Tungsten Carbide Spray Drying
- Water Based PEG - This system is a water based carbo-wax process.
- Non-Hazardous Liquid Paraffin - This system is a proprietary process for producing a paraffin based Tungsten Carbide Grade Powder.
Both systems yield a high purity powder formulated to meet stringent sintered material specifications along with lot-to-lot consistency that the end user demands. All powder lots are inspected by physical properties and a use test is also performed on all batches. The formulation of the powder batch starts with the selection of base materials and additives required for the product. The raw materials are first selected based on specific powder attributes and controlled chemical specifications. The materials are weighed, blended, and charged into a mill filled with tungsten carbide media. During the milling and spray drying process, the tungsten carbide slurry is kept in constant liquid suspension. Upon completion of milling, the batch is transferred to the spray deck. The spray drying system utilized at Towanda Metadyne Inc. is a counter current, co-current flow system. 200 to 500 Kg batches are available. Once the Tungsten Carbide formulation is sprayed, the spherical tungsten carbide product drops into a collection funnel and proceeds into an inert atmosphere cooling station. The material is transferred under controlled atmosphere conditions to the sifting and blending stations. After blending, the uniform batch is weighted into pails with plastic liners. The batch is sampled and tested using the latest powder laboratory equipment thus ensuring the highest quality grade powder. Once the grade powder batch has been inspected and approved, the batch is released to the inventory hold area. The material processed at Towanda Metadyne Inc. is either used internally or sold to other carbide-producing customers.
The Spray Drying system developed by Towanda Metadyne, Inc. has been designed for "ease of cleaning". After each subsequent run the entire system is flushed and thoroughly cleaned to prevent any cross contamination between material grades or types. This feature of the Spray Drying unit and transfer systems allows Towanda Metadyne, Inc. to offer toll spraying of refractory metals without the concern of cross-contamination.