The Company, L.L.C. Oklahoma City, Oklahoma Tel: (405) 672-6660 Fax: (405) 672-6661
wellmarkco.com
© The WellMark Company • Litho USA • All registered trademarks are the property of their respective owners. • IOM-2600SRV 110420 1
WellMark Series 2600 relief valves are certified for
gaseous application only and are not intended for
liquid service. Over-pressure of this relief valve or
installation of the relief valve in applications which may
see pressure levels beyond those for which the valve is
designed may result in leakage and/or catastrophic
failure. This failure could result in leaking gas/liquid,
damage to surrounding equipment, personal injury or
death. To prevent such damage/injury the valve should
be installed in a safe location and should be chosen
based upon the user’s specific application. These
valves are designed for relief to atmosphere only, and
are not intended for use in a closed system.
WARNING!
WARNING!
2600
Series
Installation & Maintenance Instructions
for Series 2600 Safety Relief Valve
INSTALLATION
WellMark safety relief valves should always be installed on a
vessel or pipeline in the vertical position with the outlet pointing
in a horizontal direction. It is recommended that the system
which is being fitted with a safety relief valve be cleaned prior to
installation, as construction materials, welding slag and/or
Teflon tape are items that commonly cause seating problems.
Relief valves should be installed using the guidelines
published by the ASME Section VIII of the Boiler and Pressure
Vessel Code, paragraph UG-135:
(a) Safety, safely relief and pilot operated pressure relief
valves, and non-reclosing pressure relief devices shall be
connected to the vessel in the vapor space above any
contained liquid or to piping connected to the vapor space in
the vessel which is to be protected.
(b) The opening through all pipe and fittings between a
pressure vessel and its pressure relieving device shall have at
least the area of the pressure relieving device inlet, and the
flow characteristics of this upstream system shall be such that
the pressure drop will not reduce the relieving capacity below
that required or adversely affect the proper operation of the
pressure relieving device. The opening in the vessel wall shall
be designed to provide direct and unobstructed flow between
the vessel and its pressure relieving device. (See Appendix M.)
(c) When two or more required pressure relieving devices are
placed on one connection, the inlet internal cross-sectional
area of this connection shall be either sized to avoid
restriction flow to the pressure relief devices or made at least
equal to the combined inlet areas of the safety devices
connected to it. The flow characteristic of the upstream
system shall satisfy the requirements of (b) above. (See
Appendix M.)
(d) Liquid relief valves shall be connected below the normal
liquid level.
(e) There shall be no intervening stop valves between the
vessel and its protective device or devices, or between the
protective device or devices and the point of discharge,
except:
1. when these stop valves are so constructed or positively
controlled that the closing of the maximum number of block
valves possible at one time will not reduce the pressure relieving
capacity provided by the unaffected relieving devices below the
required relieving capacity; or
2. under conditions set forth in Appendix M.
(f) The safety devices on all vessels shall be so installed that
their proper functioning will not be hindered by the nature of
the vessel's contents.
(g) Discharge lines from pressure relieving safety devices
shall be designed to facilitate drainage or shall be fitted with
drains to prevent liquid from lodging in the discharge side of
the safety device, and such line shall lead to a safe place of
discharge. The size of the discharge lines shall be such that
any pressure that may exist or develop will not reduce the
relieving capacity of the relieving devices below that required
to properly protect the vessel. [See UG-136 (a)(8) and
Appendix M.]
INLET
OUTLET
Any relief valve affixed to a vessel or pipeline should be done
so as to minimize the amount of piping between the vessel or
pipeline and the relief valve. Furthermore, any piping used
must be equal to or larger than the inlet pipe size of the relief
valve. Any reduction could cause serious problems in the
performance of the valve as it is intended, resulting in a
catastrophic disaster.
Outlet piping from the relief valve should never be more than
four feet in length. Pipe used is never to be of a size smaller
than the outlet size. Doing so may result in a reduction of the
valves designed flow capacity, resulting in serious danger to
life and equipment.
If outlet piping is installed outdoors care must be
taken to assure that liquids, if present, cannot form
an ice blockage in the piping or valve body. Ice
blockage can inhibit the valves ability to perform
properly and may result in serious damage or injury.
Discharge lines must have protective caps or drains
to prevent any liquid from collecting in the valve
body or outlet piping. Care should be exercised to
assure that any caps used do not cause any kind of
back pressure on the relief valve.
