This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X140, 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 SI50X140
The AirTAC Airtac SI50 Standard Cylinder SI50X140 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 140mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X140, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke140 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X140
- 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 SI50X140
The AirTAC SI50X140 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 140 mm stroke. It delivers a push force of 982 N and a pull force of 825 N at 0.5 MPa, utilizing a G1/4 air port and a 20 mm carbon steel piston rod with an M16x1.5 thread. AirTAC replaced this legacy unit with the SAI50X140 direct replacement, which matches the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI50X140 upgrade introduces an improved piston seal featuring two Y-shaped one-way elements for low start-up pressure and extended life. This SKU lacks the -S magnet option, meaning it cannot accept position sensors. For load holding, note that a standard cylinder drifts on air loss; the air cushion only decelerates the piston near stroke end. For secure holding, consider the SAIL or BSAI lock variants.
Airtac SI50 Standard Cylinder SI50X140 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X140 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X140 |
| Bore size | Ø50 mm |
| Stroke | 140 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 SAI50X140 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 SAI50X140 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 SI50X140
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×140 | 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 SI50X140 Is Used
Package Diversion
Actuates routing gates on packaging lines, utilizing the 982 N push force at 0.5 MPa to smoothly pivot packages weighing up to 50 kg.
Clamp Actuation
Provides reliable clamping pressure for machining fixtures, taking advantage of the adjustable 30 mm air cushions to decelerate the 140 mm stroke at cycle end.
Replacing the Airtac SI50 Standard Cylinder SI50X140 with the SAI50X140
To replace the discontinued SI50X140, order the SAI50X140. Verify your ISO 15552 mounting fixture, the 140 mm stroke, and the G1/4 port (available in PT, G, or NPT). Because this specific SKU lacks the -S magnet suffix, it cannot support CS1-B or DS1-B sensors; if position detection is required, switch to a magnet-equipped SAI model. For sizing alternatives, a neighbouring 40 mm bore yields 628 N push at 0.5 MPa, while a 63 mm bore provides 1559 N. If your application requires load holding on air loss, a plain cylinder will drift—select the SAIL air-released lock or BSAI clamp-lock variant, or install an external pilot check valve. Since the 140 mm stroke is under 300 mm, rod bending and side-load risks are minimal, but standard guide alignment is still advised.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X140
- ✓ 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 SI50X140 FAQ
Yes, the SI50X140 is discontinued. The direct replacement is the SAI50X140. It is dimensionally interchangeable per ISO 15552, matching the 50 mm bore, 140 mm stroke, 982 N force, G1/4 port, and mounting accessories, so it fits existing fixtures directly.
The 50 mm bore features a G1/4 air port and a 20 mm rod. The thrust is 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, 1767 N push at 0.9 MPa, and a theoretical maximum force of 200 kgf at 1.0 MPa.
Request a Quote for the SAI50X140
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X140 replacement — usually within 7-8 hours.