造纸毛毯Appita Pres

Solutions: 對策 (a) make the felt more open. 使毛毯更加開放通暢 (b) Increase the bulk to extend the useful life. 增加毛毯的鬆度來延長使用壽命 (c) Maintain felt conditioning equipment. 維修保養毛毯的清潔設備
IMPORTANT FELT DESIGN CONSIDERATIONS 毛毯設計的重要考量
Type of machine and paper grades produced. 紙機的種類和生產紙種 Machine speed. 紙機速度 Quality and type of stock. 漿料的種類和品質 Position on the machine :- 紙機的各部位名稱 e.g. Pick-Up / Press / Top or Bottom Press configuration :- 壓水部的結構配置 Straight through / Bi Nip / Tri Nip. Press loading :- 壓力的負荷 Roll material and hardness. 轆的材質和硬度 Sheet run geometry. 紙張的運轉幾何 Cleaning equipment available :- 可利用的清洗設 備 High pressure showers. 高壓噴淋管 Dewatering equipment :-脫水的設備 Uhle boxes. 抽吸箱
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Make a heavier bulkier felt. 增加毛毯的基重或厚度。
PRODUCTION FLOW PRESS FELT PRESS FELT PRODUCTION HDP FELTS PRODUCTION
Production flow Fibres .. Monofilaments Multifilaments Twisting Weaving preparation Weaving Base fabrics Burling & Joining Blending Batt preparation Needling Finishing Final inspection Other presentation
BASE FABRIC PROPERTIES 基部的特性
Weight in GSM. 基重 Void Volume: 空隙比例 Loaded. 加負載/已植毛
Unloaded. 未負載/未植毛 Permeability. 透氣度 Caliper 厚度 Loaded. Unloaded. Hysteresis. 延滯性 延滯性 兩張均經過調濕處理的紙，但其中一張 低於而其另一張高於水份含量平衡點。
FELT BASE FABRIC YARNS 毛毯基部的紗線
MD & CD YARNS 縱向和橫向的紗線 Single Polyamide Monofilament. (Various Diameters) 聚醯胺單絲線 (不同的直徑)
Cabled Polyamide Monofilament. 整束的聚醯胺絲 線 2 x 2 of 0.20 mm 2 x 3 of 0.20 mm 2 x 5 of 0.20 mm Plied polyamide Multifilament.整股的聚醯複絲線
BATT FIBRE 植毛纖維
Usually Polyamides. (Some wool) 通常是PA的材質(些許羊毛) Comes in a range of fibre lengths, typically 80 - 115 mm long. 典型的纖維長是80-115毫米 A range of fibre weights, fine to coarse decitex, such as :- 4.2, 6.7, 17.0, 22, 44 and 67. (including various blends) 纖維重量的範圍，從細緻的到粗糙的decitex ，如4.2, 6.7, 17.0, 22, 44 和 67( 4.2, 67(包括各種的 混合) Batt fibre of the specified type and weight is needled onto the sheet and backside of the base, to provide the desired specification. In general, the batt is stratafied to suit the position. ie : Typically finer sheetside fibre and coarser fibre in the substrate and back side. 特有種類和重量的植毛纖維是針織在基布的 紙 面和運轉面，來提供所需求的規範。通常來 說 ，植毛層是來看部位搭配的。典型的範例：紙 面是較細緻纖維，運轉面是較粗糙的纖維 。
BURLING AND JOINING (Base fabric)
BATT PREPARATION (Fibre batt) NEEDLING (Needled felt)
FINISHING (Heat setting, Treatment, Precompaction, etc.) FINAL INSPECTION
The selected yarns are woven into a structure having a defined mesh count, caliper and permeability. Press felts are woven in an endless loop at a size to suit the specific application. 這些挑選過的紗線，編織成一個清晰的篩網數、厚 度、透氣度。壓水毛毯是以此編織成一個無接縫的 環，來適合這個特定的規範。
PRODUCTS AND APPLICATIONS. 毛毯的應用與製造
REQUIREMENTS OF A FELT 毛毯的功用
