Samson EB 20b, Монтаж и эксплуатация

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3-7
EB 20b_EN
February 2022 edition
Subject to technical changes
Design and principle of operation
Ö
Fasten the body halves together with screws (10), washers
(12) and nuts (11) so they are hand-tight.
− Depending on the nominal size, stud bolts with nuts or screws
can be used.
− The fi nal screw connection of the body halves is performed dur-
ing a subsequent assembly step.
Ö
Clamp the ball valve in a vice for further assembly with the
base body
fl ange (1).
Damage to the fl ange due to improper handling!
Ö
Do not damage the housing fl ange, especially the sealing
surfaces.
Ö
Place the spring washer(s) (16) on the bushing (15). The lo-
cation and quantity of the spring washer(s) can be found on
the drawing, see Figure 3-2.
Ö
Place the centring ring (18) on the spring washer(s) (16).
Ö
Insert the set of spring washers (8) in the centring ring until
reaching the bottom ring of the V-ring packing. The arrange-
ment and quantity of the spring washers can be found on the
drawing, see Figure 3-2.
Ö
Insert the bearing bushing (7) into the stuf fi ng box fl ange (6).
Ö
Place the pre-assembled stuf fi ng box fl ange on the body and
adjust with screws (9).
Ö
Tighten the screws evenly in a criss-cross pattern until a gap
between 1 - 2 mm has formed between the stuf
fi ng box
fl ange and the body.
The fi nal screw connection of the stuf fi ng box is performed dur-
ing a subsequent assembly step
Ö
Tighten the screws (10) and nuts (11) on the body halves (1
and 2).
For the tightening sequence and tightening torques of the respec-
tive nominal sizes, see Figure 15.1 and Table 15.1 in Chapter
“15.1.1 Tightening torques”.
Ö
To complete the assembly, tighten the screws (9) on the stuff-
ing box (6) evenly and in a criss-cross pattern.
Prior to the leak test, actuate the valve a few times so that the ball
can centre on the seal rings and provide an optimal seal.
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NOTE
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3.5.4 Assembly of the ANSI ball valve
3.5.4.1 Assembly of the body halves
Ö
Place both body halves (1 and 2) with the fl ange facing
downward on an even and clean work surface, so that the
inside of the ball valve is easy to reach.
Ö
Drive the pin (21) in the case of NPS6 and NPS8 into the
base body (1).
Ö
Insert the seal rings (4a and 4b) in the body halves (1 and 2).
The seal rings may not be installed without clearance. To achieve
the tightness of the ball valve, the seal rings must be installed in
their seat with suf
fi cient clearance. If this is not possible, please
contact PFEIFFER.
Ö
Place the V-ring packing (5) in the PTFE bushing (17). The ar-
rangement and quantity of the V-rings can be found on the
drawing, see Figure 3-3.
Ö
Push the bushing (15) carefully over the packing (7) and the
PTFE bushing (17).
When this packing unit is preassembled, the bottom ring of the
packing (7) protrudes past the bushing (15).
Preassembly of the ball valve with the one-part ball/switching
shaft
Ö
Place the ball (3) on the seal ring of a body half (1 or 2).
Ö
Place the preassembled packing unit with a slightly rotary
movement over the stem of the ball.
Ö
Insert the ball stem with the V-ring packing into the packing
space in the body.
Make sure that the ball (3) and V-ring packing (5) are clearly fi t-
ted in the body.
For further assembly, see Chapter “3.5.4.2 Final assembly of the
ball valve”.
Preassembly of the ball valve with the two-part ball/switching
shaft
Ö
Place the preassembled packing unit with a slightly rotary
movement over the switching shaft (20).
Ö
Insert the switching shaft with the V-ring packing into the
packing space of a body half (1 or 2).
Ö
Insert the ball (3) on the seal ring such that the slit in the ball
sits perfectly on the dihedron of the switching shaft (20).
Make sure that the ball (3) with switching shaft (20) and V-ring
packing (5) are clearly
fi tted in the body.
For further assembly, see Chapter “3.5.4.2 Final assembly of the
ball valve”.
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