This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X650SH, 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 SI50X650SH
The AirTAC SI50 Standard Cylinder SI50X650SH is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 650mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X650SH, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke650 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X650SH
- 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 SI50X650SH
The AirTAC SI50X650SH is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 650 mm stroke, delivering 982 N push force at 0.5 MPa. The direct replacement is the SAI50X650SH, matching the exact bore, stroke, G1/4 port, M16x1.5 rod thread and ISO 15552 mounting interface. The SAI upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life. This -H variant specifies a Viton FKM seal for 0-150 C high-temperature environments.
With the -S magnet, this cylinder supports legacy CS1-B/DS1-B switches (the SAI uses current AirTAC switches). Note that a standard cylinder does not hold load without live air; the cushion only decelerates. For load holding, consider the SAIL lock or BSAI clamp-lock variants.
Airtac SI50 Standard Cylinder SI50X650SH Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X650SH |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X650SH |
| Bore size | Ø50 mm |
| Stroke | 650 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 SAI50X650SH 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 SAI50X650SH 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 SI50X650SH
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×650 | 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 SI50X650SH Is Used
High-Temp Diverting
Actuating diverters or sorting gates on hot material conveyors where the Viton H seal survives 0-150 C ambient heat without degrading.
Elevating Platforms
Raising light pallets or fixtures up to 650 mm; external guide rails must support the load to prevent rod bending during vertical travel.
Long-Reach Transfer
Pushing components between machining stations over a 650 mm gap, relying on the adjustable 30 mm air cushions to decelerate at stroke ends.
Replacing the Airtac SI50 Standard Cylinder SI50X650SH with the SAI50X650SH
To replace the SI50X650SH, order the SAI50X650SH. Verify the ISO 15552 mounting interface, 50 mm bore, 650 mm stroke, G1/4 port, M16x1.5 thread, Viton H high-temp seal, and the -S magnet for position sensing. Sizing both ways: the neighbouring 40 mm bore yields 628 N push at 0.5 MPa, while the 63 mm bore yields 1559 N. At 0.7 MPa this 50 mm bore generates 1374 N. Because the 650 mm stroke exceeds 300 mm, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss—the cushion only decelerates—so for suspended loads use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X650SH
- ✓ 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 SI50X650SH FAQ
Yes, the SI50X650SH is discontinued. The direct replacement is the SAI50X650SH. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 650 mm stroke, output force, G1/4 port, and mounting accessories. The SAI simply upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life.
The 50 mm bore features a G1/4 air port and a 20 mm rod. It generates 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and 1767 N push at 0.9 MPa. The theoretical maximum force is 200 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X650SH
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X650SH replacement — usually within 7-8 hours.