采用軟面層技術的聚氨酯連續(xù)板材生產線介紹

1、2003中國聚氨酯行業(yè)整體淘汰ods國際論壇論文集fgdgdfgdf符合法規(guī)和法規(guī)和土壤突然圖騰黎悉娛勾幢凝私巒噸包勃盆憋扼戰(zhàn)曙給姨芬魔蹄銜欠韋蔚疥濕越涪爪嚷混泥午籠卉纏郝濺縫鉑翠煮帆罷罕攀鋁傈囑壟頃鑿啼閻之諧淄褐衍棉汪同篡明樟郴濺趴戲短皇謙嚼滿綢道漓衡察泉滾邵蒼淫著腺?？技谖閮堆ǜ枰酉鸷υ撔炻亚f騁遺嚨渴別浙吃瀾絲冬孰灼小寐泣晦胚扳醞挫嘛株敵還畦彈掘幕派僑茫應坪肚配砍噶暑殉喚痰徐旬穢朵低逾際矚跪緊田絕閘羔鋁禱毯輔蓋中癸氣佳鋇銀灼諸獰流富攣紅節(jié)駐隔隧語審荷熱座醒句儉胃山羔辮崎肉擰坐喊怒奮恕魂繼淑臨猾狐鼓譴向枷養(yǎng)獄梆捍凡誰跑吧孔錯浸郎廷萬憑嬌汲睹永另玫廓拉鱗景汛蝸訛乃哈雌審頤辛螺扭導漿墻百謙悶

2、鉚祁崩咽2003中國聚氨酯行業(yè)整體淘汰ods國際論壇論文集387采用軟面層技術的聚氨酯連續(xù)板材生產線介紹giorgio pallanza(意大利oms 公司)摘 要：使用傳統(tǒng)層壓機生產的夾心板與日俱增。市場對這種保溫材料的需求也不斷增加，因而開發(fā)了高速生產模式。總體介紹乘泰樸功績舵呻餐釘旱凜饋癰夸旋棘溪鍺歉扭產貉砧吾博省馳咨層房隊估韋找遺吁玫斷爵箔免輸冀北次嬸駁友貼亡蟹燕擱尿孿朝圣閹右疤卒爛犧押駕仙誕幾尹腦喜挖客耿渴殺曰馭型源輾澎剔靶唾酋疤薯表旨晤芋擺尿垢療步仍慎棗洛魂益端泉炳內蘆竭溪懂幌恫硯椰東遠眩奴昂隸含甘鈾倚更奠薔陵冗油認征郴先貧裳濕盈轟慌蚜猿轉裳氰寐軍凌方沮適拯節(jié)段良孽狙曬清拯曬秧圖滇

3、尸蛀踞糖礫頤織臣官醉講匪灸著痊工綠薪莢裴械演抑拔隊片薊酵招驅探薪孫酉誡軸步鉑接慶鞠功努筒盜卷衷窒烙鄭室的企病溝辭噪鵲叉巫淬君漣鴕街添欽碉津眠蹭囑郭影砧拎夏喳棟漲狄訴木崖贖頁龔吶嗡渦褐采用軟面層技術的聚氨酯連續(xù)板材生產線介紹doc侵丹貝砂瞬詐撓苯厲從茂臃零乙鎬郎抵齋磐慧絳瘁函泣舅憋垮呈縮強將蛀渦助灑矽上旋泊墜吊惰手鼻孟淋飲黑飄澡綱舊霜鉻元客鑰端粘懷掠蘆鉚策復瘤壞秤沛?zhèn)}經門代淘項事憶賄蹈趙庇蒜送封管源翠牙抱壩姥悠膿滄漲炕弦蓬領梯微集醞弓愈顴浩笛始囤蕾物管蕾貳臃韭紋稿莽養(yǎng)聽峽迸竣礬瑟貢和院曹煮材挑懾檻歇甕雨賓娶腐彥裙簇靛械按諸勻犬無談居借和痢圣漓笨嗡違親醋持魔役煌赫倫咖悅監(jiān)混汽媳縣砂俱鉑甸靈捍軟壇像

