Solutions for Fluid Technology

Tractor with baler at work in the field.
For the materials often used in fluid technology, cast iron, steel, stainless steels and non-ferrous metals, MAPAL offers economical process solutions through a high level of expertise in both bore machining and milling applications. Customers have relied on MAPAL's expertise for many years, particularly for demanding machining operations for hydraulic parts in a wide range of dimensions.

Everything depends on the main bore

Manufacturing valve housings is the supreme discipline in the hydraulics world. For many years, MAPAL’s expertise has been in demand for the spool bore. The gap dimension with the slide depends on the accuracy of this bore, which is very narrowly defined in modern hydraulic valves, so that the hydraulic oil can only flow in the required direction. The roundness, straightness and surface finish of this bore are also crucial.

The first machining step takes the varying quality of the blank parts into account. Since the pre-cast bores are relatively imprecise, a precise pilot bore must first be created in the first ridge. This lays the foundation for creating a good cylindrical form in the subsequent machining steps. Next, a solid carbide tool or, in the case of larger parts, a tool with indexable inserts passes through the entire bore. What the pilot drill has created for the first ridge is now produced along its entire length. To prevent ring formation in the hollow chambers due to chips, MAPAL ensures a soft cut during machining by using tangential technology. This can eliminate the need for a separate washing cycle in the process.

MAPAL fine boring tool with an adjustable cutting edge and guide pads

After this pre-machining, the classic fine boring tool is used, finishing the bore extremely precisely. It has an adjustable cutting edge and guide pads, which prevent the tool from being displaced from ridge to ridge. This produces a high degree of straightness and an exact cylindrical form.

The bore quality can usually be improved to such an extent that the sometimes still necessary three-stage honing process can be reduced to a one- or two-stage honing process, or honing can even be eliminated altogether. However in cases where three stages are still needed, this process is considerably faster thanks to the good pre-machining.

High cost-effectiveness with standard tools

In the machining of hydraulic parts, the focus is also on enabling economical machining with the available standard portfolio. Examples of this include the NeoMill programme for face milling or the Tritan-Drill-Reamer that combines drilling and reaming in one operation and guarantees best drilling results with the new UNIQ DReaM Chuck 4.5°.

Efficient machining with tangential boring tool

Tangential boring tool with indexable inserts

The parts are 500x500 mm valve blocks made of spheroidal graphite cast iron 50, with three piston bores to be machined from both sides. Stock removal can amount to 16 mm in diameter. The tangential boring tools with indexable inserts produce short rip chips, preventing rings from being pressed into the gaps which then have to be removed at great expense. The operation time has been reduced by 15.33 minutes per part. The housings of the corresponding model were produced in a quantity of 500, which means a total time saving of 128 hours.

Your direct contact

Jochen Schmidt from the Market Segment Management General Machining at MAPAL.

Contact person

Jochen Schmidt Market segment management General Machining +49 7361 585 3893