This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX5S, 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 SI125 Standard Cylinder SI125BX5S
The AirTAC SI125 Standard Cylinder SI125BX5S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 5mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX5S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke5 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX5S
- 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 SI125 Standard Cylinder SI125BX5S
The AirTAC SI125BX5S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 5 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is SAI125BX5S, featuring a SUS304 stainless rod and matching ISO 15552 mounting interface.
This SAI upgrade uses two Y-shaped piston seals for low start-up pressure. The -S magnet pairs with CS1-B/DS1-B sensors, while SAIL/BSAI lock variants handle load holding.
Airtac SI125 Standard Cylinder SI125BX5S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX5S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX5S |
| Bore size | Ø125 mm |
| Stroke | 5 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI125BX5S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAI125BX5S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125BX5S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×5 | 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 SI125 Standard Cylinder SI125BX5S Is Used
Short-Stroke Clamping
Ideal for high-force 5 mm clamping of heavy steel plates in machining fixtures, utilizing the 6136 N push capacity.
Heavy Duty Pressing
Performs brief, intense pressing operations for industrial component seating, safely handling a 3682 N working load.
Corrosive Ejecting
The SUS304 stainless rod excels in moist or washdown environments, ejecting dense parts with reliable 5734 N pull force.
Replacing the Airtac SI125 Standard Cylinder SI125BX5S with the SAI125BX5S
To replace the SI125BX5S, order SAI125BX5S to keep the exact 125 mm bore, 5 mm stroke, G1/2 port, and ISO 15552 mounting. The -B suffix means SUS304 rod; the -S means magnet for CS1-B/DS1-B switches. For higher force, the 160 mm bore yields 10053 N push @0.5 MPa; for less, the 100 mm bore gives 3927 N. Remember, a plain cylinder drifts on air loss—the cushion only decelerates. Use SAIL or BSAI lock variants, or an external pilot check valve, to hold loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX5S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125BX5S FAQ
Yes, the SI125BX5S is discontinued. The direct replacement is the SAI125BX5S. It features the same ISO 15552 mounting interface, 125 mm bore, 5 mm stroke, G1/2 port, and SUS304 rod. You simply order the SAI equivalent for your existing fixtures.
The 125 mm bore uses a G1/2 port. It generates 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a theoretical max of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX5S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX5S replacement — usually within 7-8 hours.