ABB 266 HART Series, Operating Instruction

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2600T Series Pressure transmitters | OI/266/HART-EN Rev. D 23
Process connections considerations
266 differential pressure transmitter process connections on
the transmitter flange are 1/4 - 18 NPT, with a centers distance
of 54mm (2.13in) between the connections. The process
connections on the transmitter flange are on centers to allow
direct mounting to a three-valve or five-valve manifold.
Flange adapter unions with 1/2 - 14 NPT connections are
available as an option. Rotate one or both of the flange
adapters to attain connection centers of 51mm (2.01in), 54mm
(2.13in) or 57mm (2.24in).
To install adapters, perform the following procedure:
– Position the adapters with the O-ring in place.
– Bolt the adapters to the transmitter flange using the bolts
supplied.
Tighten the bolts to a torque value of 25Nm (stainless steel
bolts) or 15Nm (for Stainless steel NACE bolts).
– Deviations for models 266Mx, 266Rx and for PTFE O-rings:
pretightening hand-tight. Pretightening to 10 Nm. Final
tightening to 50 Nm.
– For model 266PS, 266VS and 266RS, it is only possible to
have one adapter, with low pressure side flange without
process connection and drain/vent valve.
– For high static model (266DSH.x.H) tighten the bolts to a
torque value of 40 Nm (regardless of the material of the bolts
used). In case of PTFE O-rings, pretightening to 10 Nm and
final tightening to 50 Nm.
Kynar inserts connection
When connecting Pressure transmitters equipped with kynar
inserts tighten the bolts to 15 Nm max.
Screw torques for models 266MS and 266RS with Kynar
inserts
The following procedures apply to process flange screws and
nuts:
Pretightening to 2 Nm (working crosswise).
Pretightening to 10 Nm (working crosswise) and then tightening
by a tightening angle of 180°, working in two stages of 90° for
each screw, and working crosswise.
Figure 25: Kynar insert
Figure 24: Flange adapter