The alarm about the accident came at 02.16 on Monday night.
Rescue services and staff at the company managed to free the man.
Due to the critical situation, an anesthetist was called and the man was put to sleep on the spot.
He was later taken by ambulance to Ryhov County Hospital.
The condition is serious.
"A serious incident"
According to the site manager at the company, it is too early to say anything about how the accident happened.
- We do not know what happened and right now there is a safety stop.
A technical investigation into the cause will begin.
It is a serious incident, says Tomas Lindstrand at Ahlström-Munksjö.
The police have drawn up a report of causing bodily injury through a workplace accident.