This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X1290S, 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 SI50X1290S
The AirTAC SI50 Standard Cylinder SI50X1290S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 1290mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X1290S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke1290 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X1290S
- 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 SI50X1290S
The AirTAC SI50X1290S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 1290 mm stroke. As this stroke exceeds the 1200 mm standard maximum for this bore, it was produced as a non-standard made-to-order unit. It delivers a push force of 982 N at 0.5 MPa (1374 N at 0.7 MPa) and uses a G1/4 air port. The direct replacement is the SAI50X1290S, which shares the exact ISO 15552 mounting interface, bore, stroke, force and port size for seamless fixture integration.
The SAI upgrade features a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The original SI-S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family uses current AirTAC switches. The SAI line also introduces SAIL, SAIF and BSAI lock variants unavailable in the SI series.
Airtac SI50 Standard Cylinder SI50X1290S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X1290S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X1290S |
| Bore size | Ø50 mm |
| Stroke | 1290 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 SAI50X1290S 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 SAI50X1290S 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 SI50X1290S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×1290 | 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 SI50X1290S Is Used
Long-Stroke Material Transfer
Moves products between distant workstations on a packaging line, utilizing the 1290 mm reach to bridge wide machine gaps.
Extended Lowering Press
Lowers heavy fixtures over a long descent path, relying on the adjustable 30 mm air cushions to decelerate near stroke end.
Replacing the Airtac SI50 Standard Cylinder SI50X1290S with the SAI50X1290S
To replace the discontinued SI50X1290S, order the SAI50X1290S. Confirm the ISO 15552 mounting interface (LB, FA, FB, CA, CB, TC), the G1/4 port, and the M16x1.5 rod thread. Because the 1290 mm stroke exceeds the 1200 mm standard maximum, expect a made-to-order lead time. At 0.5 MPa this 50 mm bore generates 982 N push and 825 N pull; if sizing both ways, the neighbouring 40 mm bore yields 628 N push, while the 63 mm bore provides 1559 N. For this long 1290 mm stroke, use external guides to prevent rod bending and side-load damage. 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 variant. The -S magnet works with legacy CS1-B/DS1-B switches; the SAI replacement uses current AirTAC sensors.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X1290S
- ✓ 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 SI50X1290S FAQ
Yes, the SI50X1290S is discontinued. The direct replacement is the SAI50X1290S. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 1290 mm stroke, G1/4 port, and mounting interface. The SAI features an upgraded two Y-shaped element piston seal for longer life.
This double-acting cylinder delivers a push force of 982 N and a pull force of 825 N at 0.5 MPa. At 0.7 MPa the push force is 1374 N, and the theoretical maximum is 200 kgf at 1.0 MPa. Operating pressure is 0.15-1.0 MPa, speed is 30-800 mm/s, and it uses a G1/4 port with a 30 mm adjustable cushion.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X1290S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X1290S replacement — usually within 7-8 hours.