Furnace downtime begins with having a reactive state of mind. Ignore the minor problem now, until it becomes a detrimental problem later. Unfortunately, this is a very costly risk to take. This article will explain the 5 reasons you should be proactive when it comes to “hot cleaning” and “cold cleaning” your furnace.
1. Reduce damage to refractory
Corundum is a crystalline form of aluminum oxide and is produced in furnaces from the residual metals after production. The corundum then leaches into the refractory making extraction extremely invasive. As you can see in Figure 2, after extracting the corundum from Figure 1, the refractory walls will need repaired or replaced.
2. Maintain furnace capacity
The buildup will take real estate of your furnace, which means less room for the metal. Less product in the furnace to be melted equals less available metal for production needs, which results in less efficiency and profitability. In the furnace in Figure 1, the production capacity is reduced by the volume of corundum buildup as well as loss of furnace efficiency.
3. Maintain clean metal
Corundum can cause deterioration of the refractory lining, as well as, be a source of metal contamination. The growth can then also lead to higher part rejection rates as the buildup increases.
4. Increase output/production – less downtime
Corundum, as shown above, will pause production over a 7-day period. On average, furnaces that need emergency repairs will need two days to tear out, three days to repair the refractory, and finally a 48-hour period for the furnace to cure and heat up. This process can take even longer if materials cannot be expedited or the detriments are far more advanced than what Fig 1 shows. In addition, residual damage to the electric elements or burners can cause additional down time. Consider that while the furnace is undergoing repairs, it is also not producing, which can cost $20,000-$30,000 a day in lost sales and profits. With less unscheduled downtime you can maximize the production, schedule for regular furnace cleaning, and decrease unscheduled downtime.
5. Save money, make money
Overtime. Downtime. Decreased Output. Three terms that cost a fortune. As the emergency repairs takes time away from production potential, repair costs can also be quite expensive. Depending on the size of your facility, overall, costs can reach $124,000-$174,000, to say nothing of the lost sales potential. Certainly, for facilities that have multiple furnaces this number can rise even quicker.
Clean your furnace! Scraping the walls with specialized rakes and fluxing every shift will decrease any risk of furnace downtime and costly repairs. The corundum formation occurs from lack of cleaning, or not on a regular basis. It is critical to be cleaning the furnaces after every shift, otherwise known as, hot cleaning, however, also schedule “cold cleaning” practices biannually.
Hot and Cold
Although a difficult job due to the extremely hot environment and physical challenge, hot cleaning practices are a major part of the fix, and require in-house training of your team (proper practices, tools and management insistence). Cold cleaning can be supported by the Onex team, providing professional, efficient and proper cleaning and material repairs, all in a timely fashion.