This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X15S, 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 SI50X15S
The AirTAC Airtac SI50 Standard Cylinder SI50X15S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 15mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X15S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke15 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X15S
- 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 SI50X15S
The AirTAC SI50X15S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 15mm stroke. It delivers 982N push and 825N pull at 0.5MPa through a G1/4 port. The direct replacement is the SAI50X15S, which shares the same interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. The SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI50 Standard Cylinder SI50X15S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X15S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X15S |
| Bore size | Ø50 mm |
| Stroke | 15 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 SAI50X15S 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 SAI50X15S 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 SI50X15S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×15 | 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 SI50X15S Is Used
Short-Stroke Clamping
Ideal for holding parts in machining fixtures where a 15mm travel provides rapid, firm clamping using the 982N push force at 0.5MPa.
Package Diversion
Deployed on packaging lines to actuate short routing gates or pusher blades, moving light goods quickly within the 30-800mm/s speed range.
Ejector Mechanism
Used to eject molded or stamped components from presses, utilizing the 825N pull force at 0.5MPa for reliable retraction in tight spaces.
Replacing the Airtac SI50 Standard Cylinder SI50X15S with the SAI50X15S
To replace the SI50X15S, order the SAI50X15S keeping the 50mm bore, 15mm stroke, G1/4 port, and M16x1.5 rod thread. Confirm the ISO 15552 mounting accessory and the -S magnet for current AirTAC switches (legacy used CS1-B/DS1-B). If you need more force, the 63mm bore offers 1559N push at 0.5MPa; if less, the 40mm gives 628N. A plain cylinder drifts on air loss as the cushion only decelerates, so use a pilot check valve or the SAIL lock variant for load holding. Rod material options include carbon steel, SUS420J2, or SUS304.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X15S
- ✓ 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 SI50X15S FAQ
Yes, the AirTAC SI50X15S is discontinued. The direct replacement is the SAI50X15S. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 15mm stroke, G1/4 port, and mounting interface.
The 50mm bore uses a G1/4 port. It generates 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical max of 200kgf at 1.0MPa.
Request a Quote for the SAI50X15S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X15S replacement — usually within 7-8 hours.