OT-The complexity of hollow PVC extrusion process, I need to have an appreciation of

I need to have an appreciation of the tooling and specifically the tooling and process in the vacuum cooling/sizing chamber area. I realize that this is a process that is much more complex than a conventional extrusion. I included links (pictures hopefully) to equipment that is either for sale or is part of a product advertisement brochure. In this one piece of equipment that's for sale it appears that the tooling from a job is still in position, it appears like several blocks that have a profile of the shape of the extrusion space down the length of the chamber and that each of these blocks have a way to control the vacuum individually (I'm guessing here) and that the entire chamber holds some degree of vacuum (not a high degree of vacuum) the extrusion and these blocks where water is sprayed upon or is submerged in water that circulates (has a chiller) to cool the extrusion so when it comes out of the chamber, there is a device that grips the extrusion to maintain a uniform stretch (for lack of a better term) in the extrusion. And that each end of the chamber there is some kind of combination of wiping and close fitting opening that is arranged in such a way to allow any water that would slip past one of these multiple stages built into each end of the chamber, possibly with a air knife, so on the way out to make sure the surface is completely dry, so a good grip could be made on the extrusion. Downstream from this would be the sliding cut off saw. All of this would be in a facility that has good humidity control year-round so that the product is consistent and uniform when it is extruded. There are parts of this that I don't know are correct and I'm making assumptions I reach out to the form members and hope that someone has experience or knowledge in the area. If there is an area of suggested reading or other source that I may use to help myself understand the process better I would be very thankful and appreciate any help that can be offered.

16' Conair Vacuum Tank Model MSBH1-16-9, New in 2007 | Plastic Machinery | Used Plastic Equipment | Used Plastics Machinery

Cooling Tanks for Plastics Processing | Conair


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solidworks4u said:

I need to have an appreciation of the tooling and specifically the tooling and process in the vacuum cooling/sizing chamber area.

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Are you trying to design a product that will be made using this process, or are you trying to design a new machine?

For the first, I'd recommend calling up a shop who already does this, or the manufacturer (although they will probably not be interested in talking to you unless you want to buy a machine).

For the second...well, good luck I guess. I would not expect someone to jump into the deep end of the pool like that.

Many thanks Pariel!Trying to understand enough about the tooling associated with the extrusion process as to make a family of custom extrusions that are close in shape to each other, understand the ares that can be used to allow some flexibility in the design of the extrusion profile. In addition a family of tooling to reduce the cost, to set up the 1st run, the thinking is modular tooling or capable to accommodating a family of extruded profiles without cutting specific tool for each extrusion shape.

That certainly sounds like you should be talking to whoever is going manufacture it for you as it's going to be machine specific. Can't say I have experience with this type of extrusion, but in general I have not seen cost benefits to modular extrusion dies (simply because they aren't usually all that expensive). In this case maybe there are, as the die may be much longer than what I'm used to.

Many thanks! Pariel, The cost to benefit ratio maybe something like, if the extrusion can say tolerate a "witness line" (where the tool is 2 piece and comes apart for the additional sizes) or if a square corner is desirable for ease of manufacture vs a radius, are what come to mind. And this is not the extrusion die, I can imagine that being a special tool with coolant passages and more. The additional tooling down stream is just as important for me.

thanks!