In all peristaltic pump heads, the size of the pump tube is proportional to the flow rate, and the larger size of the pump tube and the diameter of the rotor will produce a larger "fluid pillow" (the space for the fluid in a pump between the adjacent rollers in the pump head). The volume of the "fluid pillow" determines the flow of pump for each specific turn of the pump head
When the flow accuracy is high, it is necessary to use smaller tolerances and adjust the pump. The "smaller tolerance" means that the tolerance of the inner diameter and wall thickness of the pump tube is smaller than the manufacturing dimension, and this pump tube can reduce the difference of the flow between the channels. Adjusting the pump to adjust the locking degree of the pump tube can further reduce the difference.
All the material of the pump tube will be squeezed. During extrusion, the shape and flow rate of these pumps will change. The extrusion time and the volume of the pump will vary with the size and material of the pump. In the case of high flow accuracy requirement, the pump with new pump can be run for several minutes before adjusting the flow rate through each channel.