3
1 GENERAL
1.1 Scope of the manual
This installation, operation and maintenance manual provides
essential information on trunnion mounted XG/XM series ball valves.
The actuators and instrumentation to be used with these valves are
also discussed briefly. Refer to the separate actuator and control
equipment instruction manuals for further information.
1.2 Valve description
Trunnion mounted XG/XM series valves are flanged full bore ball
valves. The valve body is in two parts, fastened together by body-
joint bolting. The ball and shaft are separate. Shaft blow-out is
prevented by bonnet and a shoulder machined on the shaft.
The valve is either soft or metal seated. Shaft torque is transmitted to
the ball through a splined bore in the ball.
The valve is 1-way or 2-way tight depending on the seat construction.
Tightness direction is shown with an arrow on 1-way valves.
Construction details of individual valves are included in the type code
shown on the valve identification plate. To interpret the type code,
please refer to the type coding key in this manual.
Trunnion mounted XG/XM series ball valves are specially designed
for demanding throttling and shut-off service with high pressure
differentials.
1.3 Markings
Body markings are cast or stamped on the body (see Fig. 2).
The identification plate (Fig. 3) is attached to the flange.
Identification plate markings are:
1.
Body material
2.
Shaft material
3.
Trim material
4.
Seat material
5.
Max and min operating temperature
6.
Max shut-off pressure differential / temperature
7.
Pressure class
8.
Type designation
9.
Valve manufacturing parts list no.
10.
Model
NOTE:
Selection and use of the valve in a specific application requires
close consideration of detailed aspects. E.g. Q2G-trim is for
relatively clean gas applications, note possibility of clogging. Due
to the nature of the product, this manual cannot cover all the
individual situations that may occur when installing, using or
servicing the valve.
If you are uncertain about use of the valve or its suitability for your
intended purpose, please contact Neles for more information.
For valves in oxygen service, please see also the separate
installation, maintenance and operating instructions for oxygen
service (see Neles document id:10O270EN.pdf)
Fig. 1
Construction of a trunnion mounted XG/XM series ball
valve
Fig. 2
Valve markings
Fig. 3
Example of identification plate
Batch no
Nominal size
pressure rating
ID plate
Manufacturer’s
Body material
Body
material
mark
(1) (2)
(5)
(7)
(8)
(3) (4)
(6)
(9)
(10)
