电泳涂装烘干系统简介中英对照版
Baking烘干
Proper baking is the final step in producing a quality electrocoat film. This procedure involves raising the vehicle to a sufficiently high temperature to cure all surfaces in a dirt-free environment.
适当的烘干是生产优质电泳漆膜的最后一道工序,这个工序既是将车身在无尘环境中升到足够高的温度,使所有表面固化。
Oven burners can transfer heat to the vehicle by two methods:
烘干炉燃烧器将热量传送到车身上是靠以两种常规方法:
High velocity convection is accomplished by circulating air through the oven and across the burners at high velocity to achieve rapid transfer of the heat to the vehicle. The rapid movement of the air across the body brings the metal to the curing temperature of the paint very efficiently. However, during the early curing stages, the paint film is quite sticky and will retain dirt particles which come in contact with it. Air filtration after the burner helps to maintain oven cleanliness. Regular periodic oven cleaning is necessary to remove dust accumulations which can be blown around by the convection air. Cleaning should include oven walls, floor, and air plenums; it can be done by sweeping, vacuuming, or washing.
高速对流,循环空气以高速度通过烘干室和穿过燃烧器,以达到向车身迅速地传递热量。空气通过对车身的快速流动将金属提升到能使油漆有效固化的温度。然而,在固化的最初阶段,漆膜相当粘,且会将与其接触的尘粒粘住,在燃烧器之后加空气过滤有助于保持烘干室的清洁度。定期地进行烘干室清理是必要的以除去可被对流空气吹起的沉积灰尘。清理要包括炉壁板,底板及风道,可以用清扫,真空吸尘或擦洗的方法进行。
Radiant heating is frequently used for heat transfer to the vehicle. In this technique, a special oven wall is heated several hundred degrees above the cure temperature of the coating. The heat is transferred to the vehicle by the same process whereby a heating lamp warms the human body. An advantage of this technique is that little air movement is required to promote curing of the electrocoat. Thus, little dirt is permitted to adhere to the sticky paint film. This method of radiant heating is used in the first 30- 40% of the oven to "skin" the paint and prevent it from picking up dirt in the more efficient convection zones of the oven.
辐射加热,常被用来向车身传热。在这种技术中,一特殊的烘干炉壁板加热到高于涂层固化温度几百度,以与加热灯为人体取暖同样的方式将热量传递给车身。这种技术的优点是可为促进电泳漆表面固化并只需要少量的空气流动,这样使粘到漆膜上的灰尘大大减少,在前端30~40%的烘干室长度内用辐射加热方法形成表面,以使漆膜“表面”在烘干室高效对流区不再粘上灰尘。
Completeness of cure is best determined by solvent wiping with methyl isobutyl ketone (MIBK). Ten double rubs with a clean cloth with MIBK should produce no discoloration on the cloth and no dulling of the rubbed paint. Incomplete cure can result in poor chip resistance for subsequent coatings and film distortions which cause poor appearance. Severe undercure of electrocoat can prevent additional coatings from curing. Heavy metal areas should be used for cure evaluation since they require more heat time for curing than do thin metal panels.
测定漆膜漆膜是否完全固化,最好的方法是用甲基异丁基酮(MIBK)溶剂擦拭。用干净的带有甲基异丁基酮的布在漆膜表面上往复擦十次,应不在布上染色,且被擦的漆面不模糊。不完全的固化会导致涂层的耐冲击性能不佳,漆膜变形引起的外观不良等。电泳漆严重固化不良时会阻碍后续涂层的固化。对厚金属板区的固化加热时间要比薄金属板区长,对厚金属板区工件要进行固化评定。因为厚板区宽固化加热时间要比薄金属区长。
Baked vehicles can be force cooled in an exhausted enclosure to prevent smoke in adjacent areas. High velocity ambient air directed at the body works well. Reducing the metal temperature to below 180 F . will minimize smoke evolution. The use of cool-off zones is not required for proper electrocoat performance and is usually dictated by the time from oven exit to the first manual sealer application. The use of cool-off zones, therefore, must be determined on an individual plant basis.
烘干后的车身可在排风的封闭间内强制冷却,以防烟雾弥漫影响邻区。室温空气高速对车身吹拂效果好,把金属温度降到180F以下,可将烟放出量减到最少。就电泳涂层特性而言,不要求用冷却段,一般都是根据从烘干室出口到第一个人工密封工位的时间提出要求。因此必须根据具体的工厂情况来确定。