This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X120H, 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 SI40X120H
The AirTAC Airtac SI40 Standard Cylinder SI40X120H is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X120H, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X120H
- 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 SI40X120H
The AirTAC SI40X120H is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 120 mm stroke. Designed with an extruded aluminum barrel and adjustable air cushions at both ends, it delivers 628 N of push force at 0.5 MPa. The direct replacement is the SAI40X120H, which matches the original G1/4 port, M12x1.25 rod thread, and ISO 15552 mounting interface for seamless fixture integration.
This specific SKU features a Viton H seal, extending the operating temperature range from -20 to +70 C up to 0-150 C for high-heat environments. Because it lacks the -S magnet suffix, it cannot accept a position sensor. The SAI upgrade introduces an advanced two-piece Y-shaped piston seal for lower start-up pressure and longer life, while expanding the family with SAIL lock, SAIF valve, and BSAI clamp-lock variants.
Airtac SI40 Standard Cylinder SI40X120H Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X120H |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X120H |
| Bore size | Ø40 mm |
| Stroke | 120 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 SAI40X120H 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 SAI40X120H 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 SI40X120H
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×120 | 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 SI40X120H Is Used
Hot-Stamping Ejector
Utilizes the Viton H high-temperature seal to reliably eject stamped parts from heated tooling up to 150 C without degrading.
Divert Arm Actuator
Provides 628 N of push force at 0.5 MPa to swing diverting gates on packaging lines, moving boxes smoothly with adjustable end cushions.
Replacing the Airtac SI40 Standard Cylinder SI40X120H with the SAI40X120H
To replace the discontinued SI40X120H, order the SAI40X120H. Verify your existing fixture's ISO 15552 mounting interface (such as LB foot or FA flange), the 40 mm bore, 120 mm stroke, and G1/4 port. Confirm your thread standard (PT, G, or NPT) and note that this non-magnetic SKU cannot support a sensor; if sensing is required, specify an SAI model with the -S magnet option for CS1-B or DS1-B switches. If your application needs to hold a load during air loss, remember that standard air cushions only decelerate the piston and do not provide braking; you will need an external pilot check valve, a rod lock, or the SAIL/BSAI lock variant. For force scaling, the neighboring 32 mm bore provides 402 N push at 0.5 MPa, while the 50 mm bore offers 982 N. If your stroke exceeds 300 mm, ensure adequate guide support to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X120H
- ✓ 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 SI40X120H FAQ
Yes, the AirTAC SI40X120H is discontinued and end-of-life. The direct replacement is the SAI40X120H. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the exact 40 mm bore, 120 mm stroke, G1/4 port, and output force to fit existing fixtures perfectly.
The 40 mm bore features a G1/4 air port and a 16 mm rod. The thrust 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. It operates at speeds between 30 and 800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X120H
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X120H replacement — usually within 7-8 hours.