A heating or welding fixture that distorts under temperature ruins the part it is supposed to hold. Graphite fixtures resist heat, but distortion creeps in when the grade, geometry and support are wrong. This article covers six specs that keep a fixture flat and stable through repeated heating.
Jiecheng Graphite (since 2003) machines heating and welding fixtures to spec, and confirms grade and flatness in writing.
Six specs that stop distortion
Grade sets thermal behaviour and creep resistance. Wall thickness carries the load. The pocket design allows controlled expansion. Support points prevent sag. Flatness on the datum controls the finished part. And the inspection report catches drift before it reaches your line.
· Grade matched to the operating temperature
· Wall thickness sized to the load
· Pocket design that allows expansion
· Support points that prevent sag
· Flatness held on the datum face
· Inspection report per batch
Where heating fixtures are used
Welding, brazing, soldering and heating fixtures all face the same enemy — distortion. The difference is the temperature and the cycle, so the spec must match your process, not a generic fixture.
· Resistance and induction heating fixtures
· Welding and brazing holding jigs
· Heat-treat fixtures and shields
· Soldering and reflow carriers
What to specify before you buy
Give the supplier the temperature, load, pocket geometry and flatness requirement. Jiecheng Graphite machines these fixtures in its 3,000 m² plant and ships worldwide.
Spec | What to confirm | Why it matters |
Grade | Temp limit | Sets stability |
Wall | Load size | Stops sagging |
Pocket | Expansion gap | Allows growth |
Support | Point layout | Prevents warp |
Flatness | Datum value | Controls part |
Buying checklist
1. Send temperature, load and process details
2. Confirm pocket and expansion design
3. Specify flatness on the datum face
4. Agree grade and inspection report
5. Freeze the spec for repeat orders
FAQ
Why does my fixture warp?
Usually grade, load or support. Match grade and add support points.
Can fixtures handle repeated cycles?
Yes, with a grade rated for the temperature and proper design.
Do I need a drawing?
A drawing or sketch is best; it removes guesswork from grade and fit.
Working with a fixture supplier
A fixture is only useful if it matches your furnace and cycle. Send the temperature, load and datum requirement, and let the supplier confirm the design. Jiecheng Graphite machines fixtures against your process data and holds the geometry, so the first part and the tenth part sit the same way.
· Send process temperature and cycle
· Confirm the datum and load
· Keep the drawing on file
Distortion is preventable. Fix the grade, wall, pocket, support and flatness, and the fixture stays accurate. Jiecheng Graphite has made heating and welding fixtures since 2003 and keeps the spec on file for consistent re-orders.
