This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX120TC, 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 SI40BX120TC
The AirTAC Airtac SI40 Standard Cylinder SI40BX120TC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX120TC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX120TC
- 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 SI40BX120TC
The AirTAC SI40BX120TC is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 120mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI40BX120TC, matching the interface, force, and TC trunnion mount. This specific SKU uses a SUS304 stainless steel rod (-B) and lacks a magnet, meaning it cannot accept legacy CS1-B/DS1-B sensors.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note that a plain cylinder drifts on air loss; the cushion only decelerates. For held loads, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Airtac SI40 Standard Cylinder SI40BX120TC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX120TC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX120TC |
| Bore size | Ø40 mm |
| Stroke | 120 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 SAI40BX120TC 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 SAI40BX120TC 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 SI40BX120TC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×120 | 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 SI40BX120TC Is Used
Bottle Line Diversion
Routes containers on a washdown conveyor using the corrosion-resistant SUS304 rod, handling the 32kg vertical lift margin safely.
Stainless Fixture Indexing
Provides 628N push at 0.5MPa to cycle a machining fixture, relying on the TC trunnion to absorb lateral alignment stresses.
Pallet Gate Actuation
Swings a lightweight access gate on a packaging floor, using the 120mm stroke to clear the path without requiring load holding.
Replacing the Airtac SI40 Standard Cylinder SI40BX120TC with the SAI40BX120TC
To replace the SI40BX120TC, order the SAI40BX120TC. Verify the ISO 15552 TC trunnion interface, 40mm bore, 120mm stroke, G1/4 port, and SUS304 rod. Because this SKU lacks a magnet (-S), it cannot support sensing; if position detection is needed, order an SAI equivalent with the magnet option for current AirTAC switches. If sizing up or down, a 32mm bore yields 402N push at 0.5MPa, while a 50mm bore yields 982N. A plain cylinder does not hold load without live air—the cushion only decelerates. For secure holding, use a pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX120TC
- ✓ 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 SI40BX120TC FAQ
Yes, the SI40BX120TC is discontinued. The direct replacement is the SAI40BX120TC. It is a true ISO 15552 profile cylinder that matches the 40mm bore, 120mm stroke, G1/4 port, and TC trunnion mounting interface, dropping directly into existing fixtures.
The 40mm bore uses a G1/4 port. It generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum of 128kgf at 1.0MPa. The rod is 16mm with an M12x1.25 thread, and the cushion stroke is 27mm.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX120TC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX120TC replacement — usually within 7-8 hours.