In short:Packaging and food machines replace mechanical cams and line shafts with servo axes so formats change from a recipe, not a toolkit. In wet and product zones, choose motors and actuators built for washdown, with the IP rating, materials and hygienic design evidence your customer's hygiene audit will ask for.
Typical requirements
| Washdown ingress | IP69K: 80 °C water at 80–100 bar, 14–16 L/min, 10–15 cm, four angles |
|---|---|
| Hygienic servo motor torque (example) | About 3.1–14 Nm rated in one stainless range (0.45–1.9 kW) |
| Stainless servo actuator (example) | Up to about 3.8 kN continuous, 11 kN peak, 457 mm stroke, IP69K static |
| Housing materials | AISI 304 or 316 (1.4404) stainless, EPDM or FDA-compliant seals, H1 grease |
| Rotary machine slip rings | Up to 250 circuits, 500 A, 1,000 rpm with PROFINET or Ethernet (published range) |
| Servo feedback | 18–22 bit multi-turn absolute, often single-cable (Hiperface DSL, DRIVE-CLiQ) |
What packaging and food machines need from motion
Form-fill-seal, flow-wrapping, cartoning, case packing, filling and capping all repeat the same few moves very quickly: index, feed, cut, seal, transfer. Each machine runs many formats and stops for washdown. Motion choices therefore come down to three questions. How quickly can the machine change format? How well does it survive cleaning? And how much does it lose to stops and rejects, which is what OEE (availability × performance × quality) measures?
Servo axes, electronic cams and changeover
Older machines drove everything from one line shaft through mechanical cams. Modern machines give each function its own servo axis, linked through electronic gearing and cam tables in the motion controller. The benefits show up in all three OEE terms:
- Availability: a format change loads new cam profiles and positions from a recipe. Motorised change parts (guide rails, film widths, tool heights) remove manual adjustment and setting errors.
- Performance: each axis gets the profile its product needs, with jerk-limited moves that let speed rise without spilling or damaging product.
- Quality: registration marks on film or labels are corrected on the fly, and cut and seal positions stay consistent.
Typical axes and what they need:
| Axis | Typical drive | Watch out for |
|---|---|---|
| Film feed and registration | Servo motor with low-backlash gearhead or direct drive | Inertia matching to the reel, registration response |
| Rotary knife or cross-seal jaw | Servo with electronic cam | Peak torque during the cut, RMS heat over the cycle |
| Pick-and-place, transfer | Servo with belt or linear module | Settling time, payload variation |
| Dosing piston or nozzle lift | Servo linear actuator | Washdown, force, repeatability |
| Format change parts | Small integrated servo or stepper | Absolute position at power-up |
For mainstream axes look at servo and stepper motors, servo drives and gearboxes; for coordination, motion controllers. Many lines standardise on the PackML state model (ISA-TR88.00.02) so different machines report states and stoppages the same way, which makes OEE data comparable.
Hygienic and washdown motors and actuators
Food plants divide the machine into zones: dry areas, splash zones, and product-contact areas. The deeper you go, the harder the cleaning and the stricter the design.
Ingress. IP69K comes from DIN 40050-9 (now in ISO 20653). OMRON summarises the test: 80 °C water at 80–100 bar and 14–16 L/min, from 10–15 cm, at 0°, 30°, 60° and 90°, 30 s per angle. It is a jet test, not immersion. IP67 is the immersion test, so specify both if a part may sit in standing water. Check whether the rating applies to the whole motor, including connectors and shaft seal, or only to the housing.
Hygienic design. Ingress protection keeps water out; hygienic design stops soil and bacteria building up on the outside. That means smooth stainless surfaces, no exposed threads or fins, sloped faces that drain, food-grade seals and lubricants, and cable entries without crevices. The EHEDG certification scheme includes cleanability-tested types (EL Class I, which covers items such as gear drive units and sensors), aseptic types with sterilisability and bacteria-tightness tests, and design-evaluated types that assess surface roughness, radii and accessibility. In Europe, EN 1672-2 and EN ISO 14159 set the hygiene requirements for the machine, and Regulation (EC) 1935/2004 governs materials in contact with food.
Examples:
- The Siemens SIMOTICS S-1FS2 is a stainless (1.4404) servo motor with EPDM seals and H1 grease, rated IP66/IP67 overall with an IP69K housing, covering about 3.1–14 Nm rated.
- Allen-Bradley’s Kinetix VPS (304 stainless, Hiperface DSL) and Kinetix MPS (IP66, IP67 and IP69K) serve the same washdown role on Rockwell platforms.
- The Tolomatic IMA-S is a 316 stainless integrated servo actuator, IP69K static, with FDA seals and EHEDG cord grips, for volumetric filling, pumping and slicing.
Stainless gearheads, hygienic couplings and covers matter as much as the motor. A stainless motor bolted to a painted gearbox with an exposed shaft gap is still a cleaning problem.
Worked example: sizing a servo dosing actuator
A piston filler doses 500 ml through an 80 mm bore piston at 30 cycles per minute, with 0.8 s allowed for the fill stroke.
- Piston area: π × 40² = 5,027 mm². Stroke for 500 ml (500,000 mm³) is about 100 mm.
- Speed: 100 mm in 0.8 s is 125 mm/s average; with a trapezoidal profile the peak is about 190 mm/s.
- Force: a viscous product needing 3 bar (0.3 N/mm²) gives 5,027 × 0.3 = 1,508 N, plus seal friction and acceleration. Call it 1.8 kN peak.