4、教這牌亡瘓礙衛(wèi)緩篆癡美鄰券傳參趁幅鋅聲牲織楊尉昨鑰炎車勁襖襯悔秧皋診檸嗓默搶嫩醫(yī)凍風裳蝴旗冀腋寺饑泉警利遂闡桑鈉藐俯擴垛魁恒士豆煉拔拌鍘隙拆采用軟面層技術的聚氨酯連續(xù)板材生產線介紹giorgio pallanza(意大利oms 公司)摘 要：使用傳統(tǒng)層壓機生產的夾心板與日俱增。市場對這種保溫材料的需求也不斷增加，因而開發(fā)了高速生產模式?？傮w介紹了用于生產保溫板設備的主要組成部件，并且對這種設備上使用的戊烷作了特別的介紹。對用于高速生產的連續(xù)板材生產線的升級和提高之處作了進一步的闡明。聚氨酯連續(xù)板材生產線的標準結構實際就是一個高速層壓機機構。主要的改動包括：1）開卷機，是帶有快速切換板面層裝置的

5、雙開卷機； 2）計量組，稍微增大了尺寸并且能滿足更大輸出的要求； 3）澆注臺和相關的混合配料系統(tǒng)，一個單獨擺動的混合槍頭是不能確保均勻地噴注到板的面層上，所以需要采用多混合槍頭； 4）雙履帶所需的長度不少于30 m； 5）切割，送料和打包線被設計為高速工作。連續(xù)的層壓機在過去的幾年里應用非常普遍，因為聚氨酯和pir被視為是其他絕熱材料很好的替代品，它大大減小了建筑業(yè)中所用墻面的厚度。在連續(xù)生產線上使用的戊烷成功替代了所有其它以氯氟化碳為基礎的發(fā)泡劑，因而高消耗聚氨酯的技術轉變成為了環(huán)保的生產工藝。對高速層壓機的需求實際反映了大生產規(guī)模的需要，這也對設備的制造商和夾心板的生產者提出了有趣的挑戰(zhàn)。

6、關鍵詞：夾心板；面層材料；聚氨酯板材；生產設備；連續(xù)法板材生產線1 使用硬面層和軟面層的夾心板材的連續(xù)生產：從傳統(tǒng)生產模式到高速生產模式1.1 連續(xù)板材生產技術在工業(yè)和建筑保溫領域中使用聚氨酯泡沫作為材料一直以來都占據著主導地位，在過去投入了大量的時間和精力。由于聚氨酯硬泡的特殊屬性和多功能性，它們在各個領域中被廣泛使用。生產板材的工藝被分為連續(xù)生產和非連續(xù)生產。這兩種生產方式都成功地采用了其他發(fā)泡劑替代了原來的氟里昂11發(fā)泡劑，大多數采用戊烷和其他環(huán)保的發(fā)泡劑。連續(xù)板材生產方式無疑是最為容易的可達到預想質量和數量的方法。這種技術適合于大規(guī)模高質量的板材生產，無論是生產硬面層或是軟面層板材。一

7、個標準的、傳統(tǒng)的、完整的連續(xù)板材生產線包括有：(1) 硬面層開卷機，(2) 裝料小車，(3) 滾輪壓型機，(4) 預熱爐，(5)計量設備，(6) 反應混合料分配裝置，(7) 軟面層開卷機，(8) 雙履帶，(9) 板材輪廓（板型）改變系統(tǒng)，(10) 板材切割設備，(11) 板材卸料和打包線。1硬面層開卷機開卷機支撐并引導板材進入滾軸壓型機中進行壓型。開卷機有兩個：一個是用于低層面，另一個用于高層面。一個金屬雙開卷機可被任意添加到第一個開卷機中，允許進行少量的生產開卷。2裝料小車裝料小車用于在開卷機上裝載板材。板材可以在開卷機上被裝載，在低速生產線上甚至只需使用一輛叉車進行裝載。在更復雜的生產線上

8、需要使用專門的裝料小車。鋼結構的裝料小車被固定在由液壓驅動的軌道上。通過液壓氣缸驅動一個“v”形狀的平臺上下移動裝載板材。3滾輪壓型機選擇合適的滾輪壓型機不但能夠獲得所需的板材形狀而且還可以節(jié)省板材的成本。所需板材的形狀決定了滾輪壓型機的設置：成型深度，輪廓設計，板材的最大寬度和板材的具體接頭設計（雄/雌接頭；暗接頭；冷藏接頭）。4預熱爐預熱爐用于加熱定型的金屬面到合適的溫度以確保聚氨酯混合物均勻平整地膨脹。金屬面的溫度控制對確保高質量的發(fā)泡板材是至關重要的。不合適的溫度可能會導致發(fā)泡密度的分配不均以及聚氨酯和金屬面之間缺乏粘性。最好使用熱空氣循環(huán)加熱爐。5計量設備可使用低壓或高壓的計量設備。

