This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX40, 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 SI50AX40
The AirTAC SI50 Standard Cylinder SI50AX40 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 40mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX40, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke40 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX40
- 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 SI50AX40
The AirTAC SI50AX40 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 40mm stroke. It delivers 982N push and 825N pull at 0.5MPa through a G1/4 port. The direct replacement is the SAI50AX40, matching the exact bore, stroke, force, port and ISO 15552 mounting interface for existing fixtures.
This SKU features a SUS420J2 stainless piston rod for corrosion resistance but lacks a magnet, so it cannot accept a CS1-B/DS1-B sensor. The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure.
Airtac SI50 Standard Cylinder SI50AX40 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX40 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX40 |
| Bore size | Ø50 mm |
| Stroke | 40 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 SAI50AX40 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 SAI50AX40 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 SI50AX40
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×40 | 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 SI50AX40 Is Used
Short-Stroke Clamping
Applies 982N of clamping force at 0.5MPa for securing steel workpieces during machining, utilizing the SUS420J2 rod in humid shop environments.
Ejector Mechanism
Provides rapid part ejection from molds with a 40mm stroke, operating at speeds up to 800mm/s without needing position feedback.
Replacing the Airtac SI50 Standard Cylinder SI50AX40 with the SAI50AX40
To replace the SI50AX40, order the SAI50AX40 and verify your ISO 15552 mounting interface, G1/4 port threads (PT/G/NPT) and accessory type. Because this specific SKU lacks the -S magnet, it cannot support position sensing; you must add the S suffix to the SAI order if you need current AirTAC switches. For sizing down, a 40mm bore offers 628N push at 0.5MPa; sizing up to 63mm provides 1559N. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for held loads. The 40mm stroke is short, so rod-bending side loads are minimal, but ensure correct alignment.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX40
- ✓ 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 SI50AX40 FAQ
Yes, the AirTAC SI50AX40 is discontinued. The direct replacement is the SAI50AX40. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 40mm stroke, 982N force at 0.5MPa, G1/4 port and mounting interface.
The 50mm bore features a G1/4 air port and M16x1.5 rod thread. It generates 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical maximum of 200kgf at 1.0MPa.
Request a Quote for the SAI50AX40
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX40 replacement — usually within 7-8 hours.