Shrinking parts with dry ice 1

[fareng]

I have seen dry ice used for shrinking fittings but I am not sure if I should use dry ice alone or with a liquid?

 

[Kenneth]

A low freezing point liquid is used to make the bath. Acetone or alcohol (both flammable) are often used.

http://www.amer-rest-equip.com/usare_other_uses_dry_ice.html

http://www.linde-gas.com/International/Web/LG/COM/likelgcomn.nsf/DocByAlias/ind_shrinkfitting

Wear proper gloves and a face shield.

Slowly add small amounts of the solid dry ice to the solvent to avoid excessive frothing and overflow of the solvent.

 

[fareng]

Thanks
That was what I needed to know

 

[griffengm]

Not sure if it gets as cold as alchohol bath but I have used household ammonia with dry ice with good results.

Griffy

 

[ledon]

Be careful with ammonia. It tends to attack certain metal alloys.

 

[automatic2]

I've used dry ice alone on several occasions with good results.

 

[magnetchief]

We use liquid nitrogen with great results.
But, be sure to use ppe.

 

[ajack1]

How much are you looking to shrink the part by? Even a common household freezer will work, with no safety issues, however still wear gloves.