Yadda ake daidaita lokacin fara kumfa (cream time) a cikin Ƙarƙashin Ƙarfafa PU Sandwich Panel Production yayin Babban Humidity

Ga masana'antun sandwich panel masu gudana da ci gaba da layin lamination, ƴan matsalolin samarwa sun fi takaici fiye da drift na lokacin fara kumfa (cream time) na yanayi. Allolin da ke gudana daidai a lokacin rani ba zato ba tsammani suna haifar da lahani na sama, lokacin zama gel (gel time) yana miƙewa, da ƙidayar ƙidayar hawa - duk saboda yanayin yanayi ya ƙetare kofa marar ganuwa kusa da 85% RH.

Wannan ba rashin daidaituwar masana'anta ba ne. Matsala ce ta ilmin sinadarai tare da dabaru guda uku da aka fahimta sosai.

Dalilin da ya sa Danshi ke haifar da matsalar lokacin fara kumfa (cream time)

lokacin fara kumfa (cream time) na tsarin polyurethane an ƙayyade shi ta ƙimar farkon NCO–OH, matsakanci ta manyan masu haɓaka amine. A cikin tsayayyen tsari, wannan amsa yana gudana akan ƙimar da za a iya faɗi ta hanyar:

• Nau'in sinadarin hanzarta aiki (catalyst) da yawan amfani da shi (yawanci 0.3-1.5 phr na tertiary amine)
• Zafin tsarin (ana kiyaye shi a matakin 20-25°C yayin zuba kayan)
• Matsayin (index) na polyol da isocyanate (yawanci 1.05-1.15 don tsarin kayan da ke da tauri/rigid)

Lokacin da zafi na yanayi ya tashi sama da 85% RH, hanyoyi guda biyu suna lalata wannan ma'auni:

1. Sharwar ruwa a cikin bangaren polyol. Polyether polyols suna da ɗan ƙaramin hygroscopic. A babban zafi, danshi na yanayi yana yaɗuwa cikin drum polyol yayin buɗewa, rarrabawa, da zagayawa. Ruwan da aka narkar da shi sannan ya yi gasa tare da ƙungiyoyin polyol hydroxyl don isocyanate, samar da CO₂ da haɓaka matakin farko-exotherm.
2. Damshin saman saman da ke kan ma'ajin. Ko da tare da ajiyar ganga mai sarrafawa, fuskar karfen da ke shiga layi mai tsayi tana ɗaukar danshin saman da ke amsawa yayin haɗuwa da kumfa mai tasowa, a cikin gida yana hanzarta samuwar fata.

Duk hanyoyin biyu suna gajarta lokacin fara kumfa (cream time), amma suna yin haka ba daidai ba - yawancin halayen da ake yi suna raguwa yayin da yanayin yanayin ke tafiya gaba. Sakamakon: lahani na bayyane (blisters, cratering, saƙa Lines) ko da lokacin da babban tsarin kumfa ya dubi abin karɓa.

Dabaru Uku na Rage Tasirin Matsala

Dabara 1: Daidaita sinadarin Catalyst

Hanyar da ta fi dacewa kai tsaye ita ce a matsar da fakitin mai kara kuzari zuwa aikin sinadarai na jinkiri.

• Rage yawan sinadaran 'gel catalysts' (PMDETA, DMCHA) da kashi 10-15%
• Ƙara yawan sinadaran 'blow catalysts' (BL-11) bisa ƙa'idar da ta dace
• Ƙara ɗan ƙaramin adadin sinadarin amine mai jinkirin aiki (misali, DABCO BL-17 ko makamancinsa)

Ciniki-kashe: lokacin cire samfur daga mould (demould time) mai ɗan tsayi (yawanci +5 zuwa +10 daƙiƙa), wanda zai iya buƙatar ƙaramin daidaita saurin layi.

Sakamakon da ake tsammani: lokacin fara kumfa (cream time) ya daidaita cikin daƙiƙa ±1 a yanayin zafi mai ɗauke da danshi na 60-92% RH.

Dabara 2: Sake tsara sinadarin Surfactant

Silicone surfactants suna sarrafa tsarin tantanin halitta yayin hawan kumfa. Ƙarƙashin yanayin zafi mai ƙarfi, daidaitattun kayan aikin surfactants na iya zama ƙasa da tasiri wajen daidaita bangon tantanin halitta yayin haɓakar matakin farko.

