CS1 Large-bore Tie Rod Cylinders
The SMC CS1 is SMC Corporation of America's largest bore tie rod air cylinder, covering bore sizes from ø125mm to ø300mm with strokes up to 2400mm. As an authorized SMC USA distributor, Automation Distribution stocks CS1 series cylinders in lube, non-lube, double rod, air-hydro, and low friction configurations — with accessories including knuckle joints, clevis pins, and rod end nuts available from the same source.
SMC CS1 tie rod cylinder overview
The CS1 is SMC's answer to high-force, long-stroke industrial applications where compact cylinders cannot generate adequate thrust and NFPA tie rod cylinders fall short on bore range. The tie rod construction — four external steel tie rods clamping the end caps to the cylinder tube — makes the CS1 fully field-serviceable: seals, piston, and rod components can all be replaced without specialized tooling, extending service life indefinitely in demanding production environments.
The CS1 is available in both lube and non-lube variants. The lube type (CS1, CDS1 without "N" suffix) requires an oil lubricator in the compressed air supply line. The non-lube type (CS1*N, CDS1*N) is factory pre-lubricated and does not require a line lubricator — the preferred choice in food processing, clean environments, and anywhere oil mist in the exhaust air creates a contamination or maintenance issue.
CS1 series specifications
Bore sizes: ø125mm, ø140mm, ø160mm, ø180mm, ø200mm, ø250mm, ø300mm
Stroke range: Up to 2400mm (single rod); up to 1200mm (double rod)
Operating pressure: 0.05 to 0.7 MPa (7 to 102 psi)
Proof pressure: 1.2 MPa (174 psi)
Operating temperature: –10°C to 60°C (14°F to 140°F)
Fluid: Compressed air
Mounting styles: 7 standard styles — basic (B), foot (L), front flange (F), rear flange (G), double clevis (D), single clevis (C), trunnion center (T)
Cushion: Adjustable air cushion standard on both ends for noise damping at end of stroke
Auto switch: Auto-switch capable; built-in magnet available (CDS1 prefix)
Rod end accessories: I-type single knuckle joint, Y-type double knuckle joint, clevis pin, rod end nut — all available by bore size
CS1 series variants
C(D)S1*N — double acting, single rod, non-lube
The most widely specified CS1 configuration. Factory pre-lubricated — no line lubricator required. Double acting, single rod. Bore sizes ø125–ø300mm, strokes to 2400mm, seven mounting styles. The "D" prefix (CDS1) indicates built-in piston magnet for auto switch use. Specify CDS1 for any application where position sensing is required or may be added in the future.
C(D)S1 — double acting, single rod, lube type
Lube-type variant requiring an oil lubricator in the compressed air supply. Same bore range, stroke range, and mounting options as the non-lube version. Specified when a central lubrication system is already in place, or when the application benefits from active lubrication for extended service intervals in high-cycle duty.
C(D)S1W*N — double acting, double rod, non-lube
Double rod variant for applications requiring thrust from both ends of the cylinder, symmetric load attachment, or where the second rod is used as a precision stop or position reference. Bore sizes ø125–ø300mm, strokes up to 1200mm. Available in both lube (CS1W) and non-lube (CS1W*N) configurations.
C(D)S1*H — air-hydro, single rod
The air-hydro CS1 variant uses an air-to-hydraulic booster to convert standard compressed air pressure into higher effective hydraulic pressure at the cylinder, enabling controlled, slow-speed, high-force output without a full hydraulic power unit. Suited for press-fitting, clinching, forming, and other force-intensive operations where pneumatic speed control alone is insufficient and a full hydraulic system is not justified.
CS1 low friction variant
Low friction version for applications requiring smooth motion at low operating pressures or where minimal seal drag is critical — precision positioning, low-force clamping, and applications where standard seal friction causes inconsistent actuation. Available in bore sizes ø125–ø160mm with strokes up to 1600mm.
CS1 accessories — knuckle joints, clevis pins, rod end nuts
SMC CS1 series rod end accessories are sized by bore to match the cylinder's rod thread and pin diameter. The I-type single knuckle joint (clevis-rod connection) and Y-type double knuckle joint are used to connect the piston rod to a pivoting load without transmitting bending moment into the cylinder rod. Rod end nuts and clevis/knuckle pins are available individually for maintenance and replacement.
How to read a CS1 part number
Example: CDS1FN140TN-500-A93L
C = cylinder; D = built-in magnet; S1 = CS1 series; F = mounting style (F = front flange); N = non-lube; 140 = ø140mm bore; TN = rod end thread type; 500 = 500mm stroke; A93L = auto switch type and lead wire length. The lubrication designation appears immediately after the mounting letter: no letter = lube type; N = non-lube; H = air-hydro.
CS1 large-bore cylinder applications
The CS1's large bore range makes it the standard choice when pneumatic thrust requirements exceed what compact or medium-duty cylinders can deliver. Common applications include heavy-load clamping and pressing in automotive body and powertrain assembly, long-stroke material transfer and indexing in steel and metal fabrication, high-force gate and door actuation in industrial furnace and kiln operations, pneumatic press applications in plastics and rubber molding, and long-stroke positioning in paper, film, and web handling machinery. The air-hydro CS1H variant is specifically used in press-fit, clinch, and staking operations where precise force control at low speed is required.