粉末噴涂與應(yīng)用課件

1、Introduction to Powder Coating粉末涂料介紹Introduction Metal Pretreatment for use withPowder Coatings金屬前處理Metal Pretreatment Metal Preparation金屬的處理Pretreatment is a process intended to prevent the corrosion of the painted metal.前處理是一種提高耐腐蝕的工藝Fe2 + O2 + H2O=RUSTIron reacts with oxygen and water in the atmo

2、sphere creating a powdery brown mess, not very ornamental, and continuous until no solid metal remains.鐵在空氣中會(huì)與氧氣和水反應(yīng)生成褐色的物質(zhì)Metal PreparationPretreatment Metal Preparation金屬處理Several methods of corrosion prevention can be used幾種防腐蝕的方法For Steel:鐵：Automotive applications 汽車業(yè) Primer : Underseals : Layer

3、s of Paint.Metal PreparationSeveral methoSeveral methods of corrosion prevention can be used幾種防腐蝕的方法For Steel:鐵：Architectural Applications 建筑業(yè)Galvanising : Anti Corrosive Primer* Galvanising covering with a layer of zinc.Metal Preparation金屬處理Several methods of corrosion pMetal Preparation金屬處理Metal P

4、reparationMetal Preparation金屬處理Several methods of corrosion prevention can be used幾種防腐蝕的方法For Aluminium:鋁：Aluminium oxidises to form a white corrosion product鋁被氧化后形成白色的物質(zhì)Architectural Applications 建筑業(yè) Anodise : Acid PrimersMetal PreparationSeveral methoMetal Preparation金屬處理Why Pretreatment ?為什么要前處理？

5、Powder coatings are used to enhance the appearance of buildings, machines, furniture,appliances:粉末涂料用于改善建筑，機(jī)械設(shè)備，家具，以及其它器具的表面：Designers and architects are searching to give distinction in terms of colour and effects.設(shè)計(jì)師和建筑師提供了包括顏色和效果在內(nèi)的標(biāo)準(zhǔn)等級(jí)The problem is that all paints are porous：所有的涂料均不同程度的存在會(huì)滲水的小孔

6、Metal PreparationWhy PretreatmMetal Preparation金屬處理Molecules of water and salt can penetrate through the paint film.When they reach the metal surface the effect is worse than if the metal is uncoated.The answer = Pretreatment水和鹽分子可以滲透漆膜，一旦它們與金屬表面接觸，產(chǎn)生的影響甚至比沒有噴涂還要糟糕。要解決這個(gè)問題就需要前處理。Metal PreparationMol

7、ecules of Metal Preparation金屬處理Pretreatment:前處理The chemical conversion of the metal surface before applying the powder coating.The metal then resists corrosion and the conversion permanently improves the adhesion of the coating.在使用粉末涂料以前用化學(xué)方法對(duì)金屬表面進(jìn)行處理，可以改善耐腐蝕性和增加涂層的附著力。Metal PreparationPretreatment:

8、Metal Preparation金屬處理The performance of the powder coating is only going to be as good as the metal preparation. We will cover three types of metal treatment systems粉末涂料的功能類似于金屬處理，我們將介紹三種的金屬處理方法 Iron Phosphate for Steel用于鐵系的磷酸鐵 Zinc Phosphate for Steel用于鐵系的磷酸鋅 Chromate for Aluminium用于鋁的鉻酸鹽Other syst

9、ems can be used and information is available.當(dāng)然還有其它處理方法Metal PreparationThe performanMetal Preparation Iron Phosphate金屬處理 磷酸鐵Metal pretreatment can be applied by spray or dipping.金屬前處理可以借助噴淋或浸漬In the case of iron phosphate the process could look like this:下面是磷酸鐵的工藝流程Stages 1, 2 and 3 can be either s

10、pray or dip步驟1，2和3均可采用噴淋或浸漬DRAINDRAINStage 1Clean&PhosphateStage 2RinseStage 3Rinse&SealWorkFlowMetal Preparation Iron PhospMetal Preparation Iron Phosphate金屬處理 磷酸鐵Typical 3 Stage System典型的3步驟流程Metal SubstrateSteel Phosphatising System金屬基材None Ferrous Clean and EtchStage time duration1 90 seconds不同步

