Introduction; General; Principle Of Operation - GE Baker Hughes Masoneilan 31000 Series Instruction Manual

1. Introduction

The following instructions are designed to assist maintenance
personnel in performing most of the maintenance required
on the 31000 Series valve and, if followed carefully will reduce
maintenance time.
Spare Parts
When performing maintenance always use Masoneilan
replacement parts. Parts are obtainable through your local
BHGE Representative or sales office. When ordering parts,
always include Model and Serial Numbers shown on serial plate.
The use of the assembly tools is recommended to simplify
disassembly and reassembly work. These are listed in Figures
2 and 3 and can be obtained from BHGE Masoneilan parts
department.
Service
BHGE has highly skilled service technicians available to assist
you in the operation, start-up, maintenance and repair of our
valves and component parts. Contact your nearest BHGE
Representative or sales office.
Training
BHGE regularly holds training programs to train customer
service and instrumentation personnel in the operation,
maintenance and application of our control valves and
instruments. To participate in one of these training sessions
contact your local BHGE Representative.
Numbering System
1st 2nd
Actuator Type
35 Spring-opposed
rolling-diaphragm
Note: Actuator positions 1 and 2 are standard configurations.
View seen from actuator end. Other positions are available:
consult BHGE.
© 2017 Baker Hughes, a GE company. All rights reserved.
—
1st
3
Body
Series
—
31

2. General

The statements and information given in these operating
instructions apply to all sizes in the 31000 Series control valves.
The model number, size and rating of the valve are shown on
the serial plate. Refer to numbering system hereafter to identify
the valve model.

3. Principle of Operation

The concept of the 31000 Series is based on the proven rotating
plug principle:
• The valve plug, which forms one unit with the valve shaft, can
rotate eccentrically in a free flow design, flanged valve body.
The seating surface of the plug has the shape of a segment of
a sphere.
• The midpoint of the spherical seating surface lies eccentrically
to the axis of the shaft so that there is no contact between
seat and plug even when the valve is only partially opened.
Wear is reduced to a minimum.
• Excellent sealing in the seat/plug closure is achieved by the use
of PTFE and PFA, provided as a standard feature on the 31000
Series. The seat is fixed in the valve body through its conical
outside shape. The plug shaft is connected to the actuator
with the help of a lever. The actuator is operated by means of a
rolling diaphragm with opposing spring.
2nd 3rd
1
Actuator Mounting
(Type 35 Only)
1 Parallel to pipeline, air to close
2 Parallel to pipeline, air to open
4th 5th
0
Seat
Not Assigned
Material
1 PTFE
2 Special
Masoneilan 31000 Series Control Valve Instruction Manual | 2
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