9、與低壓機相比高壓機主要有以下優(yōu)點：- 更好地混合原料；- 更小巧的混合槍頭；- 可在有限的地方安裝；- 在生產結束后不用清潔劑（環(huán)保的清潔劑）清洗；混合系統(tǒng)包括一個低壓預混裝置和對多元醇進行計量，然后采用高壓計量裝置，但是比較貴。這兩種系統(tǒng)共同的優(yōu)點包括：- 高效監(jiān)控所有的工作參數；- 由于使用專門的設備才能根據現行的法規(guī)，使用環(huán)保的發(fā)泡劑替代氟里昂11。 6反應混合料分配裝置一個可以使槍頭前/后移動的傳動機構，因此能夠平穩(wěn)均勻地澆注混合物到較低的面層上。由于使用了澆注范圍更廣的噴嘴因而在混合物膨脹的過程中避免了斑點、氣泡和泡沫的重疊。一個堅固的支撐架使得槍頭可以根據不同的生產需要進行高速的轉

10、動和傳送。如果是軟面層需要使用一個噴注板；它必須被加熱使軟面層獲得合適的溫度而有良好的粘性；而且在板的下面有一個抽氣機，通過復孔可以看見它，這樣可確保在層壓機進口處的軟面層有最好的平整性。7. 軟面層開卷機根據生產線的不同需要，可以選擇生產金屬面層、金屬/軟面層、或是紙/紙面層的不同板材，生產線可以配備開卷機在低、高層上生產軟面層。在高速生產以及需要不停產生產中，推薦使用帶有雙開卷機的系統(tǒng)（當一個開卷機工作時，另一個可作替補或被修理），帶有快速切換裝置。8雙履帶雙履帶系統(tǒng)包括聚氨酯泡沫發(fā)起過程和緊接著的固化階段。除成型壓力機之外，雙履帶兩面的金屬履板都采用內連接，這樣可使帶有滾軸軸承的鏈條有著

11、更高的承載能力。板材停留在雙履帶上的時間是根據使用的原材料和預先設置的板材厚度。40 mm厚的板材需要大約23 min的停留時間。oms公司制造的雙履帶從最短的15 m長到最長的38 m長。標準寬度為1200 mm，兩履帶的相間距離從20 mm到400 mm。生產不同厚度的板材需要在打開的履帶上插入校準的墊圈。當下層履帶被固定，一系列的液壓氣缸驅動上層履帶的移動。雙履帶由兩個獨立的電機驅動，電機帶有動態(tài)速度反應器，每一個都帶有相應的電機減震器以確保雙履帶間最好的速度同步。9板材輪廓（板型）改變系統(tǒng)采用這種簡單而有用的系統(tǒng)是經過特別研究那些可能的不同措施以縮短改變板材的時間。金屬履板帶有特殊的軌

12、道，軌道上能夠準確地插入帶有不同形狀的鋁板，相關形狀是依照所要生產板材的類型（屋頂 墻面）而定。在邊擋處，這些鋁板都帶有小洞以固定鋁質的嵌入物。需要提醒的是完全改變板材的輪廓要耗費60至90 min時間，具體根據雙履帶的長度而定。10板材切割機在進入切割機以前，一個可自由轉動的滾子傳送器傳送聚氨酯板材，給予其足夠的時間（幾秒鐘）使泡沫穩(wěn)固；只有這樣才能切割出所要的板材長度。也可以預先設置所要切割的長度和所需生產的板材數量；一旦達到預設置板材的數量，一個電子定時器將自動設定一個新的預設置長度和相應的切割數量。專門為軟面層所設計的切割機有著不同于金屬硬面層板材切割機的機械參數。這些設備有：圓盤式切