11、驟所需的時(shí)間2 45 seconds3 30 secondsStage temperature 1，2和3步驟所需的溫度40 60oCDrying/干燥溫度100 120oCTypical concentration 2 3 % by volume典型的濃度Typical acidity典型的酸值pH 3.5 5.5Typical coating weight典型的膜重20 40 mg/ft.Metal Preparation Iron PhospMetal Preparation Zinc Phosphate金屬處理 磷酸鋅Zinc Phosphate process for steel t

12、ends to be more complicated磷酸鋅的工藝流程復(fù)雜一些Stage 1CleanStage 2RinseStage 3Phos-phateStage 4RinseStage 5RinseDRAINDRAINDRAINDRAINMetal Preparation Zinc PhospMetal Preparation金屬處理Dwell Time :Each stage depends on:各階段所需的時(shí)間，受下面的因素控制 The amount of pretreatment chemical dissolved in water溶于水的前處理化學(xué)藥品的濃度 The ag

13、e of the chemical化學(xué)藥品的有效時(shí)間Regular checking is required to give consistent good results at least twice per shift.通常要經(jīng)常檢查前處理的狀態(tài)一個(gè)班至少兩次Metal PreparationDwell Time :Metal Preparation Zinc Phosphate金屬處理 磷酸鋅Typical 5 Stage System典型5步驟流程Metal SubstrateSteel Phosphatising System金屬基材None Ferrous Clean and Et

14、chStage time duration1 90 seconds不同步驟所需的時(shí)間2 45 seconds3 60 seconds4 30 seconds5 30 secondsStage temperature溫度40 60oCDrying干燥溫度100 120oCTypical concentration典型濃度2 4 % by volumeTypical acidity1 = alkaline酸堿性2 = acidicTypical coating weight40 70 mg/ft.典型的膜重Metal Preparation Zinc PhospMetal Pretreatment

15、 - BS 3189 Type 3Spray Phosphate Plant 9 stage pretreatment九步法 Degrease脫脂 Rinse水洗 Rinse水洗 Rinse水洗Acid Etch (phosphoric acid)表調(diào)Zinc Phosphate磷酸鋅磷化 Rinse水洗 Rinse水洗 De-ionised water去離子水水洗 Dry 干燥Quality Standard BS6497參考英國(guó)標(biāo)準(zhǔn)BS6497Metal Pretreatment Spray 9 stMetal Pretreatment Quality Control金屬前處理 質(zhì)量控制T

16、itration Checks:檢測(cè)項(xiàng)目：1. Cleaner2. Rinses3. Acid Concentration4. Rinse5. Phosphate Concentration and coating weight7. Rinse8. ObservationsChecked at regular intervals during normal production and before production commences以上項(xiàng)目應(yīng)在生產(chǎn)過程中定時(shí)和生產(chǎn)前進(jìn)行檢驗(yàn)Metal Pretreatment Titration CMetal PretreatmentDry金屬前處理干

17、燥To ensure metal surface is dry ready for powder coating.在噴涂粉末涂料前必須保證金屬工件已經(jīng)完全干燥Drying oven -Phosphate PlantMetal PretreatmentTo ensure meMetal Preparation Chromate金屬處理鉻酸鹽For aluminium chromate conversion鋁鉻酸鹽處理British Standards exist for the conversion of aluminium BS 6496適用于鋁的英國(guó)標(biāo)準(zhǔn)BS6496The same conv

18、ersion can be used for Galvanised steel-BS 6497適用于電鍍鐵的英國(guó)標(biāo)準(zhǔn)BS6497Stage 1CleanStage 2RinseStage 3EtchStage 4RinseStage 5Chrom-ateStage6 7RinseStage 8DeminRinseDRAINDRAINDRAINDRAINDRAINDRAINMetal Preparation ChromateFoMetal Preparation Chromate金屬處理鉻酸鹽Typical 7 Stage System七步法Metal SubstrateAluminium /

19、Aluminium Alloys金屬基材Galvanised Steel Clean and EtchStage 1CleaningStage 2RinseStage 3Deoxidise metal surfaceStage 4RinseStage 5ChromateStage 6RinseStage 7Acidulated RinseStage Temperature80 100oCDrying90 95oCDo not overheat at the dry off stage干燥溫度不能過高M(jìn)etal Preparation ChromateTyMetal Preparation Ch

20、romate金屬處理鉻酸鹽Chromate conversion to Aluminium and Galvanised steel鉻酸鹽處理完鋁和電鍍鐵后的變化Yellow Chromate ConversionTypical Coating黃色鉻酸鹽的變化Weight (g/m2)Pale Yellow0.2 0.7Gold0.7 1.6Brown1.6 3.5Green mix chromate/phosphate0.5 2.0 For Powder Coating a lightweight coating is recommended In the range 0.2 2.0 g/m

