+x

 

Jonathan Cappola - 4/10/2019 5:36:08 PM

Hi all,

I'm in the process of getting ready to pour a cylindrical tube out of epoxy or polyester resin. It is 0.5" thick walls with an ID of 14". The cast will be 30" tall and needs with withstand internal pressures of 45psi.

I have obtained metal duct work for the mold sides and an environmental chamber to cast the piece in. I'm looking for any advice on how to apporach casting something of this size (~3gal). Would I have to pour in layers or would it be possible to pour all at once? What sort of resin would be recommended for such a task?

Thank you,

Jon

+x

 

Jonathan Cappola - 4/11/2019 12:45:25 PM

+x

 

Lester Populaire - 4/11/2019 12:19:38 PM

+x

 

Jonathan Cappola - 4/10/2019 5:36:08 PM

Hi all,

I'm in the process of getting ready to pour a cylindrical tube out of epoxy or polyester resin. It is 0.5" thick walls with an ID of 14". The cast will be 30" tall and needs with withstand internal pressures of 45psi.

I have obtained metal duct work for the mold sides and an environmental chamber to cast the piece in. I'm looking for any advice on how to apporach casting something of this size (~3gal). Would I have to pour in layers or would it be possible to pour all at once? What sort of resin would be recommended for such a task?

Thank you,

Jon

So you want to build a pressure vessel of a substantial size out of resin only? this seems like a very dangerous idea to me...

It is a low pressure application. I ran a handful of tensile tests per ASTM D638 on some epoxy I had on hand to get some idea of the elastic modulus and the yield strength. The hand calcs and the FEA suggest that its quite safe up until about 60 PSI assuming I can pour the bulk without any notable defects under the loading conditions we've prescribed.

I am, however, not sure how to approach such a large cast as most epoxy resin casting I do is for sample holding for nanoindentation as those are very small molds (1.25" OD cylinders).

+x

 

Lester Populaire - 4/11/2019 1:09:21 PM

+x

 

Jonathan Cappola - 4/11/2019 12:45:25 PM

+x

 

Lester Populaire - 4/11/2019 12:19:38 PM

+x

 

Jonathan Cappola - 4/10/2019 5:36:08 PM

Hi all,

I'm in the process of getting ready to pour a cylindrical tube out of epoxy or polyester resin. It is 0.5" thick walls with an ID of 14". The cast will be 30" tall and needs with withstand internal pressures of 45psi.

I have obtained metal duct work for the mold sides and an environmental chamber to cast the piece in. I'm looking for any advice on how to apporach casting something of this size (~3gal). Would I have to pour in layers or would it be possible to pour all at once? What sort of resin would be recommended for such a task?

Thank you,

Jon

So you want to build a pressure vessel of a substantial size out of resin only? this seems like a very dangerous idea to me...

It is a low pressure application. I ran a handful of tensile tests per ASTM D638 on some epoxy I had on hand to get some idea of the elastic modulus and the yield strength. The hand calcs and the FEA suggest that its quite safe up until about 60 PSI assuming I can pour the bulk without any notable defects under the loading conditions we've prescribed.

I am, however, not sure how to approach such a large cast as most epoxy resin casting I do is for sample holding for nanoindentation as those are very small molds (1.25" OD cylinders).

technically it should be quit an easy pour as the wall thickness is rather small so heat dissipation should not be an issue with a casting resin. however, epoxy is really brittle which is bad for pressure tanks as the damage tolerance is very small. energy is force times pressure which shows that your low pressure application still contains about a tenth of the energy of a hand grenade. wouldn't wanna be anywhere near that thing when pressurized.

+x

 

Jonathan Cappola - 4/11/2019 1:54:07 PM

+x

 

Lester Populaire - 4/11/2019 1:09:21 PM

+x

 

Jonathan Cappola - 4/11/2019 12:45:25 PM

+x

 

Lester Populaire - 4/11/2019 12:19:38 PM

+x

 

Jonathan Cappola - 4/10/2019 5:36:08 PM

Hi all,

I'm in the process of getting ready to pour a cylindrical tube out of epoxy or polyester resin. It is 0.5" thick walls with an ID of 14". The cast will be 30" tall and needs with withstand internal pressures of 45psi.

I have obtained metal duct work for the mold sides and an environmental chamber to cast the piece in. I'm looking for any advice on how to apporach casting something of this size (~3gal). Would I have to pour in layers or would it be possible to pour all at once? What sort of resin would be recommended for such a task?

Thank you,

Jon

So you want to build a pressure vessel of a substantial size out of resin only? this seems like a very dangerous idea to me...

It is a low pressure application. I ran a handful of tensile tests per ASTM D638 on some epoxy I had on hand to get some idea of the elastic modulus and the yield strength. The hand calcs and the FEA suggest that its quite safe up until about 60 PSI assuming I can pour the bulk without any notable defects under the loading conditions we've prescribed.

I am, however, not sure how to approach such a large cast as most epoxy resin casting I do is for sample holding for nanoindentation as those are very small molds (1.25" OD cylinders).

technically it should be quit an easy pour as the wall thickness is rather small so heat dissipation should not be an issue with a casting resin. however, epoxy is really brittle which is bad for pressure tanks as the damage tolerance is very small. energy is force times pressure which shows that your low pressure application still contains about a tenth of the energy of a hand grenade. wouldn't wanna be anywhere near that thing when pressurized.

I'm decently confident in the engineering analysis to determine its safety. It will be operating at about 10PSI on average. Do you think I could use an epoxy resin and pour it all at once or should I consider layering the pours? Would polyester resin be a better option if I wanted to pour the entire thing pretty much at once?