汽车涂装工艺任务B工序五教程.ppt

面漆层的涂装任务B 油漆流量 喷枪出漆量必须达到要求：调节后能够输送足够油漆，产生适当厚度的漆膜。 大多数生产用喷枪每分钟出喷漆量是300 - 400 ml 。 施工条件 汽车修补产品最佳使用温度是常温：18 - 25oC。 当施工温度偏离常温，可以用快干或慢干稀释剂和固化剂，保持产品的正常施工性能。 稀释剂的挥发速度 重要的是稀释剂的挥发速度必须与油漆中的溶剂匹配 稀释剂用量 稀释剂用量正确，油漆的粘度就合适，粘度合适有以下优点： 流平均匀、 遮盖力强、 节约油漆 闪干 / 表干时间 “闪干时间” 用于表面初始干燥速度很快的油漆，如双组份油漆、硝基纤维素漆等。 “表干时间” 用于表面干燥速度较慢的油漆，如醇酸树脂漆等。 表面温度 施工时油漆的温度很重要，油漆的温度必须与所喷涂的车板温度非常接近 喷涂顺序 (1人喷漆) 车门3应该打开，喷涂最后一块后叶子板时，不会产生干喷 喷漆的基本原则 喷漆并不难，只要您遵守喷漆的基本原则 To check a sprayguns fluid flow rate :- Place 1000 ml ( 1 litre ) of solvent in the gun cup. Adjust the gun fluid control to fully open. set the air pressure to 3.5 bar at the gun. Engage the trigger on the gun to fully open for 1 minute, and then release. Pour out the remaining solvent from the fluid cup and measure the volume. Subtract this quantity from the original 1000 mls, and the difference will be the amount of fluid the gun passes per minute. Note : Proper gun adjustment and spray technique does not guarantee that the paint product will atomise properly. In addition, proper atomisation depends upon other factors such as the viscosity of the product being used, and the volume of atomizing air. Refinish products demand certain requirements, if they are to be properly applied for lasting durability. Basically the bodyshop conditions must fit the product needs, in terms of temperature, ventilation, lighting, cleanliness, and equipment. 1. Shop temperature below normal If the temperature drops below a selected thinners range of evaporation, the thinners will cause the paint to be excessively wet, resulting in :- Sags / Runs Mottling of metallic colours miss match of colours Note: The normal responsive measure to avoid occurrences listed above is to alter the spraygun technique, by holding the gun further back from the surface and/or increasing the gun travel speed. Altering the techniques in this manner, applies less than the recommended film build per coat, which can result in sand scratches, dulling, miss match of colour and poor dur