This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAIJ125X400-20, 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 SIJ125X400-20
The AirTAC SIJ125 Double Rod Adjustable Cylinder SIJ125X400-20 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 SAIJ125X400-20, 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 → SAIJ125X400-20
- 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 SIJ125X400-20
The AirTAC SIJ125X400-20 is a double-acting, double-rod ISO 15552 adjustable-stroke cylinder. An external stop screw lets you trim the extend stroke by up to 20 mm on-site, giving a usable 380-400 mm window from the 400 mm nominal maximum. This SIJ model is DISCONTINUED; the direct replacement is the SAIJ125X400-20, sharing the same ISO 15552 mounting interface, force, and adjust window.
The SAIJ upgrade introduces a two-piece Y-shaped one-way piston seal for lower start-up pressure and longer life. Note this SKU lacks a magnet (-S) and cannot take a switch. The stop screw sets end position only; it is not a lock. For load holding on air loss, use an external rod lock or SAIL/BSAI variant.
Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-20 Technical Specifications
| Model | Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-20 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAIJ125X400-20 |
| 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 SAIJ125X400-20 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 SAIJ125X400-20 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 SIJ125X400-20
| 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 SIJ125X400-20 Is Used
Press Fit Tuning
Allows on-site extend stroke trimming by up to 20 mm to set precise 380-400 mm press endpoints for inserting large bearings without re-machining hard stops.
Pallet Positioning
Adjusts the extend endpoint on-site to accommodate slight variations in pallet length, ensuring exact alignment at a transfer station.
Packaging Flap Folding
Fine-tunes the extend stroke to adapt to different carton depths, preventing crushing while securely folding heavy packaging flaps.
Replacing the Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X400-20 with the SAIJ125X400-20
To replace the discontinued SIJ125X400-20, order the direct replacement SAIJ125X400-20, matching the 125 mm bore, 400 mm stroke, 20 mm adjust window, and G1/2 port. Choose the 20 mm adjust window if you need precise 380-400 mm extend endpoint tuning. Reuse FA, LB, or TC ISO 15552 mounts directly. Because this SKU has no -S magnet, it cannot support legacy CS1-B/DS1-B sensors. For the 400 mm stroke, use external guides to prevent rod bending and manage side loads. The stop screw sets position but does not lock; for held loads, specify a SAIL or BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAIJ125X400-20
- ✓ 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 SIJ125X400-20 FAQ
Yes, the SIJ125X400-20 is discontinued.
The external stop screw provides a 20 mm adjust window, allowing you to trim the extend stroke from 400 mm down to 380 mm. The stop sets end position and is not a load lock.
Related AirTAC SAI Cylinders
Request a Quote for the SAIJ125X400-20
Send us the quantity and destination. We confirm price, stock and lead time on the SAIJ125X400-20 replacement — usually within 7-8 hours.