective than the dollars that are thrown out the door because of high scrap rates and major furnace repairs almost quarterly or on some occasions, monthly. I see this time and again in my travels. Here are a few processes you should be following to make a “World Class Melt Shop." How does your facility compare? 1. How often do you flux and clean your melt furnaces? I cleaned mine every 12 hours. 2. How often do you flux and clean your dip wells/holders? I cleaned mine every 12 hours. 3. How often do you skim your dipwell/at the casting machine? I skimmed mine once per hour. 4. How often do you check the temperature in your dipwells with a handheld “Certified Calibrated Unit” to confirm your thermocouple in your dipwell is reading correctly? I checked 3 times in a 12-hour shift. 5. How often do you check the temperature in your melt furnace with the same hand held unit? I checked 3 times per shift. 6. If you have a manager of the melting operation, how often do they, as manager, go out and take a look at all the furnaces, open the door, look inside to see if they have been cleaned? I looked at least once per day. with bad/dirty metal. So many foundries today have maintenance responsible for the furnaces and they only show up when there is a problem. Foundries don’t regularly check and follow- up to understand if procedures are being followed. I came from a foundry that put the furnaces first and that was easily recognized in the very low scrap rate at the die casting process. All this effort put into the foundation of the process was greatly seen in the bottom line every year when we sat down to crunch numbers. The investment in additional employees that will ensure the Continued on next page