KHS Innofill Filler Maintenance: Sealing, CIP Drift and Head Tests

Start with the head that is actually failing

The reject counter rises, but the display says the filler is within setpoint. One KHS Innofill head may be low while its neighbors are stable. Or all heads shift after CIP and recover partly when the product warms. These are different faults and they need different evidence. Use five bottles per head. Weigh them, calculate the range, and keep the head position with the record. A small table made every week is more useful than a single “pass” note because it shows whether a seal is deteriorating or the whole machine is moving together.

Why a timer adjustment hides the fault

Fill volume depends on sealing, pressure, flow, product temperature and container presentation. A timer adjustment changes the symptom but not the reason. If a valve leaks through the product seal, more time can increase overfill on some bottles and still leave a low result on others. If the ring tank level is unstable, adjusting individual heads creates a new set of offsets. On an Innofill, keep the test physical. Take a sample from one head, compare it with a reference head, then test the machine-wide pattern. The sequence is important: one head suggests a valve or seal; all heads suggest level, calibration or product condition; foam without a large mass error suggests gas behavior.

1. Test each filling head with five bottles

Run at the normal speed and product condition. Collect five consecutive bottles from the suspect head, label the head position, and weigh each bottle with the same method. Repeat with five bottles from a reference head. Calculate the average and the maximum minus minimum for each group. A low average with a narrow range can indicate a repeatable setting or pressure issue. A wide range points more strongly to a sealing or mechanical problem. Repeat the test after a short controlled pause. If the result follows the same head, inspect its valve assembly. If the result follows the whole carousel, move upstream to level and calibration. Replace a confirmed failed seal with a compatible replacement that matches the product-contact material and dimensions. Photograph the old part before cleaning it. The wear pattern can show whether it was compressed, cut, chemically attacked or running on a damaged surface.

2. Separate the product valve seal from the CIP valve seal

The Innofill valve can have more than one sealing surface involved in product and CIP paths. Confusing them leads to a part that fits but does not solve the leak. A product valve seal problem normally shows product wetness or a fill loss at the product side. A CIP seal problem can allow cleaning liquid to enter the product path or create a contamination risk after the cycle. Clean and identify the area before the next test. Observe the machine during the approved CIP or rinse procedure. If liquid appears at the product side during a CIP step, note the step, temperature and chemical condition. If product appears outside the product path during production, inspect the product-side seal and stem first. Do not select a replacement by outside diameter alone. Confirm the position, material, hardness and service path. A form-fit-function alternative must be suitable for the chemical and temperature exposure. If the position is unclear, send the part photos and the valve location instead of ordering by a similar-looking picture.

3. CIP can make a real problem look intermittent

Alkaline and acid cycles stress elastomers. Deposits can also dry on a seat and break loose when the machine returns to production. A common pattern is a deviation immediately after CIP, followed by partial recovery after the filler has run hot for a while. That pattern is evidence, not a reason to ignore the issue. Record four times: the end of CIP, the first fill check, the point where the line warms up, and the first stable result. Compare the weight spread and the wetness around the valve at each point. If the fault returns after each cycle, inspect seal hardness, surface cuts and seat residue. If all heads move together, include flow measurement and level control in the test. Replace a hardened or damaged seal and clean the mating surface according to the approved procedure. Do not sand a product-contact seat without knowing the allowable finish. If the seat has changed shape, a new seal may only provide a short recovery.

4. Ring tank level affects every head

An Innofill filler uses a common product supply condition for the heads. When the ring tank level or pressure moves, the result can shift across the carousel. The symptom is a similar underfill or overfill on many heads, with no single position standing out. Watch the level while the filler starts, changes speed and returns from a disturbance. A display that stays at setpoint can still be wrong if the sensor is offset. Compare the displayed level with the independent check available in your procedure. Observe whether a control valve hunts or recovers slowly. Correct the control cause before replacing a head seal. If the sensor, valve or pneumatic actuator is confirmed defective, use a compatible replacement with the correct range and connection. The relevant parts may sit under Sensors, Pneumatics or Automation.

