Collection: Camozzi Series ST Stopper Pneumatic Cylinders

Technical information & FAQs

Camozzi Series ST Stopper Pneumatic Cylinders

Camozzi Series ST stopper pneumatic cylinders are purpose-built for conveyor, pallet and workpiece-handling systems where a moving load must be stopped accurately and repeatedly. Their reinforced rod and guide arrangement is designed to resist radial loads and impact forces that would be unsuitable for many conventional compact pneumatic cylinders.

The range includes UNITOP ST31 and ISO 21287 ST32 constructions, with single-acting, double-acting, rear-spring, non-rotating and roller-rod configurations. This allows the stopper pneumatic cylinder to be selected around the actual conveyor load, stopping method and mounting arrangement rather than treating it as a generic compact actuator.

Series ST Technical Specification

Manufacturer	Camozzi Automation
Series	ST
Product Category	Stopper pneumatic cylinders
Construction Standards	ST31 = UNITOP; ST32 = ISO 21287
Bore Sizes	20, 32, 40 and 50 mm
Stroke Range	5 to 30 mm depending on model and bore
Operation	Double acting, single acting with rear spring, or double acting with rear spring
Rod Designs	Standard, female thread, non-rotating and non-rotating with roller
Position Detection	Magnetic
Cushioning	Mechanical end-stroke rubber shock absorbers
Operating Pressure	1–10 bar double acting; 2–10 bar single acting
Maximum Frequency	5 Hz for 20, 32 and 40 mm; 3 Hz for 50 mm
Mounting	Direct mounting through holes in the end caps
Profile	Anodised aluminium
Rod	Stainless steel

ST31 UNITOP or ST32 ISO 21287?

Series ST is divided into two main dimensional constructions. ST31 follows UNITOP dimensions, while ST32 follows ISO 21287. This distinction matters when replacing an existing stopper pneumatic cylinder because the surrounding conveyor or fixture may already be built around one of those mounting envelopes.

ST32 also offers the broader configuration range, including non-rotating and roller-rod versions and the 40 mm bore size.

Built to Stop Moving Pallets and Workpieces

A stopper pneumatic cylinder does a very different job from a normal actuator. Instead of simply moving a mechanism, it often has to intercept a moving pallet or workpiece and absorb the resulting radial and impact loads.

Camozzi therefore enlarges the rod and guide bushing specifically to improve resistance to shock and side loading. Series ST is especially suited to conveyor lines where workpiece carriers need to be held, released or sequenced at defined positions. :contentReference[oaicite:1]{index=1}

Standard, Non-Rotating or Roller Rod

The rod design changes how the stopper interacts with the moving load.

Version	Best Suited To
Standard	Direct stopping where a conventional rod end suits the workpiece or pallet
Non-rotating	Applications where the rod orientation must remain controlled
Non-rotating with roller	Conveyor systems where the moving pallet or carrier contacts a rolling stop rather than sliding directly against the rod
Female thread	Installations requiring a threaded attachment at the rod end

The roller version is particularly useful where repeated contact with travelling pallets would otherwise create unnecessary friction or wear against a fixed stopper surface.

Impact Capacity Is a Selection Requirement

Series ST should not be selected from bore and stroke alone. The mass and impact speed of the moving pallet or workpiece determine the energy the stopper pneumatic cylinder must absorb.

Camozzi publishes impact-force and mass-versus-speed sizing data specifically for Series ST. Their current data gives maximum impact-force figures of 1320 N, 3200 N, 5500 N and 6200 N for standard 20, 32, 40 and 50 mm versions respectively, with different limits for non-rotating versions. :contentReference[oaicite:2]{index=2}

Short Stroke, High Cycle Capability

Series ST strokes are intentionally short because the pneumatic cylinder only needs enough travel to engage and release the moving load. Depending on model and bore, standard strokes fall between 5 and 30 mm.

Camozzi rates the 20, 32 and 40 mm versions up to 5 Hz and the 50 mm version up to 3 Hz, making Series ST suitable for repetitive conveyor sequencing where stopping cycles occur frequently. :contentReference[oaicite:3]{index=3}

Magnetic Position Feedback

Series ST is magnetic and provides sensor slots on three sides of the profile for compatible Camozzi proximity switches. This allows the control system to confirm whether the stopper pneumatic cylinder is extended or retracted before releasing or advancing a pallet.

That is especially useful on automated conveyor systems where one station must not release until the downstream stopper position has been confirmed.

What Buyers Need to Check on Series ST

I need to stop pallets on a conveyor. Can I choose Series ST from pallet weight alone?

No. Impact speed matters as well as mass. A lighter pallet travelling quickly may carry more stopping energy than a heavier pallet moving slowly, so Camozzi's mass-versus-impact-speed sizing data should be used when selecting the stopper pneumatic cylinder.

