The Winding Machine
The Winding Machine
The Winding Machine – Franke Bearings
About Our Customer
SAHM celebrated its 75th anniversary in 2020. An important station in the successful history of the company was the construction of rewinding machines for household sewing thread bobbins.
Today, SAHM focuses on winding machines for technical yarns made of synthetic materials. SAHM machines are used, for example, to precisely wind carbon fibres for car body construction, security strips for bank notes, monofilaments and fibrillated tapes for artificial turf or surgical sewing threads.
100 kilometers of fiber on a bobbin
SAHM’s core competence lies in winding any material in such a way that it can be further processed without any problems. Winding parameters such as winding speed and thread tension differ from material to material. “Carbon fibres, for example, are very demanding because the material is susceptible to filament breakage,” explains SAHM head of development Heiko Ebhardt.
Particular attention must therefore be paid to the filament guidance.” The range of spooled materials is wide. The carbon precursor material polyacrylonitrile, for example, is wound into spools weighing up to half a tonne. At another extreme are ultra-fine monofilaments, where 100 kilometres of thread can fit on one core.
Finding the right technology and the optimal winding parameters for every winding task is SAHM’s great strength. “We see ourselves as a development partner for our customers,” says Heiko Ebhardt. In this way, SAHM can always guarantee an optimal winding result: absolutely uniform and gentle on the material.
Another characteristic of SAHM is the long service life of its machines. “There are many machines that have been in the field for 50 years and are still working perfectly,” says the head of development, not without pride
Productivity Through Automation
SAHM winding machines are used, among other things, in the production of man-made fibre material. In order to be able to wind continuously produced threads without rejects, SAHM has developed automatic winding machines.
When one tube is fully wound, the machine switches to the second, still empty tube within seconds and fully automatically. SAHM offers automation solutions for the fully automatic supply and removal of cores and full bobbins.
” In tests with our own design, we had the problem that it broke down because of vibrations and then had too much clearance. This no longer happens with the Franke slim bearings. “ – Heiko Ebhardt, SAHM Head of Development
Franke Bearings in Action
For its automatically changing winding machines, SAHM uses thin-section ball bearings and linear guides from Franke. The thin-section bearings for SAHM are customised. By chamfering the races, a defined preload can be set.
“This is a clever principle from Franke, because the desired preload is achieved without requiring additional material or space for it,” finds André Wegner from the industrial agency AnWeTec, Franke’s sales partner in northern Germany.
With the Franke thin-section bearings, a drum is supported in the winding machine, the rotation of which causes the automatic bobbin change.
The technical challenge here lies primarily in the compensation of vibrations to which the bearing is exposed: “Wherever winding takes place, micro-vibrations always occur; this can never be completely ruled out,” explains Heiko Ebhardt. “In tests with our own design, we had the problem that it broke down because of vibrations and then had too much clearance. With the Franke slim bearings, this no longer happens.”
Profile Franke Solutions
– Customised slim bearings based on the Franke LSA type.
Advantages used: individual preload, compactness, economy
– Franke linear guides type FDA
Advantages used: low sliding resistance, long service life