Special-purpose drilling machines

Chessington-based Mollart Engineering (www.mollart.com) has won an order from a European producer of food pellets for three special-purpose eight-spindle deep-hole drilling machines to form a cell that will be used to make dies for the pellet extrusion process.

The three LD8 150 gun-drilling centres have eight synchronous axes, plus two Y and B axes. Each machine involves radially positioned gun-drilling spindles set around an indexing table that is programmed to rise and fall in order to create multiple layers of close-pitched holes.

The holes — between 1.6 and 12mm in diameter and up to 150mm deep — are drilled simultaneously in the tubular die components that are used to extrude pellet material under pressure.

Mollart has developed a bespoke coolant system that is being fabricated and assembled at its sub-contract facility in Resolven, South Wales, before being shipped to Chessington.