21、2 應(yīng)用于粉末涂料，膜重一般在0.22.0g/m2Metal Preparation ChromateChSpraying and ApplicationofPowder Coatings粉末涂料的噴涂與應(yīng)用Spraying and Application粉末噴涂與應(yīng)用課件粉末噴涂與應(yīng)用課件Powder Application Systems粉末涂料的應(yīng)用系統(tǒng)Powder Application SystemsPowder Application SystemsFeed Systems粉末涂料應(yīng)用系統(tǒng)供粉系統(tǒng)Direct feed system from Drum to Gun.粉末涂料直接從

22、粉桶送至噴槍The system shown feeds 1 gun右圖是只供一個(gè)噴槍的直接供粉系統(tǒng)Powder Application SystemsDirePowder Application SystemsFeed Systems粉末涂料應(yīng)用系統(tǒng)供粉系統(tǒng)Direct feed system directly from a 25 kilo box.This system is set up to feed 2 guns.Used mainly in manual operations.右圖為直接從粉末涂料的包裝箱至噴槍的供粉系統(tǒng)。圖中的設(shè)備適用于兩把噴槍，通常用于人工噴涂。Powder A

23、pplication SystemsDirePowder Application SystemsFeed Systems粉末涂料應(yīng)用系統(tǒng)供粉系統(tǒng)Bulk feed system, powder is supplied in a fibre bag. Weight of powder up to 1,000 kilos per bag.Used mainly on automatic plants where colour change is limited.大型供粉系統(tǒng)，粉末涂料一般1噸一個(gè)包裝，用于自動(dòng)噴涂系統(tǒng)，限于換色較少的場(chǎng)合。Powder Application SystemsBulk

24、Powder Fluidisation Systems粉末涂料流化系統(tǒng)Dry air passes through a membrane giving the powder liquid qualities.干燥的空氣通過微孔板，使粉末涂料象水一樣流動(dòng)。The air must be dry and free from water and oil.空氣必須除水和油Powder Fluidisation SystemsDryPowder Delivery Systems粉末涂料的傳送系統(tǒng)Powder Delivery SystemsPowder Delivery Systems粉末涂料的傳送系統(tǒng)

25、Actual powder feed systemVenturi feed from fluid bed.右圖是用文氏管從流化床吸取粉末的送粉系統(tǒng)Powder Delivery SystemsActual Forces at work on the Powder ParticlesAt any one time 4 forces are at work on the powder particle as it travels from the gun to the earthed work-piece.粉末在離開噴槍到達(dá)工件時(shí)受4種力的影響Air Resistance Electrostati

26、c AttractionWeight (Gravity) Aerodynamic Force Forces at work on the Powder PPowder Charging SystemsThere are 2 major categories in charging of powder coating corona and tribo:粉末涂料主要有兩種帶電方法靜電/摩擦 Gun TypeCharge Location充電位置InternalExternalRemotePowder SupplyXXCorona靜電法Integrated GunPowder SupplyXXTri

27、bo摩擦帶電法XPowder Charging SystemsThere aCorona Charging Systems靜電帶電系統(tǒng)In this method, a high voltage generator is used to charge an electrode at the tip which creates an electrostatic field (or corona) between the gun and the work-piece.利用高壓電極使粉末帶電，并在噴槍與工件間形成電場(chǎng)External Charging System/外充電系統(tǒng)Corona Charg

28、ing SystemsIn thisCorona Charging Systems靜電帶電系統(tǒng)Corona charging- manual system/手動(dòng)槍- automatic system/自動(dòng)槍Corona Charging SystemsCorona Corona Charging Systems靜電帶電系統(tǒng)Internal Charging System內(nèi)充電系統(tǒng)Corona Charging SystemsInternaCorona Nozzle Systems靜電槍的噴嘴The type of product toBe coated will influence The n

29、ozzle to be used on theSpray gun, two types are shownCorona Nozzle SystemsThe type Corona Nozzle Systems靜電槍的噴嘴Conical Spray Nozzles used to give an evenly distributed film thickness over flat panels.圓錐型的噴嘴一般用于噴涂平面，并得到膜厚均勻的涂層。Interpon AF particle managed powder being applied on domestic appliances.右圖

