This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X400SLB, 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 SI40 Standard Cylinder SI40X400SLB
The AirTAC Airtac SI40 Standard Cylinder SI40X400SLB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 400mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X400SLB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke400 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X400SLB
- 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 SI40 Standard Cylinder SI40X400SLB
The AirTAC SI40X400SLB is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 400mm stroke. Delivering 628 N push force at 0.5 MPa via a G1/4 port, it is replaced by the SAI40X400SLB. This direct successor shares the exact same ISO 15552 mounting interface, bore, stroke, output force, and LB foot mounting accessories.
The SAI upgrade features a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces lock and valve variants absent in the SI line, such as the SAIL air-released lock, BSAI clamp-lock, and SAIF integrated 4M valve.
Airtac SI40 Standard Cylinder SI40X400SLB Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X400SLB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X400SLB |
| Bore size | Ø40 mm |
| Stroke | 400 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 SAI40X400SLB 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 SAI40X400SLB produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI40 Standard Cylinder SI40X400SLB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×400 | 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 SI40 Standard Cylinder SI40X400SLB Is Used
Material Diversion
Drives sorting gates on packaging lines, utilizing the 628 N push force to reliably redirect 32 kg product loads at speed.
Pallet Handling
Actuates 400mm stroke lifting arms for pallet positioning, requiring external guides to manage rod bending during lateral transfers.
Vertical Pressing
Applies downward clamping pressure in light assembly fixtures, needing a pilot check valve to hold loads securely without live air.
Replacing the Airtac SI40 Standard Cylinder SI40X400SLB with the SAI40X400SLB
To replace the SI40X400SLB, order the SAI40X400SLB. Confirm the ISO 15552 mounting interface, 40mm bore, 400mm stroke, G1/4 port (PT/G/NPT thread options), LB foot mount, and the -S magnet for CS1-B/DS1-B sensors. If sizing up, the 50mm bore offers 982 N push at 0.5 MPa; sizing down to 32mm yields 402 N. For this 400mm stroke, use external guides to prevent rod bending and side-load wear. A plain cylinder drifts on air loss—the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X400SLB
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI40 Standard Cylinder SI40X400SLB FAQ
Yes, the AirTAC SI40X400SLB is discontinued. The direct replacement is the SAI40X400SLB. It shares the identical ISO 15552 mounting interface, 40mm bore, 400mm stroke, output force, G1/4 port, and LB foot mount, fitting directly into existing fixtures.
This double-acting cylinder features a G1/4 port. The force ratings are: 628 N push and 528 N pull at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N push at 0.9 MPa, and a theoretical maximum of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X400SLB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X400SLB replacement — usually within 7-8 hours.