{"id":"wpc-tech100-article-012-en","slug":"gravimetric-feeder-checks-for-wpc-production","locale":"en","url":"https://woodplasticcomposite.net/guides/gravimetric-feeder-checks-for-wpc-production/","title":"Gravimetric feeder checks for WPC production","answer":"Feeder accuracy affects whether the intended WPC recipe reaches the machine consistently. Calibration should address the material and operating conditions, not only an empty equipment display.","author":"NFC & WPC Knowledge Reference","faqIds":["wpc-tech100-faq-012-en"],"tagIds":[],"noindex":false,"related":["wpc-tech100-article-013-en"],"version":1,"modified":"2026-10-15","reviewer":"","sections":[{"id":"technical-context","text":"A loss-in-weight feeder estimates delivery from changing measured mass. Refill cycles, vibration and material flow can complicate interpretation. A stable total output does not prove that each individual ingredient is being delivered at the intended rate.","heading":"Technical context","references":[],"url":"https://woodplasticcomposite.net/guides/gravimetric-feeder-checks-for-wpc-production/#technical-context"},{"id":"verification-plan","text":"Use the equipment maker's approved verification procedure and suitable independent mass checks. Record feeder setpoint, actual delivery, refill behaviour and the relevant material lot. Compare short disturbances with the time window used for collecting test specimens.","heading":"What to measure and document","references":[],"url":"https://woodplasticcomposite.net/guides/gravimetric-feeder-checks-for-wpc-production/#verification-plan"},{"id":"practical-decision","text":"Keep feeder maintenance and calibration evidence with batch records. If the formula is correct on paper but properties drift, examine delivery consistency before reformulating. No adjustment should bypass guards or interlocks on operating production equipment.","heading":"Implications for development and specification","references":[],"url":"https://woodplasticcomposite.net/guides/gravimetric-feeder-checks-for-wpc-production/#practical-decision"},{"id":"reading-scope","text":"Official guidance on controlling measurement processes and supporting uncertainty statements. Use the linked work as related reading. The practical checks above are editorial recommendations, not reported test results or a substitute for product qualification.","heading":"Related reading and evidence limits","references":[1],"url":"https://woodplasticcomposite.net/guides/gravimetric-feeder-checks-for-wpc-production/#reading-scope"}],"seoTitle":"Gravimetric feeder checks for WPC production | WPC Reference","topicIds":[],"published":"2026-10-15","tableText":"Review step | Evidence to retain\nMaterial and geometry | Exact specimen or product identity\nVerification | Method, conditions and individual observations\nDecision | Approved scope and documented limitations","takeaways":"A loss-in-weight feeder estimates delivery from changing measured mass.\nUse the equipment maker's approved verification procedure and suitable independent mass checks.\nKeep feeder maintenance and calibration evidence with batch records.","aiAssisted":true,"categoryId":"wpc-tech100-category-1","reviewedAt":"","change_note":"New focused technical draft; not a product certification or production recipe.","description":"Feeder accuracy affects whether the intended WPC recipe reaches the machine consistently.","heroImageId":"","referenceIds":["wpc-tech100-ref-measurement"],"review_status":"AI-assisted English editorial draft. Human technical review has not been recorded.","table_caption":"Evidence checklist for gravimetric feeder checks for wpc production","seoDescription":"Feeder accuracy affects whether the intended WPC recipe reaches the machine consistently.","translationGroup":"wpc-tech100-012-2026","references":[{"url":"https://www.itl.nist.gov/div898/handbook/mpc/section2/mpc2.htm","type":"web","title":"NIST: statistical control of measurement processes","noindex":false,"accessed":"2026-10-14","seoTitle":"NIST: statistical control of measurement processes","publisher":"NIST","description":"Related reading; scope and limitations are identified in each article.","seoDescription":"Related reading; scope and limitations are identified in each article."}],"faqs":[{"question":"What evidence is needed for gravimetric feeder checks for WPC production?","answer":"Use the equipment maker's approved verification procedure and suitable independent mass checks. Record feeder setpoint, actual delivery, refill behaviour and the relevant material lot. Compare short disturbances with the time window used for collecting test specimens."}]}