IMAGE GALLERY: How Boart Longyear makes a drill bit

Drill bits start off as powder which are placed in a graphite mould along with a binding agent. The recipe is a secret, but there are common ingredients.

“The key ones are the diamond that provide the cutting action,” says Lambert. “There is the tungsten that provides the wear resistance of the bit. There are the binders, which will melt and fuse everything together. We also use graphite as a mould because of its high temperature properties.”

Some elements must be placed by hand. The worker below is placing items within a matrix.

“You press [the ingredients within] a mould. Then you add a binding agent to it,” says Lambert. “You run it through a furnace. It all infiltrates to make a unified piece. As for the features of the bits, those are all machined into the mould so they create the shape and water ways and features of the bit.”

Industrial diamonds.

Once completed the graphite moulds, which contain the drill bits, are baked.

The drill bits are too hot to handle. A robot in a caged enclosure removes drill bits from the oven to let them cool.

Drill bits fresh from the oven glow bright in the cage.

Cooled drill bits are let out of the cage and can now be handled.

The moulds are removed.

The bits are lathed and sanded and are now ready for work in the field.

The chief customer request is making drill bits that make the company productive, says Lambert.

“One of the ways of generating productivity is taller crown heights. For a long time we offered crown heights in the standard 12 mm but then we have our stage product, which offer 16 mm and 24 mm. It offers the ability to stay longer in the hole before you have to trip out. We are using larger diamonds, which is a trend in the industry. It allows for higher penetration rates and cutting well is softer ground conditions.”

Visit Boart Longyear at booth 101 at PDAC Convention 2016, March 6-9 in Toronto.