Machining HK30 (ASTM A351 or A608)

Machining

Most machining operations can be performed satisfactorily on castings of HK alloy. It is

important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the

surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should

be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed

steel and carbide tools may be used successfully.

Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most

important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil

containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools.

Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with

carbide tools.

Information on the procedures for specific machining operations is contained in SFSA Steel Casings

Handbook, 6th Edition, Chapter 26.