Tungsten Carbide Ball Fitting

Tungsten carbide ball fitting are a unique category of balls because they are manufactured in a sintering process, whereupon the metal powder is formed under extreme heat and pressure.  Tungsten carbide ball fitting are extremely hard (92 Rockwell).  The manufacturing technique makes these balls substantially more expensive than other materials, but practically inert. Their relative inertness makes them extremely resistant to interaction with various liquids and alloys.

Tungsten carbide ball fitting can be found in heavy machinery applications, since they are much stronger than stainless steel or chrome.  Particularly, tungsten carbide ball fitting have been used industrial sprayers to regulate the flow of fertilizers or pesticides to crops. 
Due to the strength of tungsten carbide, the balls are frequently used in the downhole tool industry for hard banding.  These are critical applications for the petroleum drilling industry.