This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X70, 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 SI50X70
The AirTAC SI50 Standard Cylinder SI50X70 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 70mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X70, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke70 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X70
- 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 SI50X70
The AirTAC SI50X70 is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore and 70mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. Because this legacy unit is end-of-life, you should order the SAI50X70 direct replacement. It shares the exact ISO 15552 mounting interface, bore, stroke, output force, port size and mounting accessories, fitting existing fixtures perfectly.
The SAI upgrade introduces a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. This SKU lacks a magnet (-S), so it cannot accept a CS1-B or DS1-B sensor. For load holding, note that a plain cylinder drifts on air loss; use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Airtac SI50 Standard Cylinder SI50X70 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X70 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X70 |
| Bore size | Ø50 mm |
| Stroke | 70 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 SAI50X70 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 SAI50X70 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 SI50X70
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×70 | 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 SI50X70 Is Used
Package Diverting
Actuates diverting arms on packaging lines, using the 982N push force at 0.5MPa to push cartons smoothly onto adjacent belts.
Clamp Actuation
Provides reliable clamping pressure for light machining fixtures, utilizing the 825N pull force to hold components securely during drilling.
Stopper Gate Control
Operates pneumatic stopper gates in material handling conveyors, raising and lowering barriers to regulate pallet flow.
Replacing the Airtac SI50 Standard Cylinder SI50X70 with the SAI50X70
To replace the SI50X70, order the SAI50X70 and confirm the ISO 15552 mounting interface, 50mm bore, 70mm stroke, G1/4 port (PT/G/NPT thread options), and your mounting accessory (LB, FA, FB, CA, CB, TC). This non-magnetic SKU cannot take a sensor; if position detection is needed, select an SAI50X70S and use current AirTAC switches. For sizing both ways: dropping to a 40mm bore reduces push force to 628N at 0.5MPa, while stepping up to a 63mm bore increases it to 1559N. Remember that a plain cylinder does not hold load without live air; for secure holding, consider the SAIL air-released lock or BSAI clamp-lock variant, or add an external pilot check valve. The 70mm stroke is well below the 1200mm maximum, so no side-load guide concerns apply here.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X70
- ✓ 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 SI50X70 FAQ
Yes, the SI50X70 is discontinued. The direct replacement is the SAI50X70. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 70mm stroke, 982N force, G1/4 port, and mounting interface, so it drops directly into existing fixtures.
The 50mm bore features a G1/4 air port and an M16x1.5 rod thread. Theoretical forces are: 982N push and 825N pull at 0.5MPa; 1374N push at 0.7MPa; 1767N push at 0.9MPa; with a maximum theoretical force of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Request a Quote for the SAI50X70
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X70 replacement — usually within 7-8 hours.