Watson-Marlow Bredel 265 User Manual
Page 17
DESCRIPTION
17
by means of a flange construction (C). A bearing-
mounted rotor (D) with two facing pressing shoes (E) is
in the center of the pump head.
In phase 1 the lower pressing shoe compresses the
pump hose by the rotational movement of the rotor,
forcing the fluid through the hose. As soon as the
pressing shoe has passed, the hose recovers to its
original shape due to the mechanical properties of the
material.
In phase 2 the product is drawn into the hose by the
(continuous) turning motion of the rotor.
In phase 3, the second pressing shoe will subsequently
compress the pump hose. Due to the continuous
rotating movement of the rotor not only new product is
sucked in, but also the already present product is
pressed out by the pressing shoe. When the first
pressing shoe runs from the pump hose, the second
pressing shoe has already closed the pump hose and
the product is prevented from flowing back. This
method of liquid displacement is also known as the
"positive displacement principle".
D
E
C
B
A