Installation Of Primary Element For Welding-Ln; Installation Position And Piping; Primary Element With Possibility Of Direct Connection Of The Transmitter - Siemens SITRANS FP 7ME17.8 Operating Instructions Manual

Installing/connecting
Flange Removal
The device is delivered with measuring flanges. The device may have to be disassembled for welding in the flange
due to danger of improper heating. Welding in and inspecting the flange weld must be performed according to the
state-of-the-art and under adherence of the applicable welding provisions (for example AD 2000). The removal
flanges must correspond to DIN 19214 or ANSI B 16.36.
D-D/2-Tapping
According to ISO 5167, the following conditions must be met for D-D/2-tapping:
Distance between orifice plate and "+"-tapping: 0.9 D ... 1.1 D
•
Distance between orifice plate and "-"-tapping:
•
0.48 D ... 0.52 D for ß < 0.6
o
0.49 D ... 0.51 D for ß > 0.6
o
Both distances are measured from the front of the orifice plate (the plus side). The centre line of pressure tapping
must intersect the centre of the pipe axis under an angle of 90° if possible, but in any case it has to be within 3° to
the perpendicular line. The diameter of the pressure tapping bores must be less than 0.13 D and less than 13 mm.
5.5.4

Installation of primary element for welding-ln

Welding in and inspection of the weld of the primary element is, according to the state-of-the-art, under adherence
of the applicable welding provisions. Any required pressure tests must be performed after any required heat
treatment and inspection of the weld seams. The requirements from ISO 5167 to the pipes must be met (weld
seams, roughness, etc.).
5.6

Installation position and piping

5.6.1

Primary element with possibility of direct connection of the transmitter

The easiest and cheapest connection between the primary element and the transmitter is a primary element with
possibility of direct assembling. This assembling type is favored by standard orifices. In this case, a "sandwich" is
built by a 3- or 5-valve manifold and a transmitter which is fixed by 8 screws (4 on each side) under precondition
that the allowed temperatures on the diaphragm of the transmitter are not succeeded. The plus side of the
transmitter has to be connected with the plus side of the primary element. Both sealing surfaces (the one between
primary element and valve manifold as well as the one between the valve manifold and the transmitter) have to be
furnished one-sided with seal-rings inserted in the nuts. These seal-rings are part of the delivery. Therefore, an
installation of differential pressure pipes is not necessary.
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Operating Instructions, 08/2019, A5E46744245-AB
SITRANS FPS200