VEGA Mounting accessories, pressure measurement technology - Manual (Page 15)

6 Valve blocks
Valve blocks enable simple installation and setup of a differential
pressure transmitter.
The equalisation valve enables a pressure equalisation for the
measuring chambers when the process valves are closed. The zero
point of the pressure transmitter can be set with it.
The valves are opened (turning anticlockwise) or closed (turning
clockwise) via T-handles. The seal in the medium is purely metallic,
the seal of the valve spindles is a gland packing.
The valves blocks are available in the following versions:
l
3-fold valve block
l
3-fold valve block, flanging on both sides
l 5-fold valve block
The 5-fold valve block has two additional outlet valves for blowing out
the process lines or checking the differential pressure transmitter.
Rust, sand or similar pollution in the medium can build up around the
valve seat, especially when the system is flushed out before the first
setup. This can cause leakage around the valve seat. The spindle
must therefore be fully opened to permit flushing out.
When the prepressed packing is stored for a longer time, its sealing
ability can deteriorate. If necessary, the seal must be retightened at the
time of setup. The procedure is described in chapter "Maintenance
and fault rectification".
6 .1 3-fold valve block
The 3-fold valve block is used for standard applications. It has the
following functions:
l
Separation from the process
l
Pressure equalisation of the measuring chambers of the differ-
ential pressure transmitter
The mounting is carried out via integrated threaded connections and a
bracket existing on site.
Application area/Func-
tion
Handling
Series
Mounting and setup in-
structions
Storage
Application area/Func-
tion
Mounting
Mounting accessories, pressure measurement technology 15
6 Valve blocks
43478
-
EN
-121018