Support the sheet from the Fourdrinier through the Presses to the Dryers. 支撐紙張從網部，能順利的通過壓水部到烘缸部 Act as a drive belt to the undriven rolls of the felt run. 扮演著輸送帶的角色 Support the sheet in the press nip. (To prevent crushing) 支撐紙張通過捏縫(預防壓潰) Provide uniform pressure across the nip. (Bridge suction holes and grooves.) 提供一致的壓力來通過捏縫(使渡過抽吸孔和溝槽) Absorb water expressed from the sheet in the nip 吸收水分在通過捏縫時壓榨出來 Give the sheet a suitable finish. 給予紙匹適當的潤飾
隨著毛毯的運轉和緻密化，表面狀態和攜水能力有所改善，
讓揭紙較容易。 (如無法順利接紙, 會先下降車速, 等到揭紙正常後再拉車速)
SHEET BLOWING/FLUTTERING 紙匹包風和飄動的問題
Localised accumulation of air between felt and paper. 在毛毯和紙匹中，空氣局部性的累積 (該部位會出現摺痕且纸和毛毯的貼附性會不好) Common to Presses/Dryer Cylinders. 在壓水部和烘缸部很常見 Two possible causes: 兩個可能的原因 (a) (b) the felt is too dirty . 毛毯太髒 the felt is too thin & hard. 毛毯太薄或太堅硬
IMPORTANT FELT PROPERTIES. 重要的毛毯特性
Felt weight in GSM. 毛毯的重量 Void Volume. 空隙比例 Air Permeability. 透氣度 Water Permeability. 透水度 Strength. 強度 Size stability. 尺寸的穩定度 Wear resistance. 抗磨損能力 Compaction resistance. 抗緻密的能力 Contamination resistance. 抗髒污的能力 Surface characteristics. 表面的特性
RAW MATERIAL (Fibres, Yarns, Twists, Chemicals) SPINNING (Spun yarn) TWISTING (Twists)
WEAVING PREPARATION (Warp and weft) WEAVING (Base fabric endless, open)
Straight Through
Bi-Nip
Tri-Nip
IMPORTANT PRESS POSITION BACKGROUND INFORMATION 壓水部重要的背景資料
Previous felt performance. 之前的毛毯實績 Are there size constraints ? 是否有尺寸的限制? Reasons for removal - 移除的原因 plugging / compaction / wear ? 阻塞/緻密/磨 損 Is sheet pick-up a problem ? 是否有揭紙的問題 Is sheet stealing a problem ? 是否有偷紙的問題 Is sheet blowing a problem ? 是否有包風的問題 Is felt mark critical ? 毛毯的痕跡是否很關鍵(兩面 性) Is sheet prone to shadow or groove mark ? 紙匹是否易於產生陰影痕或溝紋痕 Is the position prone to :vibration, wad burn, or felt creasing ? 毛毯是否易於 震動、濕燃、產生摺痕?
濕燃 紙機壓水部有斷紙發生時，如有一團紙斷卡 在捏縫前，其摩擦所生的熱足與目前較為普遍之合 成纖維纏結而使毛布局部失去脫水作用。
SHEET PICKUP
Design Trade-off: 設計的妥協 Felt must be open enough so that the vacuum in the pick-up roll can effectively lift the sheet from the fabric. 毛毯必須夠開放通暢，以利揭紙轆的真空足以將紙匹從網部剝離 Yet closed enough to provide the adhesive force (surface tension) to hold the sheet to the felt. 毛毯本身也必須具有一定的緻密性，來提供紙匹在毛毯上的附著 力(表面張力) Pick-up Problems: 揭紙的問題 Too great a speed differential between the pickup and the fabric. 揭紙毛毯和塑膠網兩者之間巨大的速差 Old fabric / New felt - sheet will tend to follow the ‘smoother’ fabric. 舊網/新毯 – 紙匹會跟著較平滑的織物行走 More prevalent in early stages of felt installation - felt hasn’t ‘broken in yet’. 在毛毯安裝的初期，未到達最佳狀況是很普遍的情形。 (因毯較蓬鬆，含水量較高，速度上不來) As the felt runs in and compacts, the surface conditions and water-handling ability improve to give better pick-up.
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SHADOW/GROOVE MARKING 陰影痕和溝紋痕
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Problem particularly on coated grades. 問題特別容易出現在上膠或塗佈的地方。
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Can reduce the size of the suction holes in the bottom press roll. 減低下真空壓水轆真空抽吸孔的尺寸。