We often say that spraying is a technical skill, but what exactly does it involve? As a qualified thermal spray engineer, understanding material properties and equipment performance is just the basics. The spraying process includes cleaning —— sandblasting —— tool protection —— spraying —— post-treatment. Let's break down the key considerations for each step.
1、 cleaning
When receiving products, we must first remove oil stains and rust. Only by thoroughly cleaning the workpiece can we ensure the adhesion strength of the coating—a fundamental requirement that determines bonding integrity. This critical yet often-overlooked step requires continuous monitoring after initial cleaning. While decontamination serves as the primary phase, a final inspection is essential before proceeding with spray application.
2、 sand blast
Sandblasting is employed to roughen surfaces, enhance bonding strength, and remove stubborn rust deposits. Various abrasive materials are used for this purpose, including white corundum, brown corundum, and steel grit. The selection of abrasive should match the substrate's hardness, while the required surface roughness must be determined by the desired coating thickness – higher roughness isn't always better. My experiments demonstrated that within an optimal roughness range, bonding strength remains consistent. However, when exceeding or falling below this threshold, the bonding performance decreases significantly.
3、Protection of workers
For the area not sprayed, it is also very important to protect it with appropriate materials and tools. On the one hand, it protects the workpiece, on the other hand, it prevents the spraying to other parts and leads to product failure. The design and production of tools also reflect the level of engineers. The design of simple and reasonable protective tools is also a responsibility to customers.
4、Spray processing
In spray coating processes, optimizing robotic programming significantly enhances efficiency while ensuring product quality. Programmatic flaws may cause localized overheating and excessive coating thickness, which can lead to cracking and peeling. Implementing targeted controls—including cooling mechanisms, rotational speed adjustments, and precise regulation of spraying distance and angle—helps maintain coating integrity. When these controls are improperly managed, the equipment's full potential cannot be fully realized.
5、Spray post-treatment
After spraying, some products need to be ground, turned and polished. Choosing the right processing method can also improve work efficiency and product quality.
The selection of spraying materials and process is only the first step of spraying processing, and the control of these processes can show the real strength of a spraying processing plant. Only by controlling every link can we ensure the stable quality and excellent performance of the coating.
VELAVISION has always been committed to improving product quality and customer experience, we pay attention to every link, so that the coating for customers' products provide better protection.