• Canzawa daga daidaitaccen sinadarin 'silicone surfactant' na ƙarancin nauyin molekul (MW) zuwa nau'in mafi girman nauyin molekul (MW) da aka kera musamman don jure wa kasancewar danshi
• Gyara na yau da kullun: 1.5-2.5 phr na nau'in mai jure wa danshi aji

Abin da za a yi la'akari da shi: Karin kudin kayan aiki kadan dangane da sinadarin 'surfactant' (yawanci karin +5-10% kan wannan bangaren).

Sakamakon da ake tsammani: Ingancin saman abu yana kasancewa iri ɗaya ba tare da la'akari da yanayin danshi ba. Yana rage yawan kurakuran saman abu daga 4-6% zuwa ƙasa da 1%.

Dabara 3: Busar da sinadarin Polyol tun da wuri

Don ayyukan da ba za a iya yin gyara ba (misali, ƙwararrun ƙayyadaddun abokin ciniki waɗanda ke kulle tsarin), madadin shine sarrafa danshi na sama.

• Sanya na'urar tace danshi ta 'molecular sieve' a kan bututun ajiye polyol
• Kiyaye yawan danshi a cikin polyol ƙasa da 0.05% (daidai da ƙa'idar Karl Fischer)
• Yi amfani da rufin iskar nitrogen busasshiya a kan polyol ganguna yayin zuba shi

Abin da za a sadaukar: Zuba jari a kayan aikin busarwa (yawanci $15,000-30,000 USD dangane da ƙarfin layin samarwa). Ba a buƙatar canza tsarin haɗin sinadaran ba.

Sakamakon da ake tsammani: Yana cire dogaro da yanayin danshi na waje gaba ɗaya daga tsarin haɗin sinadaran, amma yana buƙatar ci gaba da kula da kayan aiki.

Zaɓin Dabarar da ta Dace

A aikace, yawancin abokan ciniki muna aiki tare da ɗaukar Dabaru 1 da 2 a hade - matsakaicin matsakaicin mai kara kuzari wanda aka haɗa tare da mai jure ɗanshi. Wannan haɗin yawanci yana ba da ingantaccen samarwa a cikin kewayon zafi ba tare da buƙatar saka hannun jari ba.

Tabbatarwa a Wurin Aiki: Abubuwan da za a Gwada

Kafin ƙaddamar da tsarin da aka gyara akan sikelin samarwa, tabbatar da gwajin layin wakilai:

1. lokacin fara kumfa (cream time) da lokacin zama gel (gel time) an auna shi a yanayi uku na danshi (60% RH, 75% RH, 90% RH an yi shi da kwaikwaya)
2. Rashin lahani na saman sama a fadin 100 rukunoni jere a kowane yanayin zafi
3. Ƙarfin ƙarfi na gama gari (kowace EN 14509 ko daidai daidaitaccen yanki)
4. lokacin cire samfur daga mould (demould time) an auna shi da lokacin zagayowar samarwa na yanzu
5. B1 ko B2 aikin hana gobara yana riƙe da SNI, EN, ko ƙa'idodin yanki.

Cikakken ingantaccen yana ɗaukar makonnin 2-4 daga karɓar samfurin zuwa ƙirar ƙira.

Yin aiki tare da MENGWEI kan matsalolin lokacin fara kumfa (cream time)

Idan kuna ci gaba da ci gaba da layin lamination wanda ɗigon lokacin fara kumfa (cream time) ke motsawa, ƙungiyar fasahar mu na iya samar da:

• Samfuran sabon tsarin haɗin sinadarai (reformulation) da aka daidaita su da ɓangaren isocyanate da kuke amfani da shi yanzu
• Tallafin gwajin layin samarwa da matakan tabbatar da inganci a wurin aiki
• B1/B2 takaddun yarda da gobara don ma'aunin yankin ku
• Ci gaba da bayar da rahoton inganci na kowane rukuni (batch) na samarwa

Nemo ta hanyar Nemi tayin farashi tare da maƙasudin lokacin fara kumfa (cream time)/lokacin zama gel (gel time) na yanzu, kewayon yanayin yanayi, da saurin layi. dakin gwaje-gwajenmu na R&D a Jinshan yawanci yana amsawa cikin kwanaki biyar na kasuwanci tare da shawarar ƙira.