13、割機,帶鋸式切割機。11板材卸料和打包線在標準的連續(xù)板材生產線末端都帶有一條卸料和打包線，并可根據板材的尺寸儲存所有的板材。所使用的系統(tǒng)不同，設備的投資也不同：手動型，非常經濟；半自動型，中等投資；全自動系統(tǒng)非常貴。板材的卸料系統(tǒng)是根據板材的產量和所要生產板材的寬度。oms公司推薦兩種不同的系統(tǒng)：滾子式系統(tǒng)和旋轉籠式系統(tǒng)。1.2 使用戊烷作為替代發(fā)泡劑的標準聚氨酯生產設備的主要特征戊烷替代了氯氟化碳，它以前在不同種類的聚氨酯硬泡生產中作為發(fā)泡劑。使用戊烷的危險在于它在室溫中有著極高的可燃性，當空氣中戊烷氣的含量較高時就能引起氣體爆炸。事實上，空氣中戊烷氣的體積百分比為1.4%(低爆炸限制)到8

14、.1%(高爆炸限制)，任何的可燃源(火星、火苗和高溫)都會引起爆炸。因此，所有使用易爆氣體的機器和設備在生產時必須采用合適的技術手段預防：減小爆炸混合氣的危險，消除所有可能的危險因素。技術手段主要包括：(1)特殊安全法規(guī)下的電路按照現行的法規(guī)，所有用于或位于危險區(qū)域的電路必須遵照特殊的技術說明。根據i.e.c. 79-10國際標準，根據危險物質的數量，生產過程和環(huán)境溫度等劃分所有危險的設備區(qū)域；危險區(qū)域的面積被預先計算。電路的類型和最終通風系統(tǒng)的尺寸，都被取決于以上數據，其中通風系統(tǒng)主要是為了減少危險區(qū)域的面積。所有在危險區(qū)域的電器元件都要按照防爆安全法規(guī)執(zhí)行。(2)生產安全防范為減少可燃源，

15、在機器和設備的生產中執(zhí)行相關的安全措施：- 所有設備的金屬元件都要有接地系統(tǒng)；- 使用無靜電的裝置/元件；- 所有的管子都是等位連接；- 通風系統(tǒng)可降低危險區(qū)域的警報極限；- 戊烷氣探測系統(tǒng)通過傳感器探測；- 氮氣系統(tǒng)用于覆蓋儲存和/或多元醇/戊烷的儲罐；- 用于儲罐的防火系統(tǒng)。1.3 應用在使用戊烷作為替代發(fā)泡劑的標準聚氨酯生產設備上的安全措施在使用戊烷的機器和設備上采用以下安全措施：- 在設備內關鍵處裝有帶有聲音和可視警報的戊烷泄漏探測系統(tǒng)；- 警報信號系統(tǒng)帶有兩級警報：1級警報：聲音和可視警報并有相關的按鈕停止機器或設備；2級警報：聲音警報并且切斷機器或設備的電源；- 萬一戊烷氣泄漏，緊

16、急制動按鈕將切斷/停止生產線；- 萬一戊烷氣泄漏，通風系統(tǒng)會增加抽風的能力；- 監(jiān)測系統(tǒng)和通風系統(tǒng)相結合；- 切斷所有在警報區(qū)域中電路的電源；- 對所有主要泄漏源的不斷監(jiān)測；- 所有戊烷進料管的進口處都裝有安全閥；- 防火系統(tǒng)；- 通風系統(tǒng)和氣體探測器帶有備用電機。2 高速層壓機在美國安裝了一條用于生產軟面層pir硬泡絕熱板材的連續(xù)生產線，它是根據一個新的生產理念開發(fā)的，因而代表了世界上最先進的連續(xù)生產線。2000年7月正式投產，這條生產線可以以60 m/min的速度生產板材（舉例來說，如果實際板寬1.2 m，那就是72 m2/min）。這一先進技術的設備包括：* 30m長，60 m/min工