5. Carbonated product may show foam before a volume error

With carbonated product, a worn valve can disturb pressure release and cause excessive foaming. The bottle may look full or short while the mass is still close to target. This is why a visual fill line alone is not enough. Compare weight, foam height and the pressure conditions at the same time. If the symptom is foam at one head, inspect sealing and valve movement. If foam appears across the machine, check product temperature, CO2 condition, pressure balance and the ring tank. A worn valve can create a local gas release, while a product condition affects every head. Record the time from valve opening to stable flow if the machine makes that observation available. Replace the confirmed worn sealing components and verify the result with weights after the line reaches normal temperature. Avoid inventing a fixed replacement period for KHS filling valve seals. The correct interval depends on product, CIP, speed and the measured trend.

6. Build a weekly record that can show drift

Each week, record the date, machine speed, product, product temperature, CIP time, ring tank level, head position, five bottle weights and the range. Add a short note for leaks, foam, valve noise and any temporary adjustment. The purpose is to see movement, not to create paperwork. Plot the range for each frequently used head. A head that widens over several checks deserves inspection before it produces a stop. A step change on every head after a CIP cycle points to a common condition. A record with no head position cannot support that distinction, so label every sample. For planned work, pair the sealing set with any spring, guide or stem component that the inspection shows to be worn. Keep the old part with the record for supplier review. See Filling machine parts and the Full parts catalogue when the part identity is uncertain.

What to replace, and what to replace at the same time

Field checklist

Record the exact head position and product before changing a setting. Collect five consecutive bottles from the suspect head and weigh them using one method. Repeat the sample on a reference head and calculate both averages and ranges. Classify the fault as head-specific, carousel-wide or foam-dominant. Clean the valve area under the approved procedure and identify where wetness returns. Observe the approved CIP or rinse step and record whether liquid crosses the product-side seal. Check seal hardness, cuts, flattening and the condition of the stem and seat. Watch ring tank level and pressure during startup and a speed change. Record product temperature, CO2 condition and the time since CIP. Replace only the confirmed failed part or matched sealing set, then repeat the weight test. Add the result, old part photo and new part identity to the weekly head record.

When to stop repairing and overhaul

Stop repeating seal changes when the same head fails after a short run, the stem has a groove, the seat is pitted, or the spring has lost force. A local repair is reasonable when the valve geometry remains sound and the fault is isolated. Plan a group overhaul when several heads show the same wear pattern or when opening the filler twice would cost more than combining seals, guides and inspections in one controlled stop. An overhaul scope should distinguish product seals from CIP seals. Include the parts that establish alignment and closing force, not only the elastomer. If the machine has a history of post-CIP drift, include calibration evidence and ring tank checks in the same work order. A compatible replacement is useful only when position, material and dimensions are confirmed.

FAQ

What is the best first test on a KHS Innofill filler?

Take five bottles from the suspect head and five from a reference head, then calculate the average and range. Keep speed, product temperature and machine settings unchanged. The pattern tells you whether to inspect one valve or a common supply, calibration or product condition.

How can I tell whether a product seal or CIP seal is leaking?

Identify when the liquid appears. Product outside the product path during production points to the product-side sealing area. Cleaning liquid entering the product path during the CIP step points to the CIP-side sealing area. Record the cycle step and chemical condition before selecting a part.

Does KHS publish a fixed interval for filling valve seals?

Do not apply a universal interval unless it is stated for your exact application. KHS may publish example maintenance concepts for wear parts, but a filling valve seal interval depends on product, temperature, speed and CIP exposure. Build the local interval from head-by-head trend data.

Why does the filler foam after a valve has started wearing?

A worn valve can disturb the pressure release path, especially on carbonated product. Foam may appear before the bottle mass moves far from target. Check weight, foam and pressure together. If all heads foam, investigate product and common pressure conditions before replacing one valve.

What information should I send for a replacement seal?

Send the machine series, head position, part marking if visible, two photos from different angles, the old seal dimensions if available, product type and CIP conditions. Include the five-bottle test result. That evidence avoids choosing a seal by appearance alone. Need a specific part? Send the machine model, the position number and two photos of the part — we quote within one business day. → Send your parts list

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