Tan Y M, Flynn M R
Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina at Chapel Hill, USA.
Appl Occup Environ Hyg. 2000 Oct;15(10):785-93. doi: 10.1080/10473220050129428.
The transfer efficiency of a spray-painting gun is defined as the amount of coating applied to the workpiece divided by the amount sprayed. Characterizing this transfer process allows for accurate estimation of the overspray generation rate, which is important for determining a spray painter's exposure to airborne contaminants. This study presents an experimental evaluation of a mathematical model for predicting the transfer efficiency of a high volume-low pressure spray gun. The effects of gun-to-surface distance and nozzle pressure on the agreement between the transfer efficiency measurement and prediction were examined. Wind tunnel studies and non-volatile vacuum pump oil in place of commercial paint were used to determine transfer efficiency at nine gun-to-surface distances and four nozzle pressure levels. The mathematical model successfully predicts transfer efficiency within the uncertainty limits. The least squares regression between measured and predicted transfer efficiency has a slope of 0.83 and an intercept of 0.12 (R2 = 0.98). Two correction factors were determined to improve the mathematical model. At higher nozzle pressure settings, 6.5 psig and 5.5 psig, the correction factor is a function of both gun-to-surface distance and nozzle pressure level. At lower nozzle pressures, 4 psig and 2.75 psig, gun-to-surface distance slightly influences the correction factor, while nozzle pressure has no discernible effect.
喷漆枪的转移效率定义为施加到工件上的涂料量除以喷射的涂料量。对这一转移过程进行表征有助于准确估算过喷产生率，这对于确定喷漆工接触空气中污染物的情况非常重要。本研究对一个用于预测高流量低压喷枪转移效率的数学模型进行了实验评估。研究了喷枪与表面距离和喷嘴压力对转移效率测量值与预测值之间一致性的影响。利用风洞研究以及用非挥发性真空泵油代替商用涂料，在九个喷枪与表面距离和四个喷嘴压力水平下测定转移效率。该数学模型在不确定度范围内成功预测了转移效率。实测转移效率与预测转移效率之间的最小二乘回归斜率为0.83，截距为0.12（R2 = 0.98）。确定了两个校正因子以改进该数学模型。在较高的喷嘴压力设置（6.5 psig和5.5 psig）下，校正因子是喷枪与表面距离和喷嘴压力水平两者的函数。在较低的喷嘴压力（4 psig和2.75 psig）下，喷枪与表面距离对校正因子有轻微影响，而喷嘴压力没有明显影响。