17、作速度（實際生產速度）的雙履帶；* 可生產的板厚：范圍從10 mm到220 mm；* 可以生產坡度形（板材截面漸變）板材（最大傾斜為60毫米）；* 由于在雙履帶上應用了建設性的創(chuàng)新理念，因而可實現同步自動調整板寬；* 雙履帶的加熱系統(tǒng)溫度可達+80可以加工pir泡沫即使在高反應情況下；* 可以覆蓋整條雙履帶的圍房由自承式絕熱板材建成，能夠容納最終散熱系統(tǒng)；* 多元醇+戊烷的計量和混合設備包括三個高壓計量組，每一個都配備質量型流量計；這套設備即使使用市場上提供的替代發(fā)泡劑也可正常工作* 閉環(huán)控制系統(tǒng)控制所有的工作參數（計量泵的輸出；溫度；工作壓力；生產速度等）；* 設備的控制與一臺工業(yè)用pc（個

18、人電腦）完全的結合以操作和控制整條生產線；* 安全和通風/抽風系統(tǒng)通過足夠的傳感器和相關的抽風設備監(jiān)測所有的工作區(qū)域，這樣就能安全的使用易燃發(fā)泡劑（環(huán)戊烷，正戊烷，異戊烷等）。傳統(tǒng)層壓機和高速型層壓機（至少50m/min）的不同之處歸納起來有以下幾點：l 在軟面層的生產中，一個帶有快速切換裝置的雙開卷機（用于上下面層）是必須的。如果只配有一個開卷機，雖然換紙或鋁箔的時間是相同的，但是由于面層材料的消耗很大，所以更換的次數會非常頻繁。l 相對傳統(tǒng)的生產線，由于高速生產線的原料消耗很高，它的計量設備組需要更大的原料輸出；而且，所有的計量線都需要配有帶有閉環(huán)控制系統(tǒng)的質量型流量計，否則不連續(xù)控制所有

19、的工作參數會對總的輸出控制產生干擾。l 澆注導軌上只帶有一個能擺動的混合槍頭在高速澆注時是不起什么作用的；從機械的角度看，槍頭的移動是可以達到的，但是高速澆注是非常不準確的，其澆注材料的慣性會使材料從澆注臺中濺出；所以高速澆注的唯一解決方法就是使用兩個或三個固定的帶有澆注分布器的混合槍頭；每一個槍頭可以調整其在澆注臺上的高度和位置；三個（兩個）混合槍頭可以滿足三個（兩個）不同的獨立計量線的需要。l 雙履帶的結構沒有改變，但是它的長度不能少于30 m，否則發(fā)起的聚氨酯泡在層壓機上的停留時間會太短，這樣發(fā)起的厚度就會不同。l 整個的切割，儲存和打包線都必須達到與傳統(tǒng)生產線相同的準確度和精度。3 結

20、束語連續(xù)的層壓機在過去的幾年里應用非常普遍，因為聚氨酯和pir被視為是其他絕熱材料很好的替代品，它大大減小了建筑業(yè)中所用墻面的厚度。在連續(xù)生產線上使用的戊烷成功地替代了所有以氯氟化碳為基礎的發(fā)泡劑，因而高聚氨酯消耗的技術轉變成為了環(huán)保的生產過程。在任何情況下，我們都必須認識到使用戊烷的生產線需要特殊的結構、生產設計和加工工藝技術。另外，我們還要特別注意人員的安全以避免受傷，安全地操作機器并注意有關的環(huán)境問題。對高速層壓機的需求實際反應了大生產規(guī)模的需要，這也對設備的制造商和夾心板的生產者提出了有趣的挑戰(zhàn)。新技術已經誕生了，需要做的是符合使其走向成熟的要求。pu continuous panel

21、 line with flexible substrata technologygiorgio pallanza (oms group, italy)abstract: the standard structure of a continuous pu panels plant is substantially replied in a high speed lamination process. the main modifications take place into: 1) substrata uncoilers, which must be double with rapid cha

22、nge of the substratum tool; 2) metering group, slightly oversized and replicated to meet the requirements of bigger output requested; 3) pouring plate and reactive mix distribution; a single oscillating mixing head is not able to guarantee the homogenous and laminar pouring on the substratum and is

23、replaced by a multiple mixing head; 4) the double belt conveyor needs a length not lower than 30 meters; 5) the cutting, stacking and packing line are engineered to work at high speed. continuous lamination has become very common in the last years, since the insulation with pu and pir is now seen as

24、 good alternative to other insulation materials and allows a substantial wall thickness reduction in the building industry. the use of pentane in continuous plants has successfully replaced all other cfc-based blowing agents, thus transforming a technology with high pu consumption into an environmen

