Horizontal CNC milling drilling machine Four-Star TBM and TRM

The TBM and TRM series by Four-Star are two variants of a CNC horizontal boring and milling machine with T-bed configuration, designed for precision machining of large components: gearbox housings, cylinder blocks, turbine casings, heavy machinery frames, and structural parts requiring combined boring, milling, and drilling operations in a single setup.

The T-bed architecture combines longitudinal table travel (X axis, 3,200 mm), transverse column travel (Z axis, 1,600 mm), vertical headstock travel (Y axis, 2,000 mm), and spindle extension (W axis), together with rotary table indexing (B axis). X and Z axes use roller linear guideways; the Y axis incorporates box guideways (boxway) to maximize rigidity and damping under heavy cutting loads. All four linear axes include linear scales as standard equipment.

The key distinction between variants is the W-axis element: the TBM uses a boring bar of Ø130 mm with 700 mm W travel, suited to precision boring of large-diameter, deep holes; the TRM uses a RAM (box-type headstock) with 800 mm travel, supported on four steel rails with INA roller bearing blocks, offering greater versatility for face milling and complex machining operations.

The 1,800×2,000 mm rotary table carries up to 15 tons with 0.001° indexing. The spindle operates at up to 2,500 rpm and 30/37 kW (continuous/30 min), with maximum torque of 2,055/2,535 Nm, driven by a two-stage gearbox (1:5.5) plus pulley (1:1.5). The 40-tool ATC magazine accepts tools up to 500 mm long and 25 kg. Linear axis positioning accuracy is ±0.005 mm, with repeatability of ±0.0025 mm; the B axis achieves ±5" positioning and ±4" repeatability.

The standard CNC is FANUC 0iMF. Optional toolheads include 90°, universal, contouring (Cogsdill ZX), and facing heads; 60- and 90-tool magazines are also available.

The TBM and TRM series target manufacturers in the energy, petrochemical, marine, railway, and heavy machinery sectors that require high-precision boring and milling on large workpieces within a single machining cycle.