This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X25TC, 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 SI40X25TC
The AirTAC Airtac SI40 Standard Cylinder SI40X25TC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 25mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X25TC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke25 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X25TC
- 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 SI40X25TC
The AirTAC SI40X25TC is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 25mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X25TC, a direct upgrade retaining the exact same interface, force, and TC trunnion mount.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Note this specific SKU lacks a magnet and cannot accept a CS1-B/DS1-B sensor.
Airtac SI40 Standard Cylinder SI40X25TC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X25TC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X25TC |
| Bore size | Ø40 mm |
| Stroke | 25 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 SAI40X25TC 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 SAI40X25TC 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 SI40X25TC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×25 | 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 SI40X25TC Is Used
Short-Stroke Clamping
Ideal for holding light metal or composite parts during machining, utilizing the 628N push force and 25mm stroke for rapid, repeatable actuation.
Package Diverting
Provides compact stop-and-divert action on material handling lines, where the 32kg vertical lift capacity easily manages lightweight product routing.
Small Part Ejection
Delivers fast ejection of molded or stamped components from fixtures, benefiting from the 30-800mm/s speed range and TC trunnion pivot alignment.
Replacing the Airtac SI40 Standard Cylinder SI40X25TC with the SAI40X25TC
To replace the SI40X25TC, order the SAI40X25TC. Verify the ISO 15552 TC trunnion mounting, 40mm bore, 25mm stroke, G1/4 port, and M12x1.25 rod thread. Because this SKU has no magnet (-S), it cannot support position sensing; if detection is needed, select an SAI40X25TCS. Sizing options include stepping up to a 50mm bore for more thrust or down to a 32mm bore if 402N is sufficient. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X25TC
- ✓ 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 SI40X25TC FAQ
Yes, the SI40X25TC is discontinued. The direct replacement is the SAI40X25TC. It shares the identical ISO 15552 mounting interface, 40mm bore, 25mm stroke, G1/4 port, and output force, fitting directly into existing TC trunnion fixtures.
This 40mm bore double-acting cylinder uses a G1/4 air port. It generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X25TC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X25TC replacement — usually within 7-8 hours.