Foundry applications | Krautzberger

Different materials in foundry processes

Foundries use media with very different properties. Refractory foundry coatings often contain mineral solids and are applied to sand moulds or cores. Release agents form thin films on patterns, moulds or tools. Marking colours and other process media identify or protect specific areas.

The application must therefore not only create a suitable spray pattern. It must also be able to deal with abrasiveness, sedimentation, high solids and often harsh production conditions.

Spray foundry coatings onto moulds and cores

After drying, foundry coatings form a defined layer between the moulding material and molten metal. They can help improve the casting surface and reduce certain casting defects. The required coating thickness depends on the moulding material, metal, geometry and foundry-coating system.

even wetting of complex core and shape geometries
Controlled layer thickness without runner or material nest
Continuous stirring against sedimentation
sufficiently large material cross-sections
wear-resistant nozzles and components in contact with the material
good flushability at production interruptions

Release agents, form protection and marking media

Release agents are sprayed as thinly and evenly as possible on models, moulds, moulds or tools. Too much medium can cause residues; too little can affect the deformation. For heated tools, evaporation and tool temperature must be taken into account.

Marking paints can identify cores, moulds or inspection states. Depending on the casting process, mould-protection products or other special media may also be used. Material suitability must be agreed with the respective supplier.

Material change, stirring and system maintenance

Foundry coatings and other foundry media can settle or start drying in vessels, hoses and spray guns during stoppages. A coordinated operating strategy therefore includes spraying as well as agitation times, circulation, operation during pauses and flushing sequences. With abrasive media, wear parts should be easy to access and replace on a planned basis.

If different foundry coatings or release agents are processed on the same system, residual quantities and mixing must be considered. Separate material paths or a suitable material changeover and flushing concept may be needed. Cleaning is evaluated in the technical centre with the original medium because residues and solubility can differ considerably.

Continuous or intermittent stirring
Pause and restart concept
wear-related maintenance
separate material paths for incompatible media
cleaning with an approved flushing medium

Krautzberger spraying technology for abrasive media

For foundry coatings with a high solids content or abrasive properties, the focus is on spray guns with large material passages, suitable nozzle designs and wear-resistant material pairings. Depending on the medium, needleless or diaphragm-sealed devices can offer advantages in flushability and wear.

The material can be supplied via agitator tanks, material pressure vessels or suitable pumps. Material pressure regulator stabilizes the application at the spray gun. Circulation and continuous movement of the medium shall be checked for longer lines or more apparatuses.

Automation of complex geometries

Moulds and cores often have deep contours, undercuts and varying geometries. Automatic spray guns can be mounted on axes, lifting devices or robots. Round and flat spray patterns, different nozzle angles and extensions allow the equipment to be adapted to the shape of the component.

In addition to the spray path, drying, handling and soiling of the system must be taken into account. A controlled spraying area reduces deposits on grippers, sensors and conveyor technology.

Typical areas of application

Sand moulds and cores in iron, steel and non-ferrous casting
complex core packages and interior contours
Models, mould plates and tools
Mould and die casting processes with suitable separation media
Marking and process media in foundries

Manual workplaces and automated cells

Large shapes, changing cores and repair tasks are often coated manually. Here, robust manual spray guns and a well-controlled material supply are crucial. With recurring core and shape geometries, automatic webs can keep the layer thickness more even.

In automated cells, spray gun, component position and material flow are coordinated. Protective measures against dust, splashes and abrasive residues increase the availability of the plant.

Robust manual spraying stations
automated processing of recurring geometries
Protection of axes and sensors
well-accessible maintenance and cleaning areas

Advantages of a coordinated application

even layer on complex geometries
less clogging thanks to suitable material passage cross-sections
reduced wear due to suitable material selection
stable application quantity and reproducible processes
good rinsability and shorter cleaning times
Flexible manual and automatic integration

Tests with the original foundry coating or release agent

Solid content, grain size, viscosity and sedimentation behaviour differ considerably. Original material and sample form can be tested in the Krautzberger technical test centre. In doing so, conveyorability, stirring concept, spray pattern, layer distribution, wear behaviour and cleanability are evaluated.

The casting performance of the foundry coating or release agent is then validated by the operator together with the material supplier.

Go to technical center

Related products

All products

Suitable solution for your foundry process

Are you looking for a spray gun, a robust material supply or an automated solution for foundry coatings, release agents or marking media? Krautzberger supports you with technical design.

Talk to us about medium, solids content, geometry, cycle time and cleaning requirements.

Get in touch

Application: Reliably spray refractory coatings, release agents and process media in foundries