This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAID40X250, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAI replacement keeps the same ISO 15552 mounting interface, bore, stroke, output force and accessories, so it drops straight into existing fixtures. It is the current-production version of this cylinder with an upgraded piston seal.
Airtac SID Series Double-Rod Cylinder SID40X250
The AirTAC Airtac SID Series Double-Rod Cylinder SID40X250 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 250mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAID40X250, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke250 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAID40X250
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac SID Series Double-Rod Cylinder SID40X250
The AirTAC SID40X250 is a double-acting, double-rod ISO 15552 cylinder where a rod exits both ends, yielding equal push and pull force of 528 N at 0.5 MPa. The bore is 40 mm, the port is G1/4, and the rod thread is M12x1.25. This SID model is discontinued; the direct replacement is the SAID40X250, which reuses the exact ISO 15552 mounting interface, bore, stroke, and port. The SAI family upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life.
Because the second rod occupies the rear chamber, both faces use the rod-side area, making force equal both ways. This non-magnetic SKU cannot take a sensor. A plain cylinder drifts on air loss; the 27 mm adjustable cushions only decelerate near stroke ends, so use an external rod lock or SAIL/BSAI variant for held loads.
Airtac SID Series Double-Rod Cylinder SID40X250 Technical Specifications
| Model | Airtac SID Series Double-Rod Cylinder SID40X250 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAID40X250 |
| Bore size | Ø40 mm |
| Stroke | 250 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| 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, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAID40X250 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The SAID40X250 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SID Series Double-Rod Cylinder SID40X250
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×250 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SI-family variants: SID (double rod), SIJ (adjustable stroke) — each maps to its SAI equivalent (SID→SAID, SIJ→SAIJ). Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B).
Where the Airtac SID Series Double-Rod Cylinder SID40X250 Is Used
Inline Transfer Pusher
Drives a double-sided pusher head on a conveyor line, using the equal both-ways force to index products forward and return the arm without speed variation.
Dual-Tool Machining Slide
Mounts a cutting tool on the front rod and a secondary deburring tool on the rear rod, allowing one cylinder to perform two sequential operations.
Anti-Rotation Lift Station
Lifts a 27 kg vertical payload using the twin rods to resist torsional twist and prevent the load from binding during up and down travel.
Replacing the Airtac SID Series Double-Rod Cylinder SID40X250 with the SAID40X250
To replace the discontinued SID40X250, install the SAID40X250 directly; it matches the G1/4 port, 250 mm stroke, and ISO 15552 mounting. Size both ways by checking equal force: the 40 mm bore delivers 528 N at 0.5 MPa, so if more power is needed, step up to the 50 mm bore (825 N), or drop to the 32 mm bore (345 N) for lighter duties. Choose a double-rod cylinder when you need anti-rotation stability or must drive two tools from one piston. Mounting options include Basic, FA, LB, and TC. Since this is a non-magnetic SKU, it cannot take a switch; add the -S suffix on the SAID replacement if you need sensing. For this 250 mm stroke, side-load is minimal, but for strokes >=300 mm, ensure guide alignment to prevent rod binding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAID40X250
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SID Series Double-Rod Cylinder SID40X250 FAQ
Yes, the AirTAC SID40X250 is discontinued. The direct replacement is the SAID40X250. It shares the same ISO 15552 mounting interface, 40 mm bore, 250 mm stroke, G1/4 port, and equal both-ways force. The SAI family also adds upgraded Y-shaped piston seals and SAIL/BSAI lock variants.
Because it is a double-rod cylinder, force is equal both ways: 528 N at 0.5 MPa, 739 N at 0.7 MPa, and 950 N at 0.9 MPa. The speed range is 30-800 mm/s. The bore uses a G1/4 port, features a 27 mm adjustable cushion at each end, and operates at 0.15-1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAID40X250
Send us the quantity and destination. We confirm price, stock and lead time on the SAID40X250 replacement — usually within 7-8 hours.