wet coat thickness
Wet coat thickness is the thickness of the adhesive layer immediately after application, before drying or curing, when all solvents and carriers are still present. It is a critical parameter for solvent-based and water-based coating processes, determining the drying load and influencing final dry coat weight. Wet thickness is always greater than dry thickness; the relationship is: dry thickness = wet thickness × solids volume fraction. Typical wet thicknesses for PSA applications range from 30 to 200 µm, depending on solids content. Online measurement is challenging; indirect methods using pump flow rate and line speed calculate wet coat weight, then convert using density. Optical sensors (laser profilometers) can measure wet thickness directly. Control of wet thickness is essential for consistent drying and to avoid defects like blistering or incomplete drying. Factors include adhesive solids, flow rate, line speed, and substrate absorption. Wet thickness monitoring provides fast feedback for flow adjustments, reducing scrap. It is particularly important for high-speed lines where drying oven response times are long.
Adhesive coating machine
Độ dày ướt là độ dày lớp keo ngay sau khi tráng, trước khi sấy. Lớn hơn độ dày khô. Quan hệ: khô = ướt × phần thể tích rắn. Điển hình 30-200 µm. Đo gián tiếp qua lưu lượng và tốc độ. Cảm biến laser đo trực tiếp. Kiểm soát độ dày ướt quan trọng cho sấy ổn định. Ảnh hưởng bởi phần rắn, lưu lượng, tốc độ, hấp thụ. Giám sát nhanh để điều chỉnh dòng, giảm phế liệu.
Natte coatingdikte is de dikte van de lijmlaag direct na aanbrengen, vóór drogen. Groter dan droge dikte. Relatie: droog = nat × volume fractie vaste stoffen. Typisch 30-200 µm. Indirecte meting via debiet en snelheid. Lasersensoren meten direct. Controle essentieel voor consistent drogen. Beïnvloed door vaste stoffen, debiet, snelheid, absorptie. Snelle feedback voor aanpassingen, vermindert afval.
ভেজা আবরণ বেধ হল শুকানোর আগে প্রয়োগের সাথে সাথেই আঠালো স্তরের বেধ। শুষ্ক বেধের চেয়ে বেশি। সম্পর্ক: শুষ্ক = ভেজা × কঠিন আয়তন ভগ্নাংশ। সাধারণত ৩০-২০০ µm। পাম্প প্রবাহ এবং গতি ব্যবহার করে পরোক্ষ পরিমাপ। লেজার সেন্সর সরাসরি পরিমাপ করে। সামঞ্জস্যপূর্ণ শুকানোর জন্য ভেজা বেধ নিয়ন্ত্রণ অপরিহার্য। প্রভাবিত করে কঠিন উপাদান, প্রবাহ, গতি, শোষণ। দ্রুত প্রতিক্রিয়া প্রবাহ সমন্বয়ের জন্য, বর্জ্য হ্রাস করে।
