This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X50CB, 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 SI40X50CB
The AirTAC Airtac SI40 Standard Cylinder SI40X50CB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 50mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X50CB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke50 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X50CB
- 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 SI40X50CB
The AirTAC SI40X50CB is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore, 50 mm stroke, and CB clevis mounting. It delivers 628 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X50CB, a direct replacement retaining the exact ISO 15552 mounting interface, M12x1.25 rod thread, and 27 mm cushions.
The SAI upgrade features a refined piston seal using two Y-shaped one-way elements for lower start-up pressure and longer life. For load holding, note that a standard cylinder drifts without live air; the cushions only decelerate. Use the SAIL or BSAI lock variants if needed. Since this SKU lacks the -S magnet, it cannot accept CS1-B/DS1-B sensors.
Airtac SI40 Standard Cylinder SI40X50CB Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X50CB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X50CB |
| Bore size | Ø40 mm |
| Stroke | 50 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 SAI40X50CB 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 SAI40X50CB 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 SI40X50CB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×50 | 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 SI40X50CB Is Used
Short-Stroke Clamping
Ideal for securing medium components in machining fixtures, utilizing the 628 N push force over a compact 50 mm travel distance.
Package Diverting
Drives a 32 kg vertical lift gate or routing arm on a packaging line, offering fast 30-800 mm/s actuation via the CB clevis.
Pallet Stopper Arms
Functions as a pneumatic stop for palletized goods on roller conveyors, safely absorbing impact using the 27 mm adjustable cushions.
Replacing the Airtac SI40 Standard Cylinder SI40X50CB with the SAI40X50CB
To replace the discontinued SI40X50CB, order the SAI40X50CB. Verify your ISO 15552 CB clevis mount, G1/4 port threads (PT/G/NPT), and 50 mm stroke. Because this specific SKU has no -S suffix, it lacks a magnet and cannot support position sensing; if switches are required, select an SAI40X50CBS and use current AirTAC sensors. Sizing checks: the 40 mm bore yields 628 N push at 0.5 MPa, so if undersized, the neighboring 50 mm bore provides 982 N. For applications needing mid-stroke holding, remember the air cushion only decelerates; add a pilot check valve or choose the SAIL lock variant to prevent drift on air loss.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X50CB
- ✓ 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 SI40X50CB FAQ
Yes, the SI40X50CB is discontinued. The direct replacement is the SAI40X50CB. It shares the identical ISO 15552 CB mounting interface, 40 mm bore, 50 mm stroke, 628 N force, and G1/4 port, fitting existing fixtures perfectly while adding an upgraded piston seal.
The 40 mm bore features a G1/4 air port and M12x1.25 rod thread. Force output is 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, with a theoretical maximum of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X50CB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X50CB replacement — usually within 7-8 hours.