30、為Interpon AF粉末涂料用于家用設(shè)備Corona Nozzle SystemsConical SCorona Charging Systems靜電帶電法 The high voltage power supply charges the electrode高壓發(fā)生器使噴槍電極帶電 The concentrated charge creates an electrostatic field帶上電荷后形成靜電場(chǎng) The electrostatic field causes the air to ionize and generate a corona靜電場(chǎng)使空氣電離形成電暈 The cor

31、ona emits electrons電暈放射出電子 The electrons are picked up by oxygen molecules forming negative ions這些電子借助氧分子形成負(fù)離子Corona Charging Systems The hiCorona Charging Systems cont.靜電帶電法 The ions follow the field lines負(fù)離子沿著電力線移動(dòng) The powder particles distort the field around them粉末涂料粒子使周圍的電力線產(chǎn)生扭曲 The distorted f

32、ield lines direct ions to the powder particles扭曲后的電力線引導(dǎo)離子被粉末涂料粒子吸附 The ions bombard the powder particles and transfer the electrons giving the particles a negative charge吸附的離子轟擊粉末粒子，并使其帶上負(fù)電，形成負(fù)極Corona Charging Systems contTribo Charging Systems摩擦帶電法Tribo electricity is generated by the friction of o

33、ne material on another.In Tribo charged spray guns, the powder rubs on a specially formulated and shaped surface which allows charge to transfer.摩擦帶電是通過不同物質(zhì)摩擦形成的，摩擦槍可以使粉末與特殊設(shè)計(jì)并有特殊結(jié)構(gòu)的表面摩擦而帶電Tribo Charging SystemsTribo elTribo Charging Systems摩擦帶電法Tribo Charging SystemsTribo Charging Systems摩擦帶電法Tribo

34、 nozzles in different configurations.不同結(jié)構(gòu)的摩擦槍噴嘴Tribo Charging SystemsTribo noElectrostatic Fluid Bed Systems靜電流化床法Electrostatic Fluid Bed SystemPowder Penetration粉末的吸附The picture shows the development of the corona (red dotted area).Articles passing through are charged with the negative ions (-).The

35、 charged powder particles are attracted to the earthed substrate.右圖顯示了電場(chǎng)，電力線，粉末的充電及被接地的工件吸附過程。Powder PenetrationThe picture Powder Penetration粉末的穿透Achieving penetration into deep recesses in most important when applying powder coating.粉末涂料能否到達(dá)死角這對(duì)粉末涂料的應(yīng)用來說很重要The most effective controls are the nozzl

36、e patternAnd air assistance.有效的控制方法是選擇合適外形的噴嘴及調(diào)整輔助空氣It is possible to overcome the “Faraday Cage Effect”現(xiàn)在，克服“法拉第”效應(yīng)已成為一種可能Powder PenetrationAchieving pePowder Penetration粉末的穿透Reducing the “Faraday Cage” Effect減弱“法拉第”效應(yīng)To reduce the effect it is necessaryTo assist in the creation of charged airParti

37、cles inside the recess. This should be徹achieved by increasing the air stream.可以借助加大傳送空氣的壓力來減弱“法拉第”效應(yīng)Powder PenetrationReducing theFaraday Cage Effect“法拉第”效應(yīng)A Faraday cage can technically be defined as an area within which there is no electrostatic field.In finishing, this term is applied more loosel

38、y, and generally refers to an area such as inside corners or cavities that are difficult to coat.The reason why these areas are difficult to coat is that the adjacent surfaces to the inside of the corner attract the electrostatic filed, therefore deflecting the powder from penetrating into the reces

39、sed areas.At the same time , this recessed area is difficult for the aerodynamic forces to penetrate into without blowing powder off already coated areas.法拉第區(qū)域可以被認(rèn)為是靜電屏蔽區(qū)。實(shí)際應(yīng)用中定義更寬松，通常是指死角和洞等難噴涂區(qū)域。難噴涂的原因是這些區(qū)域的外圍吸引了電荷，這樣粉末就不能被吸附。 另外，從空氣動(dòng)力學(xué)來將，輸送空氣將粉末吹至這些區(qū)域也很難。Faraday Cage EffectA Faraday Back Ionisati

40、on反彈效應(yīng)A = powder attracted to the earthed componentB = build up to correct film thicknessC = ionised air within the powder film repels oncoming particles A = 粉末吸附在接地工件B = 形成合適的膜厚C = 在涂層上的離子云抵制吸附帶有同類電荷的粉末Back IonisationA = powder attrPowder Recovery Integrated System粉末回收系統(tǒng)Integrated Spray / Recovery

