Hydraulics
Parker Hannifin Corporation
Quick Coupling Division
Minneapolis, MN
www.parker.com/quickcouplings
Hydraulic Quick Couplings
Double Shut-Off and Straight-Thru Couplings
Parker hydraulic couplings have a wide variety of designs,
each tailored to a particular application or use. This catalog
is arranged according to those categories. In each section the
construction of a specific design will be detailed. However,
based on the valving of the coupling, hydraulic couplings
generally fall into one of two groups, either Double Shut-Off or
Straight-Thru.
Double Shut-Off couplings are used extensively when it is
important to minimize fluid loss upon disconnection. Both
halves of the coupler, the body and the nipple, contain shut-off
valves. These valves open automatically when the body and
nipple are connected, and close automatically when the two
halves are disconnected—keeping fluid loss to a minimum.
Parker Straight-Thru couplings have no valves in either half
and are ideal for maximum flow application. Their smooth, open
bore offers the lowest pressure drop of any quick disconnect
coupling, and allows them to be thoroughly cleaned. Since there
are no valves in either half, fluid flow should be shut off before
the coupling is disconnected.
Rated Pressure
Rated pressure for the Parker hydraulic couplings range from
30
to 15,000 psi, depending on the coupling series, size and
materials. Rated pressures as shown in this catalog are
defined by ISO 5598, as “the qualified operating pressures
which are recommended for a component or a system by
the manufacturer.” Parker “Rated Pressures” have been
established on the basis of laboratory tests which include,
but are not limited to, static burst tests and multiple cycle
impulse tests. System characteristics such as high cycling
rates and high amplitude shocks either hydraulic or
mechanical, can reduce the functioning life of a coupling,
even if the system’s nominal pressure falls within the rated
pressure range of the coupling.
For assistance in analyzing your application, contact your
nearest Parker sales office or the Quick Coupling Division
in Minneapolis.
Refer to the Safety Guide at the end of this catalog for
considerations when selecting a Quick Coupling.
Refer to the Fluid Compatibility Chart (note Table of Contents)
for seal selection assistance for both Double Shut-Off and
Straight-Thru couplings.
Checklist for Selecting Quick Couplings
q
What are the functional requirements of the coupling?
q
What is the maximum working pressure of the application?
q
Which seals and body material are compatible with the system’s fluid?
q
Is the application static or dynamic?
q
What size coupler is required?
q
What is the maximum pressure drop suitable for the application?
q
Does the application require the ability to connect and disconnect under pressure?
q
What is the media temperature and ambient temperature?
q
What end configurations are required?
q
Is an industry interchange coupler required?
q
Is air inclusion and fluid loss a concern in the application?