01
Wet filament winding
Glass roving runs through resin and is wound at an angle onto a rotating steel mandrel. That is how we make tubes, cylinders and rods.
The tubesAbout
A family firm from Popovo, Bulgaria. Boris Harkov runs it and Todor Harkov is the engineer.
02
Hand lay-up
Glass mat or woven fabric is laid by hand in a mould and wetted out with resin. That is how we make signs, covers, hulls and tank linings.
The productsFrom the workshop
Roving through the resin bath
A tube on the mandrel
A finished conical tube
An insulating ring
How a tube is made
- 01
Mandrel
We choose it by the inner diameter. If there is none, we make a new one.
- 02
Roving and resin
The strands run through the bath and come together in a band.
- 03
Winding
The angle and the number of layers depend on what the tube has to carry.
- 04
Curing
The resin cures while the tube is still on the mandrel.
- 05
Extraction
We pull the mandrel out, so the section cannot have undercuts.
- 06
Finishing
We cut to length, machine the outer diameter and drill holes.
