Straws!?

Does anyone know how straws are made? :confused:

Extruded, I would guess. The bendy straws, on the other hand…not sure!

they put the bend in afterwards.

http://www.straws.co.kr/product2_eng.htm
http://business.com.tw/jumbo/home.htm (bottom of the page)

Surely this tops the chart for exciting topic of the day??

Wild guess here, but the bendy straws are probably blow-molded after being extruded.

Extrusion followed by corrugator on still-soft pipe for the “accordeon” part, guys.

Think simple.

thoroughly fascinating…

Marge! Grab me another beer!

extrusions with:

1 - as said before, blow moulding in to a corrugated-type mould

2 - or the inverse…a vaccum.

sometimes the corrugated section is in two parts (like a 2 part injection mold)…or like two gears, which mesh together upon rotation. The outside circumfrence is equal to the length of the straw, and the ‘geared’ bit only takes up part of it (it sometimes has a blade at the end of splitting the extrusion length.

HTH

bored were we Paul?

not bored…just on a ‘break’ :smiley:

I had to look into it for my RSA entry…so I’m just a little more knowledgeable now…plus i found it fascinating :confused: LOL

iI would think it will be similar to that of a soda bottle,. Blow moulding for the body and separate treatment for the threads but done at the same time. Of course straws will only need extrusion. Is blow moulding needed to get the shape? Won’t extrusion be enough?

it’s not blow moulding as such (like into a closed mould)

pressurised air is passed through the extrusion to prevent it from collapsing (it’s still warm from extrsuion) and to push it into the bendy bit mould