When should I choose the roller-rod version?

The roller version is particularly useful where a moving pallet or workpiece repeatedly contacts the stopper. Rolling contact can reduce sliding friction and surface wear compared with a fixed rod end.

What is the practical difference between ST31 and ST32?

ST31 follows UNITOP dimensional construction, while ST32 follows ISO 21287. ST32 also supports additional non-rotating and roller-rod configurations, so the correct family should be matched to the existing machine design and stopping requirement.

Can Series ST handle side loading?

Yes, within its published limits. Camozzi specifically enlarged the rod and guide bushing to improve resistance to radial loads and shocks, which is a core reason Series ST is suitable for conveyor stopping duties.

Why does the 50 mm version have a lower maximum cycle frequency?

The larger 50 mm stopper pneumatic cylinder handles greater forces and moving components, and Camozzi specifies a maximum operating frequency of 3 Hz compared with 5 Hz on the smaller 20, 32 and 40 mm sizes.

Request Quote

94 pneumatic cylinder products in this range.

Camozzi
ST322R020F010
20mm bore x 10mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322R020F010

£148.55 EX VAT

£178.26 INC VAT

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Camozzi
ST324R020A010
20mm bore x 10mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324R020A010

£148.55 EX VAT

£178.26 INC VAT

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Camozzi
ST322R020A010
20mm bore x 10mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322R020A010

£148.55 EX VAT

£178.26 INC VAT

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Camozzi
ST324A040F030
40mm bore x 30mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A040F030

£126.46 EX VAT

£151.75 INC VAT

View Details
Camozzi
ST322A040F030
40mm bore x 30mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A040F030

£126.46 EX VAT

£151.75 INC VAT

View Details
Camozzi
ST329A040A030
40mm bore x 30mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST329A040A030

£126.46 EX VAT

£151.75 INC VAT

View Details
Camozzi
ST324A040A030
40mm bore x 30mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A040A030

£126.46 EX VAT

£151.75 INC VAT

View Details
Camozzi
ST322A040A030
40mm bore x 30mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A040A030

£126.46 EX VAT

£151.75 INC VAT

View Details
Camozzi
ST322A040F025
40mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A040F025

£125.63 EX VAT

£150.76 INC VAT

View Details
Camozzi
ST324A040A025
40mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A040A025

£125.63 EX VAT

£150.76 INC VAT

View Details
Camozzi
ST322A040A025
40mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A040A025

£125.63 EX VAT

£150.76 INC VAT

View Details
Camozzi
ST322A040A020
40mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A040A020

£124.82 EX VAT

£149.78 INC VAT

View Details
Camozzi
ST324A040F020
40mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A040F020

£124.79 EX VAT

£149.75 INC VAT

View Details
Camozzi
ST322A040F020
40mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A040F020

£124.79 EX VAT

£149.75 INC VAT

View Details
Camozzi
ST324A040A020
40mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A040A020

£124.79 EX VAT

£149.75 INC VAT

View Details
Camozzi
ST329A032F025
32mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST329A032F025

£115.27 EX VAT

£138.32 INC VAT

View Details
Camozzi
ST324A032F025
32mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A032F025

£115.27 EX VAT

£138.32 INC VAT

View Details
Camozzi
ST322A032F025
32mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A032F025

£115.27 EX VAT

£138.32 INC VAT

View Details
Camozzi
ST329A032A025
32mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST329A032A025

£115.27 EX VAT

£138.32 INC VAT

View Details
Camozzi
ST324A032A025
32mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A032A025

£115.27 EX VAT

£138.32 INC VAT

View Details
Camozzi
ST322A032A025
32mm bore x 25mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A032A025

£115.27 EX VAT

£138.32 INC VAT

View Details
Camozzi
ST324A032F020
32mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A032F020

£114.70 EX VAT

£137.64 INC VAT

View Details
Camozzi
ST322A032F020
32mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A032F020

£114.70 EX VAT

£137.64 INC VAT

View Details
Camozzi
ST329A032A020
32mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST329A032A020

£114.70 EX VAT

£137.64 INC VAT

View Details
Camozzi
ST324A032A020
32mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A032A020

£114.70 EX VAT

£137.64 INC VAT

View Details
Camozzi
ST322A032A020
32mm bore x 20mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST322A032A020

£114.70 EX VAT

£137.64 INC VAT

View Details
Camozzi
ST324A032F015
32mm bore x 15mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST324A032F015

£114.11 EX VAT

£136.93 INC VAT

View Details
Camozzi
ST329A032A015
32mm bore x 15mm stroke
Manufacturer Standard | Compact Pneumatic Cylinder
Manufacturer Part Number ST329A032A015

£114.11 EX VAT

£136.93 INC VAT

View Details