Case 1: 40Cr Transmission Shaft – From Bar Stock to Finished Part in One Setup
A typical workpiece is a Φ60 × 1200 mm 40Cr transmission shaft with multiple journals, two keyways and an M48 thread on one end. Using the CK6140 with a hydraulic chuck on the spindle and a live center on the tailstock quill, the operator completes outer diameter roughing, finishing, grooving, and threading in a single program. With a roughing depth of 4 mm at a feed of 0.3 mm/r in low gear, and finishing at 0.15 mm/r in high gear, total cycle time on this part typically falls between 9–11 minutes, comparable to lathes priced 30–40 % higher. The 1500 mm bed length combined with the tailstock support is the key enabler for this kind of long-shaft work.
Case 2: HT250 Cast Iron Flange – Interrupted Cutting on the Outer Profile
For a Φ320 × 60 mm cast iron flange with bolt holes already pre-cast, the challenge is interrupted cutting on the outer rim and OD. Here the HT250 flat bed of the CK6140 shows its value: the heavy bed mass dampens the shock load from cast skin and intermittent contact, allowing carbide inserts to maintain a 3 mm depth of cut at 180 m/min surface speed without chatter. Compared with thinner-bed economy lathes, tool life on this type of flange work improves by roughly 25–35 %, and the surface finish on the sealing face routinely reaches Ra 1.6 μm directly from the lathe, eliminating a downstream grinding step.
Case 3: V-Belt Pulley with Multiple Grooves – Form Tool Efficiency
A typical 4-groove SPB-section V-belt pulley (Φ250 × 75 mm) involves OD turning, bore boring, and four trapezoidal grooves. On the CK6140's 4-station electric turret, the operator can mount: (1) external roughing tool, (2) external finishing tool, (3) form grooving tool for the V-grooves, and (4) boring bar – completing the part in a single setup. Indexing between stations takes only 1.5 seconds, and the total cycle time for one pulley typically lands at 6–8 minutes. For batch production runs of 200–500 pieces, this efficiency directly improves shop throughput.
Case 4: Steel Bushing Series – Bar Feed Production with Φ82 Spindle Bore
For series production of Φ50 × 80 mm steel bushings from Φ45 mm bar stock, the optional Φ82 mm spindle bore version of the CK6140 allows the use of a hydraulic bar feeder. With a pneumatic chuck and automatic bar feeder, the machine can run unattended for 30–60 minutes per bar, cutting labor cost per piece significantly. Cycle time per bushing typically falls below 90 seconds including parting-off, and dimensional consistency within ±0.02 mm is easily maintained throughout a full bar run – which is what high-volume bushing, spacer, and coupling production demands.
Summary: Where CK6140 Earns Its Place on the Shop Floor
Across these four common workpiece types – long shafts, cast iron flanges, V-belt pulleys, and steel bushings – the CK6140 consistently demonstrates the same advantages: enough bed rigidity for heavy and interrupted cuts, enough spindle torque for steel and cast iron, a reliable 4-station turret for multi-feature parts, and a CNC system that operators already know. None of these are headline-grabbing features, but together they explain why the CK6140 remains the default choice for shops producing general machinery, auto parts, fluid power components, and agricultural equipment parts at moderate to high volume.
➡️ For a detailed cycle-time evaluation on your specific parts, sample programs, or a configuration matched to your bar diameter and CNC preference, click here to contact the HAIDI Machine sales engineering team.