This model is discontinued
AirTAC has phased out the ACP series. You can still order this code here: we ship the current replacement ACEJ12X125-40, the same code under the new prefix. The ACE replacement is a current-production ISO 21287 compact cylinder in the same bore, stroke and force class, with a matching short body and the same mounting-accessory family, so it fits the same envelope. Confirm mounting-interface dimensions against the ACE datasheet before ordering.
Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40
The AirTAC ACPJ Adjustable Compact Cylinder ACPJ12X125-40 is a double acting, double rod, adjustable stroke DIN-standard tight/compact air cylinder with a Ø12mm bore and 125mm stroke, M5×0.8 air ports and a hard-anodized aluminium body. This model is discontinued — the current-production replacement is the ACEJ12X125-40 (ISO 21287 ACE), in the same bore, stroke and force class.
- BoreØ12 mm
- Stroke125 mm
- Port sizeM5×0.8
- Acting typeDouble acting, double rod, adjustable stroke
- Rod threadM3×0.5
- StatusDiscontinued → ACEJ12X125-40
- 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 ACPJ Adjustable Compact Cylinder ACPJ12X125-40
This is a double acting compact cylinder with an adjustable extend stroke: a stop screw trims the 125 mm stroke by up to 40 mm, giving a usable range of 85-125 mm on site. At 0.5 MPa the 12 mm bore delivers 56.5 N push and 42.4 N pull; at 0.7 MPa it reaches 79.2 N push. Because the short ISO 21287-class body saves about 50% of the mounting length of an ISO 15552 profile cylinder, it slots into slim fixtures, sliding guards and pick stations where a full-length body cannot. Note the 125 mm stroke exceeds the 50 mm standard maximum for this bore, so it is a made-to-order item.
Plan around roughly 34 N of usable work at 0.5 MPa (about 60% of the rated push) and expect it to lift about 2.8 kg vertically with a 2:1 margin. The hard-anodized aluminium body carries an S45C hard-chrome rod, fixed TPU bumpers at both ends, and an M3x0.5 female rod thread. No magnet is fitted on this code; the optional -S version adds one for CMSE / DMSE switches. The ACPJ family is discontinued - the current-production drop-in is the ACEJ12X125, so confirm ISO 21287 mounting dimensions before swapping.
Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40 Technical Specifications
| Model | Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40 |
|---|---|
| Series | ACPJ DIN compact cylinder (discontinued) |
| Replacement | ACEJ12X125-40 |
| Bore size | Ø12 mm |
| Stroke | 125 mm |
| Acting type | Double acting, double rod, adjustable stroke |
| Port size | M5×0.8 |
| Rod thread | M3×0.5 |
| 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 | Fixed bumper (both ends) |
| Max standard stroke | Up to 50 mm |
Specifications follow the official AirTAC ACP datasheet (now discontinued). The ACEJ12X125-40 (ISO 21287) carries the same bore/stroke/force class; confirm mounting-interface dimensions against the ACE datasheet before installation. Rod type: female thread (blank) or male thread (B). Thread options: PT (blank) / G.
Theoretical Output Force (Ø12mm)
| Pressure | Force (both ways) |
|---|---|
| 0.5 MPa | 42 N |
| 0.7 MPa | 59 N |
| Max (@1.0 MPa) | 9 kgf |
ACPJ is double-rod: the rear rod that carries the stroke adjuster exits the rear cover, so both piston faces lose rod area. The rod-side (annular) area is used for both directions (conservative).
Model Code: Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40
| ACPJ | DIN compact cylinder (adjustable-stroke, discontinued). |
|---|---|
| 12 | Bore size in mm. |
| ×125 | Stroke length in mm. |
| -40 | Adjustable stroke window (mm the extend stroke can be shortened on site). |
| S | Optional built-in magnet for sensor position sensing (omit for no magnet). |
| B | Rod type: B = male thread; blank = female thread. |
Replacement mapping (swap P for E): ACP→ACE, ASP→ASE, ATP→ATE, ACPD→ACED, ACPJ→ACEJ. ACP-family: ACP (double acting), ASP / ATP (single acting push / pull), ACPD (double rod), ACPJ (double rod, adjustable stroke).
Where the Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40 Is Used
Small-part ejection from press dies
The 56.5 N push at 0.5 MPa clears stamped clips and gaskets off a die face, while the 40 mm window lets the setter trim the 125 mm stroke to the exact ejection distance.
Indexed slide on a compact test rig
With the optional -S magnet and CMSE / DMSE switches, the rod position is confirmed at each end of the 85-125 mm trimmed range in a bench-top leak or functional tester.
Light clamp on an electronics assembly jig
About 34 N of practical holding force secures PCB carriers during screwdriving; the short body fits under the jig crown where an ISO 15552 profile cylinder would not.
Replacing the Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40 with the ACEJ12X125-40
Size up if 56.5 N at 0.5 MPa is marginal: the 16 mm bore gives 100.5 N push and the 20 mm bore 157.1 N in the same compact family. Size down only if your stroke fits the 50 mm standard limit of the 12 mm bore. The 40 mm window suits applications needing a repeatable shorter extend stroke set once at commissioning; the stop is a mechanical end stop, not a mid-stroke lock, so the rod still drifts if air is lost. FA/FB flange and LB foot mountings bolt to the standard face, and the optional -S magnet enables CMSE / DMSE sensing. For new builds, order the ACEJ12X125 instead - same bore, stroke and force class, currently in production.
Replacement checklist
- ✓ Current-production ACE → ACEJ12X125-40
- ✓ Same bore / stroke / force class
- ✓ Confirm ISO 21287 mounting dimensions
- ✓ Port/thread type (PT / G)
- ✓ Add -S for magnet if you need sensors
Airtac ACPJ Adjustable Compact Cylinder ACPJ12X125-40 FAQ
At 0.5 MPa it pushes 56.5 N and pulls 42.4 N; at 0.7 MPa, 79.2 N push and 59.4 N pull; theoretical maximum is 11.5 kgf at 1.0 MPa. Operating range is 0.15-1.0 MPa (22-145 psi), proof 1.5 MPa (215 psi), speed 30-500 mm/s, temperature -20 to +70 C, air filtered to 40 um. Port is M5x0.8, rod thread M3x0.5 female, and the 125 mm stroke is made to order since the bore's standard maximum is 50 mm.
The -40 code is a 40 mm window: an external stop screw shortens the extend stroke anywhere within it, so you can set any usable stroke from 85 to 125 mm. It is a mechanical end stop only - it never holds a load if air is lost. The ACPJ is discontinued; the current drop-in is the ACEJ12X125 (P changed to E) in the same bore, stroke and force class. Confirm the ISO 21287 mounting dimensions before swapping, since the ACP follows the older DIN-standard footprint.
Related AirTAC ACE Cylinders
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