This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X90, 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 SI50 Standard Cylinder SI50X90
The AirTAC Airtac SI50 Standard Cylinder SI50X90 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 90mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X90, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke90 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X90
- 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 SI50 Standard Cylinder SI50X90
The AirTAC SI50X90 is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore and 90mm stroke. It delivers 982N push force at 0.5MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50X90, a direct replacement retaining the exact mounting interface, bore, stroke, and output force.
The SAI upgrade introduces a two-piece Y-shaped piston seal for lower start-up pressure and extended life. Note this non-S SKU lacks a magnet and cannot accept CS1-B/DS1-B sensors. For load holding without live air, explore SAIL or BSAI lock variants.
Airtac SI50 Standard Cylinder SI50X90 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X90 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X90 |
| Bore size | Ø50 mm |
| Stroke | 90 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M16×1.5 |
| 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, 30 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI50X90 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø50mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 982 N | 825 N |
| 0.7 MPa | 1374 N | — |
| Max (@1.0 MPa) | 200 kgf | |
The SAI50X90 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI50 Standard Cylinder SI50X90
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | 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 SI50 Standard Cylinder SI50X90 Is Used
Package Diverting
Actuates diverting arms on packaging lines to route boxes, utilizing the 90mm stroke to push items cleanly off the main belt path.
Pallet Stops
Functions as a pneumatic stop gate in roller conveyors, holding pallets steady at 982N push force for robotic pickup operations.
Clamp Actuation
Drives medium-duty clamping fixtures in CNC machining cells, providing reliable holding force within compact workholding spaces.
Replacing the Airtac SI50 Standard Cylinder SI50X90 with the SAI50X90
To replace the SI50X90, order the SAI50X90. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), G1/4 port thread (PT/G/NPT), and 90mm stroke. Because this specific SKU lacks the -S magnet suffix, it cannot support position sensing; order an -S variant if switches are required. Sizing both ways: if downsizing, a 40mm bore yields 628N push @0.5MPa; if upsizing, a 63mm bore yields 1559N. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external pilot check valve for holding. The SAI family also offers SAIF (integrated valve) and SAIL (air-released lock) variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X90
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI50 Standard Cylinder SI50X90 FAQ
Yes, the SI50X90 is discontinued. The direct replacement is the AirTAC SAI50X90. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 90mm stroke, G1/4 port, and mounting interface, so it drops directly into existing fixtures.
The 50mm bore features a G1/4 air port and M16x1.5 rod thread. Force ratings are: 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical maximum of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Request a Quote for the SAI50X90
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X90 replacement — usually within 7-8 hours.