Can thin plastic tubes be easily injection molded?


part of my design calls for a plastic tube, approx 7mm o/d, 5mm i/d
length 90mm. type of plastic undecided as yet, perhaps abs.

is this straighfoward to do with plastic injection molding?

(apart from pen/biro cases I dont see too many examples out there).

thanks in advance


The sizes seem pretty standard.

Did you try asking a plastic tube manufacturer if they carry that size? Seems like it would be easier to buy stock and cut it down.

Usually tubes are not injection molded parts but made in extrusion
processes. After extrusion you can cut the lenght according to need.

It should be the most cost effective way to adapt your design to a tube
that comes out of existing tooling.


Injection blow molding could be an option, though it might be a specialized machine and pre-form to get that mixture of OD and wall thickness. Draft and undercuts aren’t usually problems because the parts get pushed off the machine with air.

We’re dealing with something similar now, but larger OD and much thinner wall (like .5mm). The plan is for injection molding but we aren’t to that stage yet.

Thanks again for the replies.

Sorry maybe I should have explained a little more:
The design I have at the moment is for two rods (one solid , one a tube) with the solid sliding into the tube. So a telescopic arrangement, with bump stop at the end of the outer rod and a t-piece top of the solid rod, so the solid cant slide all the way out of one end of the outer rod.
So unfortunately likely can’t be bought in from pre existing plastic tubing.

Anyway I think I’ve found an example:

Looks like maybe its not the usual manufacturing approach, but it can be injection molded with long pins. On a side note I was told each pin adds around $800 to the tooling cost for steel molds.

We IM a tube for a suction toothbrush approximately 120mm long, 4mmID and 6mm OD out of PP.

Depends on your draft requirements for the ID.

it’s easy ,don’t worry about it.