When planning temporary power requirements for large scale heat treatments, using the experts from your temporary power supplier, along with your heat treatment provider, can yield better overall results for quality, schedule and cost.
Power requirements for heat treatment are driven by three key components:
- Number of kilowatts (kW) required per specific weight of the area of steel to be treated (heat and gradient control band)
- Heating rate per hour (degrees/hr)
- High end set point temperature (soak)
Other factors to consider are heat loss through the insulation being used and any draft effect within the area being heated. Code requires that you block or negate any draft effect in the part being heated, this should be part of the heat treatment written operating procedure.
The most efficient way to negate the draft and reduce total power required for the heat treatment is by utilizing insulation within the internal area of the part being treated. This is assuming access is not restricted and personnel can easily work safely to apply the internal insulation.
When planning temporary power requirements for large scale heat treatments, using the experts from your temporary power supplier, along with your heat treatment provider, can yield better overall results for quality, schedule and cost.
Where internal heating application is the preferred set up method, the same principle would apply for external insulation. Blinding the vessel is a normal safety application before any internal entry is allowed. It also helps restrict draft from systems that are attached through piping or other system pressures as part of the vessel design.
Where larger heat treatments are taking place that require multiple thermal gradient control bands above and below the soak band area and heated band area, thermal dynamics can change significantly due to conduction heat traversing through each control band. Each band effectively helps the other, which, when accounted for properly significantly reduces the overall kW needed.
A heavier density insulation helps to reduce heat loss and aids with temperature retention and control in all areas. The heavier density insulation may have a small financial impact on material cost. This is easily negated by reduced heat loss through the insulation, improved heating, reduced power requirements and fuel consumption having a positive impact on cost and schedule.
When temporary power providers and heat treatment contractors work well together, their success leads to more opportunity. Joint collaboration with reliable providers gives the end users cost, schedule, logistic and sustainable benefits.
For more information, visit axiomht.com or call (714) 655-3205.