SPP id: Version 14 > / 150201 / Replaces 140901 / en /
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Series
2.15
INSTRUCTIONS
February 2015
Page
ISO
G
COPYRIGHT © SULZER PUMPS FINLAND OY
ORIGINAL INSTRUCTION
USER'S MANUAL – AHLSTAR
Safety instructions
Table 14,
Permitted misalignments on sealing surfaces
Nominal size of connection
Permitted misalignment on sealing surfaces (a)
≤
DN 150
0,2 mm
> DN 150
0,4 mm
2 The use of washers is recommended. When the screw is
≤
M24, one washer is used, and when the screw is
>M24, two washers are used.
3 Check the cleanliness of the sealing surfaces before installation. If necessary, clean the sealing surfaces
with a soft brush in the direction of the circumference, not in the direction of the radius.
4 The use of different material groups (carbon steel - stainless) in the flanges and screws may lead to a
harmful change in the internal forces of the connection as the temperature changes, and is therefore
prohibited.
5 The screws must be tightened using a torque wrench which is calibrated every two years in accordance with
ISO 6789.
6 The tightening must be performed in four stages. Follow the order given in Fig. 2 and first tighten 30% of the
final torque. After this, follow the same order and tighten 60% of the final torque. In the third stage, tighten
the screws to the final torque in the same order. Finally, secure the torque by tightening the screws
clockwise using the final value. The permissible torques depend on the flange standard used. The
permissible torques can be found in tables 15 to 16.
Fig. 2
The tightening torques must be checked within 24 hours from commissioning.
7 The following maximum torques have been calculated assuming that the friction coefficient is 0.2. The effect
of the friction coefficient must be taken into account by using the ratio given under item 1.
C A U T I O N
Exceeding the maximum torques can lead to permanent deformations in the flanges.