4 Description
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4STQ
2580.821/04-EN
4.5 Configuration and function
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2
3
4
5
6
7
8
9
11
13
14
15
10
12
16
19
17
18
Fig. 1:
Sectional drawing
Design
Mechanical seal for installation in pump sets and other rotating machinery in
accordance with the manufacturer's instructions.
KSB’s mechanical seal 4STQ is a cartridge seal that has been especially developed for
use in pumps of the Sewatec, Sewabloc and Amarex KRT type series. KSB’s
mechanical seal 4STQ can only be operated with a non-pressurised buffer fluid. It is a
double mechanical seal. Its inboard seal is designed with an axially moveable primary
ring 4 and a mating ring 3, its outboard seal with an axially moveable primary ring 8
and a mating ring 7. The inboard seal provides sealing on the product side, the
outboard seal on the atmosphere side.
Function
The inboard seal and outboard seal are stationary seals with a rotating mating ring 7.
The rotating rings are in contact with the stationary primary rings 4 and 8 and form a
sealing clearance. The springs 15 and 11 press the primary ring against the mating
ring. They ensure that the seal faces stay in contact with each other also during
unpressurised operation. The O-rings 12 and 18 provide sealing between the primary
rings / mating rings and the housing parts. The O-rings 17, 16 and 10 provide sealing
between the seal cartridge and the pump casing. The O-ring 19 provides sealing
between the cartridge and the shaft. The O-ring 13 provides sealing between the
mating ring carrier 6 and the shaft sleeve 1. Torque transmission from the shaft to
the shaft sleeve is effected by the key. The parallel pins 2 and 14 as well as the thrust
rings 5 and 9 ensure transmission of the torque from the primary rings and mating
rings to the housing parts.
To prevent dry running of the outboard seal, the pressure of the buffer fluid applied
to the seal must equal the ambient pressure as a minimum. The space between the
inboard seal and the outboard seal must be completely filled with this fluid and
vented.
Summary of Contents for 4STQ Series
Page 1: ...KSB Mechanical Seal 4STQ Installation Operating Manual...
Page 43: ......
