Fisher 912 Series Instruction Manual

Fisher Controls
R
W ARNING
To avoid injury or equipment damage, these
regulators should be installed, operated, and
maintained in accordance with federal, state
and local codes, rules and regulations, and
Fisher instructions. Only a qualified person
must install or service a regulator. Be certain the
control spring range label is updated to accu-
rately indicate any field changes in equipment,
materials, service conditions, or pressure set-
tings.
Immediately call a qualified technician in case
of trouble. If venting occurs, or a leak develops
in the system, it indicates that service is re-
quired. Failure to correct the situation immedi-
ately may create a hazardous condition.

INTRODUCTION

Scope of Manual

This manual provides installation, maintenance, and parts
information for the 912 Series pressure regulators (figure 1)
as used in industrial/natural gas applications.

Description

The 912 Series pressure regulators are self-operated,
spring-loaded devices built to provide accurate, sensitive
control suited to a variety of applications.
As outlet pressure begins to exceed the set pressure, the
diaphragm inside the regulator lifts, operating a lever to
eFisher Controls International, Inc. 1979, 1991; All Rights Reserved
Instruction Manual
912 Series
Pressure Regulators
May 1991
W2217
Figure 1. Type 912 Regulator
close the inlet. Pressure in excess of the relief valve spring
force opens the relief valve, allowing excess pressure to
bleed through the screened vent in the spring case.

Specifications

Specifications for the 912 Series pressure regulators are
listed in table 1.
INST ALLA TION
W ARNING
Personal injury or equipment damage may re-
sult if the regulator is installed where service
conditions could exceed the pressure or tem-
perature specifications in table 1. The regulator
must not be used for hazardous gas service in
a closed area unless the vent is piped to a safe
912 Series
Form 5124