This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X90, 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 SI40X90
The AirTAC Airtac SI40 Standard Cylinder SI40X90 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 90mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X90, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke90 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X90
- 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 SI40X90
The AirTAC SI40X90 is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 90 mm stroke. Delivering 628 N push force at 0.5 MPa, it features a 16 mm carbon steel rod, M12x1.25 thread, and a G1/4 port. Because this legacy series ended production, the direct replacement is the SAI40X90. It matches the exact ISO 15552 mounting interface, output force, and dimensions, dropping cleanly into existing fixtures.
The SAI upgrade introduces an upgraded piston seal using two Y-shaped one-way elements for lower start-up pressure and longer life. Note this specific SKU lacks a magnet (-S), so it cannot accept CS1-B/DS1-B sensors. For high heat, Viton H seals raise the temperature limit to 150 C.
Airtac SI40 Standard Cylinder SI40X90 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X90 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X90 |
| Bore size | Ø40 mm |
| Stroke | 90 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 SAI40X90 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 SAI40X90 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 SI40X90
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×90 | 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 SI40X90 Is Used
Component Clamping
Ideal for securing mid-weight machined parts during milling or drilling, utilizing the 628 N push force at 0.5 MPa to hold stock firmly against a fixture stop.
Package Diverting
Drives a 90 mm stroke diverter arm to redirect small to medium cartons on a packaging line, operating efficiently at speeds between 30-800 mm/s.
Light Press Fit
Applies steady pressure to seat bearings or bushings into housings on an assembly station, taking advantage of the 16 mm rod and M12x1.25 thread.
Replacing the Airtac SI40 Standard Cylinder SI40X90 with the SAI40X90
To replace the SI40X90, order the SAI40X90 and confirm your ISO 15552 mounting accessory (LB, FA, TC, etc.), 90 mm stroke, and G1/4 port (PT, G, or NPT). This non-magnetic SKU cannot take a sensor; if position detection is needed, select an SAI40X90S and use current AirTAC switches. For load holding, remember a plain cylinder drifts on air loss—the cushion only decelerates—so add an external pilot check valve or explore the SAIL lock or BSAI clamp-lock variants. If sizing both ways, a 32 mm bore yields 402 N at 0.5 MPa, while a 50 mm bore provides 982 N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X90
- ✓ 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 SI40X90 FAQ
Yes, the SI40X90 is discontinued. The direct replacement is the SAI40X90. It is dimensionally interchangeable per ISO 15552, matching the 40 mm bore, 90 mm stroke, 628 N force, G1/4 port, and mounting interface.
The G1/4 port bore delivers a push force of 628 N and pull of 528 N at 0.5 MPa. At 0.7 MPa push is 879 N, and 1130 N at 0.9 MPa. The theoretical maximum force is 128 kgf at 1.0 MPa.
Request a Quote for the SAI40X90
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X90 replacement — usually within 7-8 hours.