41、Booth System完整的噴涂/回收系統(tǒng)Powder Recovery Integrated SysPowder Recovery Systems粉末回收系統(tǒng)Typical cartridge back-Pulse cleaning design.Used in cartridge Recovery systems.典型脈沖自清理設(shè)計(jì)，通常適用于桶狀回收系統(tǒng)Powder Recovery SystemsTypicalPowder Recovery Systems粉末回收系統(tǒng)Cyclone Recovery SystemThe cyclone is used to separate the

42、powder particles from the air.The air is driven round the sides of the cyclone, reducing in velocity and releasing the powder to be collected at the base.Fine powder is usually transported out of the cyclone on the air flow.旋風(fēng)分離器根據(jù)粒徑分離粉末，空氣沿著旋風(fēng)分離器壁做圓周運(yùn)動(dòng)，速度漸漸降低，并釋放被收集的粉末至底部。細(xì)粉通常會(huì)隨流動(dòng)空氣離開旋風(fēng)分離器。Powder R

43、ecovery SystemsCyclonePowder Recovery Systems粉末回收系統(tǒng)Fine powder is collected on a filter system in the “after filters”. The pneumatic air pulse ensures air flow is consistent and the fine powder collected for disposal.細(xì)粉通過濾芯濾層被收集。有力的氣體脈沖保證了空氣流動(dòng)的連續(xù)性及需被分離的細(xì)粉收集。 Powder Recovery SystemsFine poPowder Reco

44、very Systems粉末回收系統(tǒng)A motor generates the air flow. Ensuring the correct air volume and velocity is maintained.電機(jī)提供流動(dòng)空氣，并保證氣體流量和速度。Powder Recovery SystemsA motorPowder in-line Sieving Systems粉末過篩系統(tǒng)Rotary In-Line Sieve旋轉(zhuǎn)篩Powder in-line Sieving SystemsPowder Vibrating Sieving Systems震動(dòng)篩Vibrating sievesa

45、re designed towork either:- Free standing- In-line震動(dòng)篩適用于：- 獨(dú)立區(qū)域- 流水線Powder Vibrating Sieving SystePowder Reciprocator Cycle粉末噴涂的往復(fù)機(jī)構(gòu)Cycle Rate往復(fù)速度=No. Of Guns x Pitch of Guns x 60噴槍數(shù)量x噴槍位置x60Conveyor Speed (mm/min)傳送鏈速度（毫米/分鐘）This will ensure striations do not occur on the components being coated.在噴

46、涂中要保證不要形成帶狀涂層。Powder Reciprocator CycleCycleApplication Practical實(shí)際應(yīng)用Application PracticalStoving and CuringofPowder Coatings固化爐及粉末涂料的固化Stoving and CuringTypes of Oven固化爐的類型 Convection energy is transmitted by air circulation to heat the components對(duì)流 熱量通過空氣流動(dòng)傳送，加熱工件 Radiation energy is transmitted d

47、irectly onto the parts without heating air between the parts and the radiation source輻射 熱量直接從輻射源被傳送至工件而無需空氣作媒體 Induction energy is transmitted through inducing electrical eddy currents that generate heat in the metal parts 感應(yīng) 熱量借助電流來傳送來加熱金屬工件Types of Oven Convection eneThe Baking Process固化過程The baki

48、ng stage, during which the powder coating melts, flows, gels and finally chemically reacts (cross-linking) and cures. It is critical to the performance of the coating that the temperature and time at temperature are maintained.Most baking ovens are designed to take the substrate through a pre-progra

49、mmed time temperature profile.固化過程包括粉末的熔融，流平，凝膠最后發(fā)生化學(xué)反應(yīng)形成涂層。固化溫度極其所占時(shí)間是非常重要的，大多數(shù)固化爐借助預(yù)先設(shè)置固化時(shí)間（溫度曲線）來設(shè)計(jì)。The Baking ProcessThe baking sPowder Application Radiation Stoving粉末的輻射固化Gas fires Infra-Red oven usedfor industrial components.左圖為用于固化工業(yè)用品的瓦斯紅外爐I-R emitters inside the oven cure the powder film when in direct line, as radiation energy.右圖為通過爐內(nèi)紅外發(fā)生器（熱源）固化粉末涂料I-R is often used to boost the curing in f