Masoneilan * 4700/48000 pages
GE Oil & Gas
nnnnMasoneilan* 4700/4800 fn/H- rhont
nnnnCorrosion Resistance Positioners TO CI S11661
nnnnMasoneilan models 4700E/4800E (electropneumatic) and
nnnn4700P/4800P (pneumatic) are field-proven positioners from
nnnnGE Oil & Gas that use a precision feedback cam to provide
nnnnaccurate positioning, fast response, and customized control
nnnncharacteristics for control valves. These positioners can
nnnnbe used with either rotary or reciprocating actuators. On
nnnnrotary actuators, the cam is mounted directly on the shaft.
nnnnWhen mounted on reciprocating actuators, a simple, rugged
nnnnturnbuckle and lever assembly couples stem motion to the cam.
nnnnThe main features of the models 4700P/4700E and 4800P/4800E
nnnnpositioners are:
nnnnOne Multi-lobe Cam
nnnnThe cam provides field-changeable linear, split-range linear and
nnnnequal percentage control characteristics. Custom characteristics
nnnnare available on special order.
nnnnZero Adjustment
nnnnAdjustment of the positioner zero can easily be accomplished by means
nnnnof the adjustable spring button. Further zeroing can be performed
nnnnthrough the turnbuckle assembly on linear motion actuators.
nnnnCorrosion-resistant Materials
nnnnPremium performance is the standard on the models
nnnn4700P/4700E and 4800P/4800E positioners. Internal
nnnncomponents are manufactured of corrosion-resistant materials
nnnnfor protection against the harshest environments.
nnnnFully Enclosed
nnnnAll adjustments are fully enclosed for protection from the
nnnnenvironment.
nnnnSimplicity
nnnnPositioner action can be reversed without additional parts
nnnn(4700P/4800P only). The same mounting orientation is used for
nnnnboth direct and reverse action.
nnnnEasy to Maintain
nnnnThe pilot valve is the only moving part in the pilot housing. It
nnnnis easily removed without disassembling any other part of the
nnnnpositioner. An optional bypass valve module is available for use
nnnnon the model 4700P pneumatic direct acting positioner. Where
nnnnoperating parameters allow, it permits the positioner to be
nnnnisolated for maintenance while operating the valve directly with
nnnnthe instrument signal. The bypass module is mounted on the
nnnnback of the positioner to discourage tampering.
nnnnOptional Bypass
nnnnA molded nylon bypass valve with an O-ring seal permits
nnnncontinued automatic control during the cleaning of the pilot
nnnnvalve. The bypass valve is concealed in back of the unit to
nnnnprevent tampering. The bypass is available only on the direct
nnnnaction 4700P pneumatic positioner.
nnnnDamping Adjustment
nnnnOn model 4700, actuator travel speed can be adjusted as
nnnnrequired for stable operation
nnnnimagination at work
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