precision-tubes & hydraulic cylinders

Precision tubes and cylinders are used in many areas:

These applications are demanding:

small tolerances for sealing surfaces of the order of 5 mikrons
tight tolerances for parallelism and right angles of main axes
perfect surface-finish smaller than Rz = 1 (super-finish)
reduced cost through series-production
additional features on the tubes
special materials
starting materials are sometimes not tubes, but massive shafts
carefully rounded radii, especially for high-pressure and pulsating pressure applications
hardened surfaces through partial induction hardening
corrosion protection by galvanizing with nickel or chrome
need for cost-reduction through series-production

Highest specifications are requested for ground and honed hydraulic cylinders:

If the original material is a casting, it has to be pressure tight
for honing and grinding large and special machines are needed
sometimes the final surface is protected by a thin layer of hard-chrome, sometimes a thin oil film will do
the combination of ground dimensions with small tolerances in cubic and rotative areas requires complex production strategies
there are not many experts working in these dimensions between 500 and 1500 mm!

We are a series-supplier for these components and: