1: Velocity: velocity is very low (less than 0.03/s), taking into account the equipment running smoothly and whether there is a creeping phenomenon. High speed (less than 0.8M/s), lubrication of the ink may be destroyed, seals are not good lubrication and friction and the heat, resulting in greatly reduced service life. Recommended rubber and plastic with seals in 0.3M/s~1.2m/s speed range is more appropriate. 2: temperature: low temperature will reduce the elasticity of rubber and plastic seals, causing leakage, and even the seals become hard and brittle. High temperature oil volume expansion, softened, resulting in rapid increase in seal friction resistance during exercise and reduced pressure. Recommended rubber composite sealing continuous working temperature -10~+80 degrees centigrade. 3: working pressure: oil minimum pressure requirements. Low voltage low friction properties. aerodynamic resistance of the oil seal. 2.5Mpa, rubber composite sealing was not right to consider when high pressure seal pressure, need anti extrusion ring grooves also has special processing requirements.