Make a frame with insulation and place it on the object to be heated to improve the heating efficiency.
The heating target of frame heating is heated with three elements.
1. Direct heating from heat source
2. Reflective heating from the wall,
3. Radiant heating which is heated by the reflected light and radiated from there
Preventing adverse effects of updraft
In open heating, the air around the object to be heated is also heated and thermally expanded and lightened, so an updraft is generated.
Air at normal temperature and normal pressure flows into the space that has become lean and low pressure due to the updraft.
This inflowing air is not good for heating work because it contacts and cools the heating object.
Frame heating does not generate a flow of cooling air, creating an effective heating environment.
It can also be used as a masking material for parts of the insulation that you do not want to heat.
Since this frame itself becomes hot when used continuously, its effectiveness as a masking material decreases.
Forced cooling is required for continuous use.
Verification of rereflection heating method-Difference between flat surface heating and frame heating
If inert gas is flowed into the frame, oxidation-free or low-oxidation processing can be performed.
Covering the top of the frame with quartz glass will make it more perfect.
Comparison of open heating and frame heating
Related page:
6-3.Re-reflective heating method – Groove heating 
6-5.Re-reflective heating method – Dome heating 
6-1.About Re-reflective Heating Method 
6-6.Re-reflective heating method – Box heating 
6-2.Re-reflective heating method – Large condense mirror 
Verification of rereflection heating method-Difference between flat surface heating and frame heating 
Verification of rereflection heating method-Difference between flat surface heating and groove heating 
5-4.Proper use of near-infrared heating and far-infrared heating