- Duty: fill and return run every 2 s, so this is close to continuous. Size on RMS force, not peak.
- Screw: a 10 mm lead needs about 1,140 rpm at peak speed. Check screw life at this force and cycle count; at 30 cycles/min over two 8-hour shifts and 250 days the actuator sees about 7 million strokes a year.
The result sits inside the published IMA-S envelope (3,770 N continuous, 497 mm/s). Confirm the fit with the supplier’s thermal and life calculation, and see how to size a linear actuator and ball screw vs roller screw.
Slip rings on rotary fillers, cappers and wrappers
Rotary fillers, cappers, labellers and rotary-arm stretch wrappers carry powered and monitored parts on a continuously turning turret or arm. A slip ring carries power, sensor signals and fieldbus across the axis, often with a rotary union for air or vacuum.
Moog’s packaging slip ring range is published at up to 250 circuits, 500 A, 800 V and 1,000 rpm with DRIVE-CLiQ, Ethernet and PROFINET options, for winders, flow-pack and stretch-wrapping machines. Points to specify:
- Data: servo heads on the turret need a drive bus or feedback across the ring. Check the protocol and cable category end to end; see Ethernet through slip rings.
- Washdown: brush slip rings must be sealed or housed out of the spray. State the IP rating and cleaning chemicals.
- Speed and life: a wrapper arm or filler turret turning continuously for two shifts builds up millions of revolutions a year. Ask for rated life in revolutions.
- Mounting: through-bore designs leave room for product pipes or a central shaft.
Our pages on slip rings for bottling and filling, wrapping machines and packaging go into detail.
Safety and compliance
Packaging machine safety falls under the EN 415 series, which builds on the machinery directive and regulation. Servo drives with Safe Torque Off and safe speed functions let operators work at guards and change parts without removing all power. Ask for the PL or SIL your risk assessment needs.
Typical pitfalls
- Specifying IP69K and assuming immersion protection, or forgetting the connector and shaft seal.
- Stainless motor, painted gearbox: the cleaning problem moves next door.
- Sizing on peak force for an axis that cycles almost continuously.
- Underestimating revolutions on wrapper and filler slip rings.
- Mixing feedback protocols across a line, so recipes and diagnostics do not carry over.
Send us your axes, cycle rates and hygiene zone, and our specialist engineering and supply partners can propose servo, actuator and slip ring options to suit.
Standards to have in view
- DIN 40050-9 / ISO 20653 (IP69K high-pressure, high-temperature water jet)
- IEC 60529 (IP codes)
- EN 1672-2 (food processing machinery: hygiene and cleanability requirements)
- EN ISO 14159 (safety of machinery: hygiene requirements for machinery design)
- EN 415 series (safety of packaging machines)
- Regulation (EC) No 1935/2004 (materials in contact with food)
- ISO 21469 (lubricants with incidental product contact, H1)
- ISA-TR88.00.02 (PackML machine state model)
Which standards apply depends on the end product and its market. Your engineer will confirm what the component itself needs to meet.
Frequently asked questions
What does IP69K actually test?
IP69K is a close-range, hot, high-pressure water jet test, originally defined in DIN 40050-9. Water at 80 °C is sprayed at 80–100 bar and 14–16 L/min from 10–15 cm, at 0°, 30°, 60° and 90°, for 30 seconds at each angle while the part turns. It is not an immersion test, so an IP69K motor is not automatically IP67; look for both ratings if parts can be submerged.
Can I buy an EHEDG-certified servo motor?
EHEDG certifies specific equipment designs after evaluation, and some motors, actuators and drive units carry certificates. The scheme includes cleanability-tested types such as EL Class I, aseptic types, and design-evaluated types. A certificate covers the certified design and its stated installation, so check the certificate's scope and ask how the item must be mounted. Unlisted parts can still be suitable if the machine builder shows the design is hygienic.
Stainless or painted motors in food machinery?
In splash or product zones that are washed down with caustic and acid detergents, stainless housings with smooth, crevice-free surfaces and food-safe seals are the safer choice. Painted or anodised motors suit dry zones and guarded areas outside the splash zone. The deciding factors are the cleaning regime, chemicals, pressure and temperature, and whether the motor sits above open product.
Why use servo axes instead of mechanical cams on packaging machines?
Servo axes linked by electronic cams change motion profiles from a recipe, so a format change is a menu selection rather than swapping cams and gears. They also allow registration correction, gentle product handling and different profiles per product. The trade-off is cost per axis, more electronics in the washdown area, and the need for good motion programming.
When does a filler or wrapper need a slip ring?
Whenever powered or monitored parts rotate continuously: rotary fillers and cappers with servo or sensor heads on the turret, rotary-arm stretch wrappers, flow-pack sealing jaws and winders. The slip ring passes power, fieldbus or drive feedback and sometimes air through the rotating axis. Specify circuits, currents, data protocol, speed, washdown rating and any rotary union passages together.
What should I send for a packaging axis enquiry?
Send the mechanism and load, stroke or index angle, cycle rate, move and dwell times, accuracy, the zone (dry, splash or product contact), cleaning chemicals, pressure and temperature, required IP rating and materials, mains voltage, the PLC or motion platform and fieldbus, and any slip ring circuits on rotary machines. A sketch of the motion profile helps a lot.
Sources
Figures are summarised from the sources above and from manufacturers' published data on the date shown. Always confirm against the current datasheet for your exact part.