The SMC CXSM6-20 is a compact guided dual-rod pneumatic cylinder designed for applications that require accurate linear motion, improved anti-rotation performance, and a more stable load-carrying structure than a conventional single-rod air cylinder. It belongs to SMC’s CXS series, a widely used family of guided actuators built for precision handling, small-part positioning, clamping support, pick-and-place assemblies, and compact automation equipment. For engineers and maintenance buyers who need a small actuator with predictable motion and a rigid guide mechanism, the CXSM6-20 is a practical and efficient choice. Its catalog configuration is a 6 mm bore with a 20 mm stroke.
Key Specifications
| Item | Specification |
|---|---|
| Brand | SMC |
| Model | CXSM6-20 |
| Series | CXS |
| Product Type | Guided dual-rod pneumatic cylinder |
| Bore Size | 6 mm |
| Stroke | 20 mm |
| Action | Double acting |
| Operating Pressure Range | 0.15 to 0.7 MPa |
| Proof Pressure | 1.05 MPa |
| Ambient / Fluid Temperature | -10 to 60°C (non-freezing) |
| Piston Speed | 30 to 800 mm/s |
| Port Size | M5 x 0.8 |
| Approximate Dimensions | 78.5 x 16 x 37 mm |
| Product Net Weight | 0.095 kg (95 g) |
The weight value above comes from the official SMC CXS series catalog, where the CXSM 6 at 20 mm stroke is listed at 0.095 kg. Distributor data also lists the same model at 95 g, which aligns with the catalog figure.
Product Overview
The CXSM6-20 is engineered for users who need more than simple extend-and-retract motion. In many compact machines, a standard cylinder can create unwanted rotation, side-load sensitivity, or poor alignment when a tool or workpiece is mounted directly to the rod. The CXSM6-20 addresses that problem by integrating a guided structure with dual rods, which helps keep the moving platform aligned during travel. This makes the actuator suitable for light-duty precision tasks where stable motion matters more than brute force. The CXS series is built around this concept: a compact footprint combined with better load guidance and higher motion repeatability than a general-purpose rod cylinder.
Because the unit uses a 6 mm bore and 20 mm stroke, it fits well in compact automation designs where space is limited but motion accuracy still matters. The relatively short stroke is useful for small transfer motions, stopper mechanisms, part separation, sensor-trigger movements, and miniature clamping or lifting arrangements. In assembly fixtures, packaging machines, electronics handling systems, and small jigs, this size is often selected when the actuator needs to fit into a tight mechanical envelope without sacrificing guided support. The listed body dimensions of approximately 78.5 mm in length, 16 mm in width, and 37 mm in height reflect that compact design intent.
Why the Guided Design Matters
The main advantage of the CXSM6-20 is not simply that it moves; it is that it moves in a more controlled way. A dual-rod guided cylinder distributes load better and resists twisting during operation. That improves the reliability of the actuator when it is used to push, stop, position, or support small components. If a tooling plate, bracket, or gripper attachment is mounted on the moving section, the guided layout helps maintain orientation during travel. That reduces the chance of misalignment and can improve cycle consistency in repetitive machines.
This matters in real production environments. When an actuator is installed in a pick-and-place system, even a small amount of unwanted rotation can affect placement quality. When it is used as a stop cylinder in a transfer line, poor guidance can create uneven contact and wear. The CXSM6-20 is designed to reduce those problems by offering a guided, compact slide mechanism within a standard pneumatic format. SMC’s CXS series also notes that slide bearing and ball bushing bearing versions share the same dimensional concept, which supports flexible application design across the product family.
Performance Characteristics
From a performance standpoint, the CXSM6-20 offers a practical operating envelope for small automation equipment. The official CXS series specifications list a maximum operating pressure of 0.7 MPa, a minimum operating pressure of 0.15 MPa for the 6 mm bore, and a proof pressure of 1.05 MPa. The catalog also lists an ambient and fluid temperature range of -10 to 60°C when no freezing is present. These values make the cylinder suitable for typical factory compressed-air systems and standard indoor automation environments.
The catalog gives a piston speed range of 30 to 800 mm/s for the smaller bore sizes in the CXS family, including the 6 mm version. That means the CXSM6-20 can be tuned for either controlled short-stroke positioning or faster cycle motion, depending on the circuit design, flow control, load, and cushioning arrangement. The cylinder uses a rubber bumper style of cushioning in the standard specification, which is appropriate for compact strokes and moderate-speed operation.
The M5 x 0.8 port size is consistent with the compact size class of this actuator. In practice, this helps keep pneumatic plumbing small and manageable, especially in dense machine layouts. For OEM builders, that can simplify manifold routing and reduce the space required around the actuator.
Product Weight and Handling Advantage
A key point for many buyers is weight, especially when the cylinder is mounted on a moving axis or within a tightly optimized mechanism. The SMC CXSM6-20 weighs approximately 0.095 kg (95 g) in the standard catalog configuration. That low mass is a real advantage in compact assemblies because it reduces the inertia added to the machine frame or moving bracket. For designers building lightweight handling tools, sensor stations, or compact transfer units, a lighter actuator can help maintain faster cycle times and lower support-structure requirements.
It is worth noting that practical installed weight can change slightly if the cylinder is ordered with auto switches, brackets, fittings, or special options. However, the catalog figure of 95 g is the correct baseline for the standard CXSM6-20 specification.
Typical Applications
The CXSM6-20 is well suited for:
| Application Type | Typical Use |
|---|---|
| Small Parts Handling | Short guided transfer of light components |
| Positioning Stops | Controlled stopping of parts on compact feeders |
| Assembly Fixtures | Stable motion for pressing, locating, or aligning small workpieces |
| Electronics Automation | Precision travel where non-rotation is important |
| Packaging Equipment | Light-duty guided movement in compact machine sections |
| Sensor or Probe Actuation | Repeatable linear travel in short-stroke devices |
In these applications, the cylinder’s compact body, guided motion, and low weight make it especially useful where installation space is limited and repeatable linear travel is more important than long stroke length.
Final Assessment
The SMC CXSM6-20 is a compact, technically practical guided cylinder for users who need stable, non-rotating short-stroke pneumatic motion in a small package. Its combination of 6 mm bore, 20 mm stroke, double-acting operation, 0.15 to 0.7 MPa operating range, and 95 g weight makes it a strong fit for compact automation, light tooling, and precision handling equipment. If the application demands a small actuator with better guidance and load stability than a basic air cylinder, the CXSM6-20 is a solid engineering choice.
