Latex tubing extrusion 1

[NLz]

My company would like to try to extrude latex tubing. We do thermoplastic extrusion now. From any of you in the field, is this an extremely difficult product to make? Will I want to pull my hair out?

 

[GrahamBennett]

You will be bald within the week because the two fields are not the same. Different equipment is needed because the technologies are radically different.

Latex extrusion demands 30 - 40m long coagulation baths, naked gas flames, aqueous dispersions of all the required chemicals, peristaltic pumps, header tanks set on top of a 10m high mezzanine floor. Need I go on?

 

[NLz]

yes, tell me everything....I'm waiting or a consultant's call.

Thanks!

 

[GrahamBennett]

I know how to extrude latex thread but tubes are not that different. If you are not based in East Asia the costs of production will not be covered by the price paid for the product.

OK. To start with you will need a supply of glass tubes (dies) with torpedos within the bore to provide the various inner and outer diameters required - not easy to find. A supply of ready-made dispersions (not cheap but far, far easier than to produce your own). (If you want to produce your own dispersions then you will need a number of ball mills to pulverise the chemicals.) A tall building with a mezzanine floor at least 10m high to provide a reasonably constant header pressure. Two or three latex compound storage tanks (at least 2500lt capacity). Peristaltic pumps to maintain a constant head in the storage tanks. (Normal pumps will cause premature coagulation of the latex.) Pipework and tubing to connect tanks to glass dies. Coagulant tanks at least 30, probably 40, metres long. A supply of coagulant. Washing/leaching tanks (at least 2, both 40m long). Gas burners to dry and cure the latex. Collecting and packing equipment. That's it on a basic level.

The greatest challenge will be to maintain equal pressures at the dies so many threads/tubes can be extruded at the same time to maximise productivity. Therefore some means of regulating the latex flow to the dies is essential.

 

[NLz]

Thanks a lot for your time!

What kind of pressures are involved ?

I have yet to talk to the consultant. Our production needs are "rather" small and perhaps a downsized scenario may be possible. Who knows, maybe we can dip it...

Nelson

 

[GrahamBennett]

What pressures?

Can't say at the moment but they should be easy to calculate from the diameter of the tanks, the "head" or height difference between the dies and the surface of the latex mix in the tank, etc.

You could dip them, as you suggest. Now you're getting into a slightly different technology area. See if you can find anything about manufacturing latex catheters.

 

[GrahamBennett]

I just posted a reply and it's disappeared. Pressures? Fairly low, easy to calculate.

Dipping is a different area of latex technology. See if you can find anything about manufacturing catheters.