This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X90S, 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 SI50X90S
The AirTAC SI50 Standard Cylinder SI50X90S 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 SAI50X90S, 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 → SAI50X90S
- 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 SI50X90S
The AirTAC SI50X90S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 90mm stroke. It delivers 982N push and 825N pull at 0.5MPa through a G1/4 port. The direct replacement is the SAI50X90S, retaining identical interface dimensions, force, and mounting fixtures.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked. This -S SKU includes a piston magnet for CS1-B/DS1-B switches.
Airtac SI50 Standard Cylinder SI50X90S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X90S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X90S |
| 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 SAI50X90S 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 SAI50X90S 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 SI50X90S
| 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 SI50X90S Is Used
Package Diversion
Actuates routing gates on packaging lines where 982N push force reliably redirects cartons up to 50kg at moderate 30-800mm/s speeds.
Clamp Actuation
Provides secure holding pressure for mid-sized machining fixtures, utilizing the 825N pull force to retract clamps quickly.
Vertical Lift Stops
Controls descent and stopping mechanisms for material handling lifts, safely managing vertical loads around 50kg.
Replacing the Airtac SI50 Standard Cylinder SI50X90S with the SAI50X90S
To replace this SI50X90S, order the SAI50X90S. Confirm the ISO 15552 mounting interface, 90mm stroke, G1/4 port (PT/G/NPT), and your mounting accessory (LB, FA, TC, etc.). The -S denotes a piston magnet for legacy CS1-B/DS1-B sensors; the SAI uses current AirTAC switches. Sizing both ways: the 50mm bore yields 982N push at 0.5MPa, while the neighboring 40mm bore offers 628N and the 63mm bore provides 1559N. A plain cylinder drifts on air loss as the cushion only decelerates; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X90S
- ✓ 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 SI50X90S FAQ
Yes, the SI50X90S is discontinued. The direct replacement is the AirTAC SAI50X90S. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 90mm stroke, G1/4 port, and mounting fixtures for a seamless upgrade.
The 50mm bore features a G1/4 air port and M16x1.5 rod thread. It delivers 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.
Request a Quote for the SAI50X90S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X90S replacement — usually within 7-8 hours.