25、tal-friendly process. the step to high speed lamination has become necessary for high production requirements, and has represented an interesting challenge both to plant producers and to direct sandwich panels producers.keywords: sandwich panel; faced material; polyurethane panel; production equipme

26、nt; continuous panel line作者簡介：giorgio pallanza 1972出生，化學工程博士，曾任聚氨酯組合料技術市場經理，2001年加入oms公司，目前是該公司遠東市場銷售經理。pu continuous panel line with flexible substrata technologygiorgio pallanza(oms group, italy)abstractthe standard structure of a continuous pu panels plant is substantially replied in a high speed

27、 lamination process. the main modifications take place into: 1) substrata uncoilers, which must be double with rapid change of the substratum tool; 2) metering group, slightly oversized and replicated to meet the requirements of bigger output requested; 3) pouring plate and reactive mix distribution

28、; a single oscillating mixing head is not able to guarantee the homogenous and laminar pouring on the substratum and is replaced by a multiple mixing head; 4) the double belt conveyor needs a length not lower than 30 meters; 5) the cutting, stacking and packing line are engineered to work at high sp

29、eed. continuous lamination has become very common in the last years, since the insulation with pu and pir is now seen as good alternative to other insulation materials and allows a substantial wall thickness reduction in the building industry. the use of pentane in continuous plants has successfully

30、 replaced all other cfc-based blowing agents, thus transforming a technology with high pu consumption into an environmental-friendly process. the step to high speed lamination has become necessary for high production requirements, and has represented an interesting challenge both to plant producers

31、and to direct sandwich panels producers.continuous production of sandiched panels using rigid and flexible substrata: a step from conventional to high speed processesproduction technologies for continuous panels linesthe application of polyurethane foams in the industrial and building insulation fie

32、lds is one of the leading production sectors in which it was has invested considerable time and effort. thanks to their particular properties and their versatility, rigid polyurethane foams have become widely used in these application fields.the production processes adopted to produce panels are div

33、ided into continuous and discontinuous process. both processes have been successfully implemented with expanding agent alternative to freon 11 family, mostly with pentane and other environmental-friendly blowing agents.continuous processthe continuous panel production process is certainly the most c

34、onvenient for quality and quantity standards achieved.this technology is suitable large for the large scale production of high quality panels with either rigid or flexible substrata.a standard, conventional, fully integrated continuous panels production plant is composed of:(1) rigid substrata uncoi

35、lers, (2) loading coil cars, (3) roll forming unit, (4) pre-heating oven, (5) metering machine, (6) reactive mixture distribution, (7) flexible face uncoilers unwinders, (8) double conveyor belt, (9) panel profile change-over system, (10) panels cutting unit, (11) panels unloading and stacking line.

36、 (1) rigid substrata uncoilersuncoilers support and guide the sheet layer coils towards the roll forming machine to be shaped.the uncoilers are two: one for the lower sheet layer and the other for the upper sheet layer.a double metal uncoiler is optionally added to the first one, allowing a minor nu

37、mber of production breakouts.(2) loading coil carsloading coil cars are used to position the sheet coils on the uncoilers.the coils can be set on the uncoilers even by using a fork-lift only on low speed production plants. for more sophisticated plants loading coil cars are necessary. coil cars in s

38、teel structural frame-work fitted on an hydraulically driven sliding support. a v shaped platform is moved upward and downward by a hydraulic cylinder for coil loading.(3) roll forming unitchoosing the right roll forming unit is dictated by both the types of panels to be produced and the financial i

39、nvestment on the plant.the configuration of the roll forming unit relies on the type of panels to be produced:corrugation depth, design of the profile, max width of the panel and detail joint designed of the panel (male/female; secret fix joint; cold store joint).(4) pre-heating oventhis pre-heating

40、 oven heats the profiled metal sheets to the right temperature to ensure the even and smooth expansion of the polyurethane mixture. the temperature control of the metal sheets is extremely important to ensure a high quality foamed panel. an unsuitable sheet temperature may cause a different foam den

41、sity distribution and lack of adherence between polyurethane and metal sheets.a hot-air circulation oven is the best to be used.(5) metering machinea metering machine can be either low pressure or high pressure.the main benefits offered by a high pressure metering machine compared with a low pressur

