Consolidated 2478 Series Pressure Relief Valve Manual
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© 2020 Baker Hughes Company. All rights reserved.
•
Back Pressure
Back pressure is the static pressure existing at the
outlet of a safety valve device due to pressure in the
discharge system.
•
Blowdown
Blowdown is the difference between actual popping
pressure of a safety valve and actual reseating
pressure expressed as a percentage of set pressure,
or in pressure units.
•
Bore Area
Bore area is the minimum cross-sectional area of the
seat bushing.
•
Bore Diameter
Bore diameter is the minimum diameter of the seat
bushing.
•
Built-Up Back Pressure
Pressure existing at the outlet of a safety valve while it
is open and flowing through a discharge system.
•
Chatter
Chatter is abnormal, rapid reciprocating motion of the
moveable parts of a safety valve, in which the disc
contacts the seat.
•
Closing Pressure
Closing pressure is the value of decreasing inlet static
pressure at which the valve disc re-establishes contact
with the seat, or at which lift becomes zero.
•
Disc
A disc is the pressure containing moveable member of
a safety valve which affects closure.
•
Inlet Size
Inlet size is the nominal pipe size of the inlet of a
safety valve, unless otherwise designated.
•
Leak Test Pressure
Leak test pressure is the specified inlet static pressure
at which a quantitative seat leakage test is performed
in accordance with a standard procedure.
•
Lift
Lift is the actual travel of the disc away from closed
position when a valve is relieving.
•
Lifting Device
A lifting device is a device for manually opening a
safety valve, by the application of external force
to lessen the spring loading which holds the valve
closed.
•
Seat Bushing
A seat bushing is the pressure containing element
which constitutes the inlet flow passage and includes
the fixed portion of the seat closure.
•
Outlet Size
Outlet size is the nominal pipe size of the outlet
passage of a safety valve, unless otherwise
designated.
V. Valve Terminology
(Paraphrased from ASME’s PTC 25)
IV. Warranty Information
Warranty Statement:
Baker Hughes warrants that its
products and work will meet all applicable specifications
and other specific product and work requirements
(including those of performance), if any, and will be
free from defects in material and workmanship. Refer
to Baker Hughes’s Standard Terms of Sale, or specific
contract for complete details on warranty and limitation
of remedy and liability.
Defective and nonconforming items must be held
for Baker Hughes’s inspection and returned to the
manufacturer upon request.
Incorrect Selection or Misapplication of Products:
Baker Hughes cannot be responsible for customer’s
incorrect selection or misapplication of our products.
Unauthorized Repair Work
: Baker Hughes has not
authorized any non-Baker Hughes affiliated repair
companies, contractors or individuals to perform
warranty repair service on new products or field repaired
products of its manufacture. Therefore, customers
contracting such repair services from unauthorized
sources must do so at their own risk.
Unauthorized Removal of Seals
: All new valves and
valves repaired in the field by Baker Hughes Field
Service are sealed to assure the customer of our
guarantee against defective workmanship. Unauthorized
removal and/or breakage of this seal will negate our
warranty.
