Daily inspection of sealing rings in beverage production line: External visual inspection can only make preliminary judgments, and key workstations must be regularly disassembled and inspected; Many microcracks and internal deformations cannot be seen from the outside; Inspection should take into account both equipment sealing performance and microbiological hygiene risks.
There are three types of inspections: per shift inspection (without disassembly), weekly/batch production change inspection (partial disassembly inspection), and monthly regular disassembly inspection (in-depth inspection). All inspections are conducted after shutdown and power outage.
Each shift inspection of the sealing ring
Suitable for: filling machine valves, quick release clamp joints, pump end caps, heat exchanger flanges, etc., appearance inspection
- Leakage inspection
-Observe the sealing position for material leakage, water stains, sugar stains, and adhesive residue;
-Is there any accumulation of syrup or juice crystals around the clamps and flanges; Leakage indicates compression failure, assembly deviation, or damage to the sealing ring. - Macroscopic appearance status
-Whether there is obvious swelling, extrusion, or local flanging (the sealing ring is squeezed out of the flange gap);
-Whether there are obvious cracks, gaps, or falling pieces. - Surrounding hygiene conditions
Whether there is any accumulation of material residue, mold spots, or black dirt in the sealing gaps and clamp grooves; There is a pile up indicating the presence of hidden materials in the corners. Even if there is no leakage, it should be marked and planned for dismantling and inspection. - Status of clamps/fasteners
Are the clamps and bolts loose; Loose positions with high vibration can change the compression of the sealing ring, accelerate damage, and form gaps.
Attention: Each shift does not disassemble, only obvious faults can be found, and micro cracks and internal pressure injuries cannot be detected.
Weekly inspection of sealing rings
2、 Weekly inspection of sealing rings
Key workstations: UHT, sterilization machine, sterile filling valve, CIP interface, heat exchanger, feed pump, storage tank hole.
Remove the sealing ring and observe both the sealing ring body and the sealing groove on both sides.
Inspection of the sealing ring body
- Surface cracks and fissures
Under strong light, there are small turtle cracks and radial microcracks on the surface; Even if there is no cracking or penetration, it is still aging. It is recommended to replace it directly in the high-temperature section. - Deformation inspection
-Is there a permanent indentation that cannot rebound when released;
-Whether there is distortion, local expansion and swelling (enlargement, softening and sticking);
-Has it become hard and lost elasticity, with slow rebound when pressed with fingers. - Surface damage
Scratches, incisions, local wear and peeling; Many are caused by installation pry injuries. - Color change situation
Obvious yellowing, blackening, and localized discoloration due to material erosion.
Sealing groove (easily overlooked) - Clean up the internal scaling, sugar deposits, and material deposits in the trench;
- Check for corrosion pits, pitting, and wear in the grooves; The groove is damaged, and replacing the sealing ring will still hide material and leak;
- The groove is free of burrs and metal debris.
Assembly review - Whether the sealing ring model and material match the workstation, and whether there is any wrong installation;
- The assembly is free from distortion and particles are not trapped on the sealing contact surface.
Monthly deep disassembly inspection
- All high-temperature workstations (UHT, SIP sterilization) valve groups and joint sealing rings shall be dismantled and inspected;
- Measurement observation: whether there is significant shrinkage or flattening of the O-ring section;
- Differentiation: normal elasticity/decreased elasticity;
- Synchronize the status of spare parts, identify vulnerable locations, and analyze whether it is a material, installation, or CIP process issue;
- Microbial sampling (optional): Suspect contamination risk points, conduct surface coating testing, and determine the microbial load in the gaps.
List of Key Inspection Points for Different Equipment
- UHT/ultra-high temperature sterilization machine: plate heat exchanger sealing gasket, sterilization pipeline clamp, steam interface, discharge valve sealing ring; High risk, dismantle and inspect first.
- Filling machine: filling valve O-ring, valve core seal, material cylinder hole, reflux pipeline seal.
- Storage tank: hole sealing ring, breathing valve seal, quick release seal for discharge port.
- Material pump: pump shaft mechanical seal, pump cover flange sealing ring.
- CIP system: Clean the circuit joints and seal the reversing valve.
The content that needs to be recorded for spot checks
- Equipment location, sealing ring model and material;
- Phenomenon: leakage, crystallization, cracking, swelling, permanent indentation, groove corrosion;
- Judgment result: Normal – Continue observation – Replace immediately;
- Change time and personnel.
Inspection and judgment criteria
Normal: Smooth surface, good elasticity, no cracks or indentations, clean grooves, no leakage or material accumulation.
Observation: Slight indentation, no cracks or leaks; Shorten the next inspection cycle, and it is not recommended to continue using high-temperature workstations.
Replace immediately:
- Any visible cracks, microcracks, or gaps;
- Swelling, sticking, hardening, permanent indentation without rebound;
- Scratch the incision;
- The corrosion of the groove cannot be repaired, and the groove should be treated at the same time.
Common Misconceptions in Inspection
- Only look for leaks and do not leak materials: no leaks ≠ intact sealing rings, no water leakage from micro cracks, but may hide materials and breed microorganisms;
- Only focus on the sealing ring and ignore the sealing groove; The groove is damaged, and no matter how many sealing rings are replaced, it cannot be solved;
- Relying solely on external inspections for each shift, without dismantling inspections for a long time; Microcracks in the high-temperature section are not visible from the outside.