The AirTAC Airtac SCJ40 Standard Cylinder SCJ40X70-20S is a genuine double-acting SINGLE-ROD air cylinder with a rear-cap ADJUSTING SCREW: the stroke end is field-adjustable within a 20 mm range without swapping the cylinder. Ø40mm bore, 70mm nominal stroke, PT1/4 ports and adjustable end cushioning.
The SCJ40X70-20S is a double-acting, single-rod pneumatic cylinder that puts fine stroke-end tuning directly on the machine. Its rear-cap adjusting screw provides a 20 mm adjustment range, letting you dial in the exact stopping position without swapping the cylinder or adding external hard stops. With a 16 mm piston rod and M12x1.25 rod thread, it delivers 628 N of push force at 0.5 MPa, making it a capable mid-bore actuator for tasks that need a precise, repeatable end point.
This model includes a built-in magnet (-S), so standard CMSG, DMSG, or EMSG reed and solid-state sensors clamp directly onto the tie-rod barrel for clean, reliable end-of-stroke sensing. The cylinder body length (A dimension) is 185 mm, and the adjustable air cushion decelerates the piston smoothly at both ends. It operates on filtered air from 0.15 to 1.0 MPa across a standard temperature range of -20 to +70 °C with the default TPU seals.
| Model | Airtac SCJ40 Standard Cylinder SCJ40X70-20S |
|---|---|
| Series | SCJ adjustable-stroke tie-rod cylinder |
| Bore size | Ø40 mm |
| Nominal stroke | 70 mm |
| Stroke adjustment | Up to 20 mm (rear adjusting screw) |
| Acting type | Double acting (single rod) |
| Port size | PT1/4 |
| Rod thread | M12×1.25 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Adjustable, 21 mm |
| Max stroke | Up to 1200 mm |
Specifications follow the official AirTAC SCJ (adjustable-stroke) datasheet. The rear adjusting screw sets the stroke end position; force is the same as the equivalent single-rod SC bore. Confirm against the product label before installation. Thread options: PT (standard) / G.
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
SCJ is single-rod, so force matches the equivalent SC bore: push uses the full bore area, pull subtracts the rod area. Actual usable force is lower than theoretical due to friction and back-pressure; size with a safety margin.
| SCJ | Adjustable-stroke tie-rod cylinder series. |
|---|---|
| 40 | Bore size in mm. |
| ×70 | Nominal (maximum) stroke length in mm. |
| -20 | Adjustable-stroke range in mm (options 10/20/30/40/50/75/100). |
| -S | Optional built-in magnet for sensor position sensing. |
Related types: SC (single rod, fixed stroke), SCD (double rod), SCT (multi-position). SCJ mounting: Basic, FA, LB, TC, TCM1. Seals: TPU standard / H = Viton / N = NBR. Thread: blank = PT, G = G thread.
Fine-tune the stroke end during machine commissioning without removing the cylinder. The 20 mm screw adjustment lets technicians quickly dial in the exact stop position for grippers, pushers, or clamps.
Adjust the stroke end to match different product sizes on packaging or sorting lines. The built-in magnet sends a clean sensor signal at the new stroke end, simplifying recipe-driven changeovers.
Compensate for tooling or pad wear over time by advancing the stroke end with the rear screw. This keeps a consistent pressing or clamping depth without reprogramming the machine controller.
Choose this 40 mm bore when your application needs more force than the 32 mm SCJ (402 N push at 0.5 MPa) but does not require the 982 N push of the 50 mm model. The 20 mm adjustment range is ideal for commissioning trials and format changeovers where the stroke end must be tweaked after installation. If your stroke is fixed and never needs field adjustment, a standard SC40 fixed-stroke cylinder is a simpler, more cost-effective alternative. For a direct replacement, match the 40 mm bore, 70 mm nominal stroke, 20 mm adjust range, PT port thread, basic mounting, and the -S magnet option. This cylinder is not designed to hold a load without live air pressure; if the load must remain stationary when air is exhausted, add an external rod lock or pilot-operated check valve.
Adjustable-stroke checklist
At 0.5 MPa, the push force is 628 N and the pull force is 528 N. The push force is higher because the single rod reduces the piston area on the return side. At the maximum operating pressure of 0.9 MPa, the push force reaches 1130 N.
Yes, if you need the ability to adjust the stroke end. The SCJ40X70-20S has the same bore, rod diameter, and port size as an SC40, but the rear adjusting screw adds 20 mm of stroke-end adjustment. Ensure your mounting and sensor setup accommodates the slightly longer SCJ body length of 185 mm.
Genuine AirTAC parts produced by AirTAC factory.
Covers non-human-caused product damage.
Standard models usually ship in 3-4 days.
Most inquiries answered within 7-8 hours.
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.