Mollart Engineering's half-million pound China-destined machine accepted

1 min read

A £500,000 Mollart Prismabore combination two-spindle milling and gundrilling cell for producing a range of four different rocker arms for use in large marine diesel engines has been accepted by Mollart Engineering's Chinese customer.

Two weeks of extensive acceptance trials and in-depth deep hole drilling process training for a team of Chinese engineers involved with the end application were the prelude to the acceptance. The trials, carried out at the Chessington, Surrey plant of Mollart Engineering, involved the milling of a series of boss and face features on the heavy alloy steel forgings, together with the gundrilling of various oil feed holes, some at compound angles, of 6.8 mm and 8 mm diameter that were up to 220 mm deep. The Prismabore PRB-40 twin spindle machine has a drilling capacity between 3 mm and 40 mm dia by up to 1,500 mm deep. Controlled by Fanuc 31i-Model B, it has an X-axis of 2,000 mm, a Y-axis of 1,000 mm, an independent ram with a stroke of 850 mm to form the Z-axis and a U -axis for drilling depths up to 1,500 mm. The B-axis driven rotary table is 1,200 mm square with a 10 tonne loading and each axis is fitted with the high accuracy linear scale option for the Chinese customer. Both the drilling and milling spindles, sited side by side, are independently driven for maximum flexibility. The ISO 50 taper milling spindle is powered by an 11 kW drive and the drilling spindle by a 15 kW motor. Through and around the tool is high pressure coolant feeds which can be set at up to 110 bar. Renishaw tool probing and tool length measurement is also fitted.