Parker Hannifin Corporation
Quick Coupling Division
Minneapolis, MN 55427
46
Quick Coupling Products
Glossary of Terms
Air Inclusion
The ambient atmosphere forced into the system during the
connection of the quick disconnect halves.
Break-Away
Automatic disconnection of a coupling when an axial separation
force is applied.
Brinelling
Dimples or grooves worn into the shoulder of a male half by the
locking balls in the female half.
Burst Pressure
The pressure at which a device loses the capability to retain
pressure.
Case Hardening
Hardening the surface of low carbon steel..
Cold Flow
Continued deformation under load.
Connect Under Pressure
Ability to connect coupling halves with internal line pressure
applied to either both sides or one side.
Coupling, Female Half
Other nomenclature “coupler”, “socket”, “body”.
Coupling, Male Half
Other nomenclature “nipple”, “plug”, “adapter”.
Coupling, Quick Disconnect
A component which can quickly join or separate a fluid line
without the use of tools or special devices.
Differential Pressure(
P)
The difference in pressure between any two points of a system
or a component.
Double-Acting Sleeve.
Permits push-to-connect and pull-to-disconnect convenience on
implement line when female half is clamp mounted and
connected with a hose.
Dust Cap
Dust or dirt repelling enclosure for both halves.
Dust Plug
Dust or dirt repelling enclosure both halves.
Flow Checking.
Occurs when a nipple valve closes during flow conditions, such
as when quickly lowering a heavy implement. (Also called
Check Off, Back Checking or Lock-up.)
Flush Position (Valve)
When the coupler valve is fully open, allowing maximum oil flow.
Force to Connect
Axial and/or rotational force required to make a complete
connection.
Force to Disconnect
The reverse of the above.
Induction Hardening.
Localized hardening of medium carbon steel.
Peak Pressure
Maximum momentary pressure encountered in the operation of
a component.
Pressure Cap
Cap which incorporates a seal capable of withstanding the
rated pressures on the male half.
Pressure ImpulseTest
Subjecting a component to a specified pressure at a specified
rate of increase or decrease for a specified time limit.
Pressure Operating
The pressure at which a system is operated.
Pressure Plug
Plug which incorporates a seal capable of withstanding the
rated pressures on the female half.
Proof Pressure
The non-destructive test pressure in excess of the maximum
rated operating pressure.
PushTo Connect (Auto Lock)
Locking arrangement which permits one handed connection by
pushing the nipple into the coupler.
Rated Pressure
The maximum pressure at which a product is designed to
operate.
Single-Acting Sleeve
Permits pull-to-disconnect convenience on implement line when
female body is clamp mounted. Making connection requires
manually pulling female body forward, inserting male tip, then
allowing body and tip to return to original position in the clamp.
Sleeve Lock
Arrangement which provides an additional lock which must be
actuated before the locking sleeve can be retracted.
Spillage
The fluid removed from the system due to disconnection of a
coupling assembly. This is the fluid trapped between the mating
seal and the valve seal of the coupling halves.
Surge Pressure
The pressure existing from surge conditions.
Surge Flows
A rapid increase in fluid flow.
Thermal Build-Up.
Hydraulic pressure caused by expansion of the fluid due to heat
from an external source such as sunlight.
Trapped Pressure
Pressurized hydraulic fluid trapped behind closed coupling valve
Twist Lock
A locking arrangement which requires a rotational actuation to
unlock the mating halves.
Types of Quick Disconnect CouplingValves
Straight-Thru (ST)
This provides straight through flow.
Double Shut-off Valve (DSO)
A valve in the female half and a valve in the male half.
Single Shut-off Valve (SSO)
Generally, a valve in the female half with no valve in the male
half.