This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X1800, 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 SI40 Standard Cylinder SI40X1800
The AirTAC Airtac SI40 Standard Cylinder SI40X1800 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 1800mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X1800, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke1800 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X1800
- 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 SI40 Standard Cylinder SI40X1800
The AirTAC SI40X1800 is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 1800 mm stroke. It delivers 628 N push force at 0.5 MPa through a G1/4 port. Because 1800 mm exceeds the 1200 mm standard maximum for this bore, it is a non-standard, made-to-order length. The direct replacement is the SAI40X1800, which shares the exact ISO 15552 mounting interface, M12x1.25 rod thread, and 27 mm cushions.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. For sensing, note this specific SI SKU lacks a magnet and cannot accept a switch. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI40 Standard Cylinder SI40X1800 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X1800 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X1800 |
| Bore size | Ø40 mm |
| Stroke | 1800 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| 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, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI40X1800 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The SAI40X1800 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI40 Standard Cylinder SI40X1800
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×1800 | 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 SI40 Standard Cylinder SI40X1800 Is Used
Extended Transfer Push
Pushes workpieces between distant conveyor stations over a 1800 mm span, utilizing the 628 N push force at 0.5 MPa to move moderate loads reliably.
Long-Reach Material Gate
Actuates a far-reaching diverter or sorting gate in a distribution hub, requiring external guides to support the extended rod length safely.
Replacing the Airtac SI40 Standard Cylinder SI40X1800 with the SAI40X1800
To replace the SI40X1800, order the SAI40X1800. Confirm your ISO 15552 mounting accessory (LB, FA, CA, TC) and port thread (PT, G, or NPT) match. This 1800 mm stroke exceeds the 1200 mm standard maximum, so expect a non-standard, made-to-order part. At this length, side-load and rod-bending risks are high; use an external guide to prevent premature wear. If sizing down, a 32 mm bore yields 402 N push at 0.5 MPa; sizing up to 50 mm provides 982 N. This SKU lacks a magnet, so it cannot take a CS1-B/DS1-B sensor. For load holding on air loss, the cushion only decelerates; use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X1800
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI40 Standard Cylinder SI40X1800 FAQ
Yes, the SI40X1800 is discontinued. The direct replacement is the SAI40X1800. It shares the same ISO 15552 mounting interface, 40 mm bore, 1800 mm stroke, 628 N force, and G1/4 port, fitting directly into your existing fixtures.
This double-acting cylinder uses a G1/4 air port. It generates 628 N push and 528 N pull at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N push at 0.9 MPa, and a theoretical maximum of 128 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X1800
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X1800 replacement — usually within 7-8 hours.