GEA ONE 11TS, Инструкция по эксплуатации и техническому обслуживанию

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ONE 7TS – Maintenance
page 7.49
This manual is property of
GEA Niro Soavi S.p.A.
and no part of it may be reproduced.
DATA SHEET B: HOMOGENIZING ASSEMBLY
GENERAL
The homogenizing valve consists of 3 parts (with reference 7-24):
- passage
head
(1)
- impact head
(2)
- impact ring
(3)
.
Homogenization takes place during the passage between the opposite surfaces of the two heads, which
takes place at very high speed and is completed with the impact against the outer ring.
The phenomena that take place at very high pressure inside the homogenizing valve are very complex; in
general the micronization of the particles contained in the liquid can be described as the combination of tur-
bulence effects, cutting, localized cavitation and impact.
The three parts of the homogenizing valve, made of very hard, abrasion-resistant material, are normally sub-
ject to wear, the extent of which will depend on the type of product treated; on the surfaces we can see the
signs left by these phenomena:
- radial grooves starting from the inner diameter
(4)
;
- small craters near the outer diameter
(5)
;
- large craters and wear near the inner diameter
(6)
.
When the grooves due to wear become marked and reach the outer diameter, homogenizing efficiency is
reduced.
Therefore you should replace the components when the groove reach approximately 3/4 of the dimension or
when you feel that homogenizing efficiency is reduced.
In some cases components wear may make it impossible to reach the required operating pressure, so the
homogenizing valve has to be replaced.
Localized cavitation phenomena can create craters and marked grooves on the surfaces of the valve; in this
case too you should replace the worn components.
As regards the impact ring
(3)
, it has the dual function of completing homogenization by impact and protect-
ing the body of the Homogenizing assembly from erosion.
Wear causes the formation of a groove
(7)
on its inner surface which affects homogenization.
We recommend replacing the ring when the groove reaches a depth of approx. 1 mm.