JETStream 3000 series - Rupture Discs; Bypass Valve; Regulator Valve (Not Shown); Discharge Fitting

Operation Manual
6
Rupture Discs
Two rupture discs are used in the system. The rup-
ture discs provide protection from excess pressure
in the system. If system pressure were to exceed the
rated pressure of the discs, the discs would burst.
If a disc bursts, water will ow through the ruptured
disc to provide relief for the system and protect
components from excess pressure. Check the discs
before operating the pump. Keep a supply of rupture
discs on hand for use. If a rupture disc should burst,
there is no way to build pressure until the disc is
replaced. Use only genuine Jetstream rupture discs
properly rated for the intended operating pressure.
Bypass Valve
The bypass valve controls the pump pressure by
bleeding off excess water and diffusing it to low pres-
sure. Turning the knob allows the operator to adjust
pressure during operation and relieve pressure when
not waterblasting.
The bypass valve controls pressure by allowing
water to bypass though the valve. A discharge hose
is attached to the bypass valve. The hose extends
to the other side of the unit where it is attached to a
drain elbow. Water that bypasses the valve will drain
from the bypass drain throughout operation.
The proper use of the bypass valve is to install the
correct size nozzle in the system so that the bypass
valve can be closed during operation. A combination
of plunger size, engine rpm, and nozzle will allow the
bypass valve to close at almost all ow rates.
Note: For pumps employing a shut in
system, a regulator valve is substituted
for a bypass valve.
Regulator Valve (Not Shown)
For shut-in systems (where no low pressure water
dumps from the gun), the bypass valve is replaced
with a regulator valve. The regulator maintains
constant system pressure when operating one or
more shut-in devices. When a gun or other device
is disengaged, the regulator automatically adjusts
to shift the excess ow to a low pressure outlet
while maintaining system pressure. Because shut-
in systems maintain constant system pressure, the
hydro-throttle does not function in these applications.
Discharge Fitting
The discharge tting allows the connection of a
high pressure hose. High pressure water exits from
this tting. On 15K manifolds, a quick disconnect is
recommended to prevent galling of pipe threads and
damage to the manifold.
Pressure Gauge
Hydro-Throttle
Switch
Water
Lubrication
System
Manifold Drain Valve
Manifold
Rupture Discs
Figure 2: Pump Components.