PORT DESCRIPTIONS
Dynex pumps are available with outlet ports suitable
for use at various pressure ranges. Contact the fitting
manufacturer to ensure the selected fittings are rated for
the maximum pump operating pressure.
S.A.E. Straight Thread Ports
The Straight Thread connection (S.A.E. J1926/1) is
sometimes referred to as an S.A.E. o-ring boss, or ORB.
The port consists of a machined spotface surface, a
tapered seal cavity and a straight thread port.
The fitting forms a seal by compressing the o-ring in the
seal cavity with the underside of the flanged wrench flat.
Some adjustable fittings, such as elbows and tees, use a
locknut with a captive backup washer for compression.
S.A.E. Straight Thread ports are not recommended for
operation above 8000 psi (560 bar). Also, the maximum
pressure of pumps with No. 12 S.A.E. outlet ports may
be limited by the pressure rating of the available fitting.
Contact the fitting manufacturer for ratings.
Coned and Threaded Ports
High-pressure pumps are available with coned and
threaded outlet ports, which use Autoclave Medium
Pressure, Butech M/P, or equivalent fittings.
These fittings provide a metal-to-metal seal with an
interference fit, not requiring an o-ring. The gland nut
holds the sleeve and tubing against the cone surface.
A weep hole, visible on the outside of the pump cover,
acts as an indicator of any abnormal leakage caused by
system conditions (i.e., excessive pressure). It allows
any fluid which does leak past the sealing surfaces to
escape, preventing pressure build-up and possible damage.
7
PUMP
COVER
O-RING
COUPLING
Typical S.A.E. Straight Thread port connection
Typical British Standard Pipe (parallel fitting
with shoulder) port connection
PUMP
COVER
COUPLING
SEAL RING
SHOULDER
O-RING
PUMP
COVER
FLANGE
BOLTS
BOL
BOL
Typical S.A.E. 4-Bolt Flange port connection
WEEP
HOLE
GLAND NUT
TUBING
SLEEVE
PUMP
COVER
Typical Coned and Threaded port connection
British Standard Pipe Ports
High-pressure pumps are available with flat face ports
with British Standard Pipe (B.S.P.) parallel threads (BS
2779 or ISO 228), ideal for use on some European appli-
cations.
The fitting forms a seal by compressing a flat elastomer
ring on a machined spotface surface. There are several
sealing methods for these ports.
The recommended fitting has a recessed seal cavity
formed by a shoulder on the underside of the flanged
wrench flat (Voss “Peflex”, Form B Shoulder Seal; or
Parker Type E, “EOlastic” Seal; or equivalent).
B.S.P. ports are not recommended for operation above
10 000 psi (700 bar). Contact the fitting manufacturer,
to ensure the selected fittings are rated for the maximum
pump operating pressure.
S.A.E. 4-Bolt Flange Ports
Flange connections are often used for higher flows
requiring larger diameter tubing. The port consists of an
unthreaded port with four bolt holes in a rectangular pat-
tern on a machined face around the port (S.A.E. J518).
A typical fitting consists of a flanged head with a welded
tube and a captive flange with bolt holes. A seal is formed
by an o-ring in the groove on the underside mounting
surface of the flange head. As the flange bolts are alter-
nately tightened, the o-ring is compressed between the
flange head and the machined face on the pump.
To make mounting easier in tight spaces a two-piece
split-flange is often used.
