Rugged cooling for the best defence

Yes. Defence enquiries reach us above all for development projects, that is for the phase in which the cooling solution is still being created. That is where our strength lies: design by thermal simulation, prototypes in single quantities, then pilot series. Typical tasks resemble those from rail and marine applications: power electronics in sealed enclosures, high demands on shock, vibration and corrosion, service lives spanning decades, and the obligation to be able to reproduce spare parts many years later. One limit, stated honestly: COOLTEC is certified to DIN EN ISO 9001:2015, but we do not hold defence-specific qualifications such as AQAP standards. If your procurement process requires such a qualification, say so before the quotation.

Yes. A fully encapsulated device without air exchange is the norm whenever dust, moisture, salt or protection requirements rule out an open air path. The heat then has to leave through the enclosure wall, and an enclosure with an integrated cooling circuit is the most direct solution for that. It becomes demanding because different loss sources come together: power semiconductors release their heat over a small area, while chokes and transformers do so in a distributed way and at a higher permissible temperature. In practice you therefore create zones of different cooling capacity within one part instead of using the same structure everywhere. One limit: without moving air inside the enclosure, the cold wall only helps components that have a thermal bridge to it. Components without that connection need heat conduction bridges or an internal fan.

Press-fitted tubes are joined by mechanical form fit and are therefore well suited to shock and vibration loads. The load does not act on a bonded or soldered seam but on a formed joint. The critical points are not the tubes in the plate but free tube ends and ports: an unsupported long tube end acts as an oscillator and breaks at the clamping point. That is why we keep tube outlets short, support them or route them via a fitting directly on the plate body. Against salt atmosphere the surface decides: thicker anodised layers with sealing, and no exposed copper-aluminium pairings. One limit: a test laboratory carries out the verification under your load profile. We design towards it and supply the parts for testing, but we do not run the test ourselves.

Yes, and with long service lives that is the important question. The prerequisite is documentation: we record material, material form, tube geometry and process steps so that a rebuild remains possible years later. That means not just the drawing, but also the information a drawing does not contain. Two points limit repeat production in practice, and they should be settled early: availability of the raw material in the same material form, because cast and rolled material are not interchangeable, and availability of an extrusion profile if the tooling at the press plant has reached the end of its life. One limit: we make commitments about specific periods on a project basis; no manufacturer can seriously give a blanket spare-parts guarantee spanning decades.

For underwater and offshore applications the task shifts from cooling capacity to leak tightness and corrosion: the enclosure has to withstand ambient pressure, and every material pairing in a saltwater environment is a potential galvanic pair. With inverters in a sealed stainless steel enclosure, the route is an internal cold plate bonded to the enclosure wall, so the heat passes through the wall to the surrounding water without seawater ever touching the cooler. The feed-throughs are critical: every fitting to the outside is a leak path and needs a material and sealing system suited to the environment. One limit, stated honestly: pressure vessel calculation and approval of the enclosure for diving depths are not part of our scope. We supply the thermal component inside it.

For every item we supply the export data: AL number under the German export list, ECCN under US law, statistical commodity code (HS code) and country of origin. This is routine for us, because series customers in power electronics require it before a quotation is even assessed, and because it is part of supplier onboarding at large corporations. To classify the products themselves: heat sinks and cold plates are civilian parts with no military function of their own. Whether a specific shipment requires a licence is not decided by the cooler but by your end product, the end use and the destination country. State both in your enquiry and we will clarify it before the quotation. Confidentiality runs via your NDA template or ours. One limit: we do not run the licensing procedure for your end product. That lies with the exporter of the end product.

We start from your load case: heat load, distribution across the area, permissible component temperature, inlet temperature, volume flow and installation space. That gives the Rth budget, which we test in thermal simulation against variants of the channel routing, before any design work begins.

We look not only at the maximum load case but at the temperature cycles over the service life. What matters are differences in expansion between materials and the resulting stresses in joints.

We work with copper, copper-nickel, stainless steel and aluminium. The choice follows three criteria: thermal conductivity, media compatibility and mechanical requirement. We often combine them: conductive material at the heat source, resistant material at the medium.

Pressure testing of every part is our standard; for demanding applications we additionally test with a helium leak test and document the leak rate per part. We set the target leak rate before design.

We build anything from a 30 mm microchannel cooler to a 3 m (30,000 mm) cold plate, right up to a fully cooled large precision part. Size alone does not decide what is possible: material, design and tolerance do. Give us your dimensions and we will tell you in which design we can produce them.

Yes: housings, structural parts, stators and drives. With mechanical parts it is often less about maximum heat removal than about keeping the temperature gradient small, because the gradient creates the deformation.

Yes. Framework contracts, stockholding and last-time buy are part of our standard offering. We also reproduce parts whose original supplier is no longer available.

Samples in around 6-8 weeks as standard, 2-4 weeks by express. For series production we manufacture in a highly automated plant in Germany; cost-sensitive standard parts come from our joint ventures in Asia.

Yes, that is the norm for us. We sign your non-disclosure agreement or provide ours. We never pass on customer projects or application details.