This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X500LB, 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 SI40X500LB
The AirTAC Airtac SI40 Standard Cylinder SI40X500LB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 500mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X500LB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke500 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X500LB
- 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 SI40X500LB
The AirTAC SI40X500LB is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 500 mm stroke. Delivering 628 N push force at 0.5 MPa through a G1/4 port, it is replaced by the SAI40X500LB. This direct upgrade matches the exact LB foot mount, M12x1.25 rod thread and dimensions.
The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure. This no-magnet SKU cannot accept a sensor; legacy CS1-B/DS1-B switches required the -S option. Viton H seals raise operating temps to 150 C.
Airtac SI40 Standard Cylinder SI40X500LB Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X500LB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X500LB |
| Bore size | Ø40 mm |
| Stroke | 500 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 SAI40X500LB 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 SAI40X500LB 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 SI40X500LB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×500 | 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 SI40X500LB Is Used
Long-Stroke Diversion
Pushes packages across a 500 mm transfer gap with 628 N force at 0.5 MPa, requiring external guides to absorb side loads.
Pallet Stopper Gate
Acts as a pneumatic stop on a LB foot-mounted pallet line, safely decelerating loads via its 27 mm adjustable air cushions.
Replacing the Airtac SI40 Standard Cylinder SI40X500LB with the SAI40X500LB
To replace the SI40X500LB, order the SAI40X500LB. Verify the ISO 15552 interface, 40 mm bore, 500 mm stroke, G1/4 port (PT/G/NPT), and LB foot mounting accessory. Because this SKU lacks the -S magnet, it cannot support position sensing. If sizing up, the 50 mm bore yields 982 N push at 0.5 MPa; if sizing down, the 32 mm bore provides 402 N. For this 500 mm stroke, use external guides to prevent rod bending and side-load damage. Note that a plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X500LB
- ✓ 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 SI40X500LB FAQ
Yes, the SI40X500LB is discontinued. The direct replacement is the SAI40X500LB. It shares the same ISO 15552 mounting interface, 40 mm bore, 500 mm stroke, G1/4 port, and LB foot mount, fitting existing fixtures perfectly.
This double-acting cylinder features a G1/4 port and M12x1.25 rod thread. It delivers 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 max of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X500LB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X500LB replacement — usually within 7-8 hours.