The Haas Automation ST-55S is an industrial-grade CNC Lathes & Turning Centers powered by the Standard CNC. a top spindle speed of 1,000 RPM, and a 3-axis kinematic layout. It supports standardized digital factory monitoring via MTConnect.
Haas ST-55S: big-bore lathe with a 12.5 in (318 mm) spindle bore, A1-20 nose front and rear, 4,250 ft-lbf at 30 rpm and 44 in of Z travel.
| Standardized Parameters & Ratings | |
|---|---|
| Manufacturer (Brand) | Haas Automation (United States) |
| Machine Type | CNC Lathes & Turning Centers |
| CNC Controller System | Standard CNC |
| Number of Controlled Axes | 3-Axis Simultaneous / Positioning |
| Maximum Spindle Speed | 1,000 RPM |
| Spindle Motor Rating | 55.0 kW |
| Spindle Taper Interface | Standard |
| Industrial IoT Protocol | MTConnect ANSI/MTC1.4 Compliant (Ethernet/TCP) |
| Max Swing | 35.5 in (902 mm) |
| Max Turning Diameter | 30 in (762 mm) |
| Max Turning Diameter With Bmt75 Turret | 27.5 in (699 mm) |
| Max Turning Length | 44 in (1,118 mm) |
| X-Axis Travel | 20 in (508 mm) |
| Z-Axis Travel | 44 in (1,118 mm) |
| Rapid Traverse X | 472 ipm (12 m/min) |
| Rapid Traverse Z | 710 ipm |
| Max Thrust X | 5,500 lbf (24,465 N) |
| Max Thrust Y | 2,300 lbf (10,231 N) |
| Max Thrust Z | 9,000 lbf (40,034 N) |
| Spindle Nose | A1-20 Front & Rear |
| Spindle Drive | 2-Speed Gearbox |
| Spindle Motor Power | 55 hp (41 kW) |
| Max Spindle Speed | 1,000 rpm |
| Spindle Torque | 4,250 ft-lbf @ 30 rpm (5,762 N·m @ 30 rpm) |
| Spindle Bore | 12.5 in (318 mm) |
| Tailstock Taper | MT6 |
| Tailstock Travel | 42 in (1,067 mm) |
| Tailstock Max Thrust Acme | 3,000 lbf (13,345 N) |
| Tailstock Min Thrust Acme | 200 lbf (890 N) |
| Turret Stations | 12 |
| Turret Od Vs Id Tools | Any Combination (will vary with turret) |
| Turret Tooling | BOT |
| Coolant Capacity | 95 gal (360 L) |
| Air Required | 4 scfm @ 100 psi (113 L/min @ 6.9 bar) |
| Inline Air Hose | 3/8 in |
| Air Coupler | 3/8 in |
| Air Pressure Min | 80 psi (5.5 bar) |
| Electrical Low | 220 VAC 3-phase, 105 A |
| Electrical High | 440 VAC 3-phase, 53 A |
Haas Automation publishes a list price of US$330,995 for the Haas ST-55S (verified 2026-10-02). Options, tooling, freight and installation are extra, so a dealer quote will differ. A specific price can be requested at https://machinetoolindex.com/machines/haas-st-55s#price; the request is passed to Haas Automation or an authorised dealer.
The spindle bore is 12.5 in (318 mm), and the spindle nose is A1-20 at both the front and the rear. The table does not give a chuck size or a bar capacity, so the largest stock that actually passes depends on the chucks fitted. Ask Haas for the through-hole of the workholding quoted with the machine.
Travels and turning envelope match: 20 in (508 mm) of X, 44 in (1,118 mm) of Z and a 30 in (762 mm) maximum turning diameter. The spindles do not. The ST-40 has an A2-8 nose, a 4.62 in (117.3 mm) bore, 40 hp (29.8 kW), 1,400 ft-lbf (1,898 N·m) at 150 rpm and 2,400 rpm. The ST-55S has an A1-20 nose, a 12.5 in (318 mm) bore, 55 hp (41 kW), 4,250 ft-lbf (5,762 N·m) at 30 rpm and 1,000 rpm.
An MT6 tailstock with 42 in (1,067 mm) of travel. Thrust ranges from 200 lbf (890 N) to 3,000 lbf (13,345 N). With 44 in (1,118 mm) of Z travel, that is enough travel to bring the centre up to a short ring or back it off for a part near full turning length.
220 VAC three-phase at 105 A, or 440 VAC three-phase at 53 A. Air consumption is 4 scfm at 100 psi (113 L/min at 6.9 bar) with a minimum supply pressure of 80 psi (5.5 bar), through a 3/8 in hose and coupler. The coolant tank holds 95 gal (360 L).
The table lists 12 stations with BOT tooling, and OD and ID tools can be fitted in any combination, varying with the turret. Maximum turning diameter is 30 in (762 mm); the table gives 27.5 in (699 mm) with a BMT75 turret.
