Relative humidity (RH) – a ratio of the amount of water contained in the air, to the maximum quantity of water that may contain. Air with 100% relative humidity – the so-called saturated air. The optimum relative humidity for humans and most production processes – 50-55%. Air at higher temperatures should contain more water to maintain the same relative humidity. If, for example, in the winter, the room is supplied from outside air, which has a temperature T = – 5? C and relative humidity rh = 80%, the water content in it is 2.59 g/m3.
After heating the air to room temperature, the contents of water it will remain the same (ie, 2.59 g/cm3), but the relative humidity drops to rh = 14%. Therefore, in order to bring the lost relative humidity to the required 50-55%, you should spray it an additional amount of water. Relative humidity in the production (printing, woodworking, textile, etc.) – quality and cost of production, health and health personnel. Losses caused by fluctuations relative humidity is so high that the problem in recent years have been paying attention. Overseas production facilities equipped with automatic humidification was common practice.
We consider this issue on the example of the print shop. Low relative humidity in the pressroom (less than 45%), leads to deformation of the edges of the paper in the foot because it dries, the appearance of feeding problems paper in the feeder and at conducting sheets through the print section. Low relative humidity promotes the formation of paper dust in the shop, and the dust is the main carrier of static charges. Sheets of paper stick together in the feeder, which leads to frequent stops printing machine, decreased productivity, increased consumption of basic printing materials. Relative humidity is printed impressions emanating from the offset printing machine is 45 60%, depending on the configuration of the printing and dampening devices. Once in the shop with a moisture content less than 45%, paper prints are beginning to dry rapidly, change dimensions, they there is static electricity, which impairs further processing sealed sheets. In order to maximize the use of printing presses is necessary to stabilize the humidity in the production indoor printer and keep it at 50 60%. What makes the maintenance of relative humidity at 50 60%? 1. Increased efficiency printing machine by stabilizing processes. 2. Reducing waste Paper and cardboard on coersion and salad to 5%. 3. Reduced time to coersion and salad, ie, increase the useful life of printing machines up to 20%. 4. Reduction of particulate air pollution in the shop as paper dust at this moisture is not flying. 5. Reduce static electricity, because it reduces the number of carriers (paper dust), increases the possibility of due to an increase electrical and air tokootvodyatsih devices. 6. Improvement of health workers and support staff, reducing fatigue and human morbidity. more>>