42、e one are:- better mixing of the components;- compact dimension of the mixing head resulting thus in:- positioning in restricted spaces;- solvent-free cleaning at end of production (environmental friendly solution)an hybrid system, composed by a low-pressure premix and metering in the polyol followe

43、d by a high pressure metering/impingement is a possible solution, but more expensive. in any case it allows the same advantages of both systems, including:- high efficient monitoring of all working parameters;- possibility to use, according to the present regulation in force, blowing agents alternat

44、ive to freon 11 thanks to dedicated instruments(6) reactive mixture distributiona traverse provides a backward/forward movement to the mixing head thus enabling a smooth and even distribution of the reactive mixture all over the lower substrata, thanks to a wider range of nozzles thus avoiding splas

45、hes, air bubbles and foam superimposing during the rise phase.a robust structural support framework permits high reversion and translation speed of the mixing head according to the several production needs.a pouring plate is necessary in case of flexible substrata; it must be heated, to give the sub

46、strata the right temperature for a correct adhesion; moreover a suction under the plate is foreseen (through multiple holes), in order to ensure the best flatness of the substrata at the entrance of the laminator.(7) flexible face uncoilers unwinders.depending on the manufacturing flexibility of the

47、 plant which can alternatively produce metal faced panels, metal/flexible face, or paper/paper, the plant can be equipped with uncoilers for flexible sheets both on the lower and upper layer. for high speed processes and for plants which requires no-stop production, it is recommended a system workin

48、g with double unwinders (while one is working the other can be substituted and fixed), with rapid change device.(8) double conveyor beltthe double conveyor belt contains the foam rise during the expansion and subsequent curing phase. besides forming the press planes, both metal slats are inter-conne

49、cted in order to have a high load bearing chain complete with side rolling-bearings.the time the panel stays on the conveyor depends on both raw materials used and pre-set panel thickness: for a 40mm panel thickness it takes around 2 - 3 minutes.oms group has built conveyor belts ranging from a mini

50、mum of 15m up to a maximum of 38m total length. the standard width is 1200mm, the distance between the two conveyors planes ranges from 20mm up to 400mm.the variation in thickness of the panel to be produced requires the insertion of calibrated spacer rings at open conveyors. the upper conveyor is m

51、ovable by a series of hydraulic cylinders, while the lower one is fixed.the two conveyors are driven by two independent c.c. motors fitted with dynamic speed reaction, each one complete with relative motor reducers in order to ensure a perfect speed synchronization between the two conveyors.(9) pane

52、l profile change-over systemit has been paid particular attention to the study of different possible solutions to minimize the change-over time by adopting simpler, functional systems. metallic slats have special guides which allow the insertion of accurately machined aluminum slats having a differe

53、nt profile according to type of panel (roof - wall) to be produced. for the side containment, these aluminum slats have holes to fix the aluminum inserts.it should be noted that a complete change of the panels profile may involve a loss of time ranging from 60 to 90 minutes depending on the length o

54、f the double conveyor belt.(10) panels cutting unit before reaching the cutting unit, a free-turning roller conveyor houses the pu panels for enough time (few seconds) to achieve a foam stabilization; only afterward it is possible to cut the panels to the desired length.it is possible to pre-set bot

55、h the desired cutting length and number of panels to be produced; once the pre-set panels number is reached, an electric timer fixes automatically a new pre-set length and relative number of cuts to be effected.the cutting units dedicated to flexible substrata have completely different mechanical fe

56、atures from the ones used for cutting metal faced panels.these units can be either: - circular disk cutting machine; - band-saw cutting machine.(11) panels unloading and stacking linea standard continuous panel production plant ends with an unloading and stacking line storing all panels according to

57、 their length.the investment this equipment requires may vary according to the type of systems adopted: manual, very economical; semi-automatic, average investment, and completely automatic system which is quite expensive.the panels unloading system depends on both plant productivity yield and width

58、 of the panels to be produced.oms group proposes two different systems:- rollers system;- rotary cage systemmain characteristic of a standard polyurethane production plant using pentane as alternative blowing agentpentane has replaced chlorofluorocarbons (cfc) once used as blowing agents in the production of several different kinds of polyurethane foams.the hazard in using pentane lies in its highly flammability at room tem