This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAIJ125X400-75S, 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 SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S
The AirTAC SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 400mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAIJ125X400-75S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke400 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAIJ125X400-75S
- 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 SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S
The AirTAC SIJ125X400-75S is a double-acting double-rod ISO 15552 adjustable-stroke cylinder, now discontinued and superseded by the direct replacement SAIJ125X400-75S. It features a 125 mm bore, G1/2 port, M27x2 rod thread, and a 400 mm nominal stroke. An external stop screw lets you trim the extend stroke by up to 75 mm on-site, yielding a usable extend range of 325-400 mm to fine-tune end positions without machining. The stop sets the end position and is not a load lock; use an external rod lock or SAIL/BSAI variant for held loads.
The SAIJ replacement retains the exact interface, cushion, and force, but upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life. The -S suffix denotes a built-in piston magnet for legacy CS1-B/DS1-B switches.
Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S Technical Specifications
| Model | Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAIJ125X400-75S |
| Bore size | Ø125 mm |
| Stroke | 400 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 SAIJ125X400-75S 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 SAIJ125X400-75S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×400 | 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 SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S Is Used
Press Fit Tuning
Adjustable end-position for press fits, allowing operators to dial in a precise 325-400 mm extend stroke on-site without swapping cylinders.
Variable Length Diverter
Pneumatic diverter gates requiring field stroke tuning to accommodate changing package sizes on the fly.
Adjustable Stop Positioning
Pallet handling stop gates where the extend stroke must be trimmed by up to 75 mm to adapt to different pallet footprints.
Replacing the Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S with the SAIJ125X400-75S
Choose the 75 mm adjust window if your end-position tolerance requires trimming the 400 mm extend stroke down to 325 mm on-site; this avoids machining a custom fixed-stroke unit. Mounting options include Basic, FA, LB, and TC brackets. The -S suffix provides a piston magnet for legacy CS1-B/DS1-B sensors (current AirTAC switches are used on the SAIJ). Because the 400 mm stroke exceeds 300 mm, verify side-load limits and use external guides to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAIJ125X400-75S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-75S FAQ
Yes, the AirTAC SIJ125X400-75S is discontinued. The direct replacement is the SAIJ125X400-75S, which shares the same ISO 15552 interface, 125 mm bore, 400 mm stroke, 75 mm adjust window, G1/2 port, and mounting options. The SAIJ also features an upgraded two Y-shaped one-way piston seal for longer life.
The external stop screw provides a 75 mm adjust window, allowing the 400 mm extend stroke to be shortened to 325 mm on-site. The stop sets end position only; it is not a load lock.
Related AirTAC SAI Cylinders
Request a Quote for the SAIJ125X400-75S
Send us the quantity and destination. We confirm price, stock and lead time on the SAIJ125X400-75S replacement — usually within 7-8 hours.