Dust Collector Extends De-Skulling Operation

A thermal lance is a tool used for cutting that uses very high heat in the presence of pressurised oxygen, reaching over 5,000 degrees Fahrenheit. The operator is able to make the cut without having to be directly next to the operation because of the physical length of the thermal lance. Using specialised booths, operators are able to de-skull the bottom of the steel furnace pots. A skull layer accumulates over time and turns into a mixture of slag and iron. Thermal lances are used to cut out the skulls for maintenance and cleaning.

The skull layer cutting operation has to be conducted inside of a booth since the operation produces a dense orange cloud. Considering the size of steel furnaces, slag pots can weigh over 30 tons, meaning using a normal booth enclosure is difficult and time consuming. AAF provided a solution and designed a new booth on rails, giving the end-user the ability to clean the slag pots more easily and effectively.

Challenge

An existing dust collection system was under- performing because it was undersized for the process it was handling. Large amounts of dust particulates were created by  the de-skulling process and overloading the existing dust collection system’s ability to provide adequate ventilation airflow. The system had trouble pulse-cleaning the filters, meaning that the collector could only operate for short periods, causing the operators to take breaks during skull-cutting operations to clean the filters without airflow.

Solution

At AAF’s recommendation, the capture velocity was set higher than the normal range to mitigate the large dust cloud volumes that occur during some instances of operation. An AAF OptiFlo®  cartridge collector designed for heavy dust loading and sized for a larger airflow provided continuous operation for an entire skull cut  process. Additionally, AAF developed a solution, including a movable booth on rails, to speed up the slag pot setup process.

Benefits 

By providing a booth on rails, the operators are able to put slag pots into cutting position faster, reducing downtime for the furnace and total cleaning time. With the addition of the more properly sized OptiFlo® cartridge collector, the dense dust clouds were abated quickly and operated for longer run times.