Can one seal material handle every product?
No. Seal behaviour depends on formulation, temperature, exposure time, cleaning chemicals and mechanical duty. The specified material should be checked for the complete operating range.
Materials compatibility
How should product-contact materials be specified for a filling machine?
Filling-machine product-contact materials should be specified by listing every wetted component and checking it against the actual formulation, temperature, cleaning chemicals, contact time and production environment. Stainless steel grade alone is not enough: hoses, seals, gaskets, valve seats, coatings, lubricants and adhesives can be equally important. Compatibility should be confirmed from reliable supplier information and the buyer’s risk assessment.
Wetted pathSeals & hosesCleaningCOSHH evidence
Direct answer
Review the complete wetted path, not only the machine frame.
A defensible specification identifies the tank or hopper, pipework, hoses, cylinder or pump, valves, seals, gaskets, nozzle and any sensor or fitting that contacts product. Each item needs an approved material and evidence appropriate to the product and cleaning process.
- Provide the full formulation or relevant safety data sheet.
- State product and cleaning temperatures.
- Identify solvents, oils, acids, alkalis, particulates and abrasives.
- Define contact time, cleaning method and replacement strategy.
Component register
Which product-contact parts need material approval?
| Component | Compatibility questions | Evidence to retain |
|---|---|---|
| Tank or hopper | Product, temperature, agitation, drainability and cleaning chemical | Material grade, finish and supplier declaration |
| Hoses and pipework | Solvent, pressure, bend radius, temperature, permeability and cleaning | Hose specification and replacement interval |
| Cylinder or pump | Abrasion, shear, lubrication, corrosion and cleanability | Wetted-parts list and maintenance guidance |
| Valves and seats | Particle passage, swelling, sticking and chemical attack | Valve material, seat material and trial evidence |
| Seals and gaskets | Swelling, hardening, extraction, temperature and cleaning exposure | Material data, approved spare part and inspection interval |
| Nozzle and fittings | Cut-off, particles, finish, corrosion and product retention | Drawing, material and cleaning access |
Buyer question
Is specifying stainless steel enough?
No. Different stainless grades, surface conditions and fabrication details can behave differently, and the product may also contact elastomers, plastics, tubing, adhesives or lubricants. The complete wetted-parts schedule should be checked, not a single headline material.
Use the product supplier’s evidence. Safety data sheets describe hazards and handling information but do not replace a COSHH risk assessment or a detailed compatibility review.
Chemical and cleaning evidence
How should safety data and cleaning information be used?
Provide the latest safety data sheet for hazardous chemical products and details of every cleaner or sanitiser that will contact the equipment. Use that information to support the buyer’s COSHH assessment, material review, ventilation, containment, isolation and operating procedure. The machine supplier still needs formulation-specific compatibility confirmation where the safety data sheet does not provide it.
- HSE guidance explains how chemical safety data sheets support risk assessment.
- HSE PUWER guidance covers suitability, maintenance, instruction and protective measures.
- Include cleaning concentration, temperature, contact time and rinse method.
- Record approved alternatives so emergency spare parts do not introduce an unreviewed material.
Common questions
Questions about filling-machine product-contact materials
Do cleaning chemicals count as product-contact exposure?
Yes. A component can tolerate the filled product but fail under a concentrated cleaner, hot wash, steam or repeated sanitising cycle.
What if the formulation is confidential?
Provide enough controlled information for compatibility to be assessed, such as a safety data sheet, chemical family, concentration range, temperature and a supplier-led material review under an appropriate confidentiality arrangement.
How should abrasive particles be considered?
Review valves, cylinders, pumps, seals, bends and nozzle restrictions for wear. The maintenance plan should identify inspection points and acceptable replacement parts.
Who approves the final material list?
The buyer should approve it using product-supplier information, component-manufacturer evidence, the machine supplier’s scope and the application-specific risk assessment.
What change control is needed after purchase?
Record the approved material and part number for each wetted component, then review any substitute seal, hose, lubricant, cleaner or formulation before use.
Related guidance
Connect compatibility to cleaning, maintenance and the URS.
Send the product and cleaning evidence before materials are fixed.
Lancing can then review the wetted path, change parts and supplier evidence as part of the machine specification.