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131 Parker Hannifin Corporation
Parflex Division
Ravenna, Ohio
Coiled Air Hose,
Fittings
& Accessories
Hydraulic &PneumaticHose & Fit.
PTFEHose &Fittings
The
rmoplasticTu
bing
Truck (Fleet)
Products
Tooling &Equipment
Hose
Accessories
Technical &
Design
Information
Approvals &
Guides
Alphanumeric
Index
How To Select A Hose (STAMPED)
Size The appropriate inside and outside diameters and length of
the hose should be determined
Temperature The maximum temperature of the material being conveyed
Application External conditions including abrasion, climate, heat, flexing,
internal vacuum, and degrees of bending
Media The composition of the substance being conveyed and
chemical compatibility with the hose inner core, and if
applicable, outer jacket
Pressure The maximum pressure of the system, including pressure spikes
Ends The appropriate end connection and attachment method for the ap-
plication
Delivery Testing, quality, packaging, and delivery requirements
NOTE: Static dissipation and PTFE hoses
In the case of a PTFE hose, static electricity is caused when a non-conducting fluid flows
at a high velocity through the PTFE natural core tube. When a static charge builds up in the
tube of a PTFE hose, it will look for the path of least resistance to ground. If the tube is non-
conductive, then the path of least resistance may be to pierce through the wall of the PTFE
tube to the conductive stainless steel braid and eventually to the metal fittings and back to
ground through the equipment to which the hose assembly is connected.
The purpose of a static dissipating tube on the inside of the hose is to provide an acceptable
path of less resistance and allow the static buildup to dissipate through the core tube to the
metal fittings and eventually to ground. Parflex static-dissipating hose is designated with
a B after the series number. Example: Hose type 919B-6 is the static-dissipative version of
hose type 919-6.
PTFE Hose Tutorial & Introduction