KSB 4K Series, Installation & Operating Manual

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4 Description
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4K / 4KD
▪ Bi-directional
▪
Multi-spring arrangement
▪ Balanced
4.5 Configuration and function
161*
471.01*
412.53**
562**
230*
523
412.52
412.51
474.51
914
477.51
472.51
475.52
Fig. 1:
Sectional drawing of a 4KD
161 Casing cover 475.52 Mating ring
230 Impeller 477.51 Spring for mechanical seal
412.51/.52/.53 O-ring 523 Shaft sleeve
471.01 Seal cover 562 Parallel pin
472.51 Primary ring 914 Hexagon socket head cap screw
474.51 Thrust ring
*: Required for the mechanical seal to function but not part of the KSB mechanical
seal
**: Not for nominal diameters 040, 050, 060, 070
Design
Mechanical seal for installation in pump sets and other rotating machinery in
accordance with the manufacturer's instructions.
4K and 4KD mechanical seals have been specially developed for use in pumps of the
KWP type series. The seal chamber of the pump is especially designed for installing
these seals.
Function
Primary ring 472.51, which is the axially movable sealing ring, is pressed to the
rotating mating ring 475.52 by springs 477.51. O-rings 412.51, 412.52 and 412.53 are
fitted for secondary sealing. Thrust ring 474.51 transfers the spring force and torque
from casing cover 161 via springs 477.51 and hexagon socket head cap screw 914 to
primary ring 472.51. Shaft sleeve 523, supporting mating ring 475.52, parallel pin 562
and O-ring 412.52, is clamped between impeller 230 and the shaft shoulder.
The 4K mechanical seal can optionally be used as a single mechanical seal or in a
double seal arrangement. The 4KD mechanical seal must be used in a double seal
arrangement. The use as a double mechanical seal requires seal cover 471.01, another
mechanical seal, further small parts for fastening and sealing, and a suitable barrier/
buffer fluid for the space between the two mechanical seals.
4.6 Flushing adapter
To prevent deposits at the outboard mechanical seal a flushing adapter can be
installed.