Thermal Expansion of hollow features?

[Overheal]

Just a concept check: a 1/2" 6061 hex-bolt with a 3/8" threaded bore in the middle of it (closed on one end and threaded into another body). A steel heating element is installed in the 3/8" bore. When the Aluminum bolt expands, does the geometry of the 3/8" bore compress (tighten on the element) or expand on the element and potentially loosen?

 

[Dougt115]

Expands and will loosen. Metal expands when heated so the circumference of the ID will lengthen increasing the radius. Only issue to watch for is dissimilar metals having different CTEs.

 

[KENAT]

Hi school lab.

A metal ball & ring sized so that at ambient the ball didn't go through the hole in the ring.

Once it got hot enough though...

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[KENAT]

May be a bit trickier than that with individual material properties of different parts, heat transfer over the boundries etc. but generally speaking...

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[MintJulep]

thread391-246558

 

[Overheal]

Thanks fellas!

 

[MikeHalloran]

Whether the 6061 hex-bolt is threaded into an aluminum or steel or other material body, and the thread classes involved, probably makes a difference.




Mike Halloran
Pembroke Pines, FL, USA