Elkhart Brass ELKHART 294-11-CWB - Manual (Page 4)

II. Installation Instructions
1. How to Determine Nozzle Reaction Force
It is important to note that the piping must be able to withstand a horizontal force of at least
1-1/2 times the nozzle reaction force at the height of the vertical swivel joint center and
from any angle of rotation that the monitor is capable of turning.
The nozzle reaction formula for smooth bore nozzles is NR = 1.5 x d
2 x NP
The nozzle reaction formula for combination fog nozzles is NR = 0.0505 x Q x √P
Where NR = Nozzle Reaction (in pounds)
d
= Nozzle Discharge Diameter (inches)
NP = Nozzle Pitot Pressure (psi)
Q
= Flow (in GPM)
P = Nozzle Pressure (in PSI at nozzle inlet)
1.5 and 0.0505 are constants
An example of a 1-7/8” smooth bore nozzle flowing with a Pitot measuring 95 psi will have a
reaction force of 501 lbs.
The combination fog nozzle formula is with the nozzle set on straight stream. Reaction will
decrease as the stream pattern is widened to fog. For example, a combination fog nozzle
discharging 1000 GPM @ 100 PSI in a straight stream will have a reaction force of 505 lbs.
Maximum nozzle reaction force is 505 lbs.
Maximum monitor inlet pressure is 200 psi.
2. Monitor with NPT Base
Apply an appropriate thread sealant to the NPT nipple on the water supply pipe. Thread the
monitor base onto the nipple.
3. Monitor with Flat Faced Flange
a) Attach an ANSI pattern flat face companion flange to the water supply pipe.
b) Seal the flange joint with a full face gasket or suitable flange sealant.
c) Attach the monitor inlet flange to the companion flange on the water supply pipe with grade
5 carbon steel or stainless steel bolts with nuts. A 4.0” 150# ANSI flange requires eight
5/8” – 11 UNC bolts, minimum 2 ½” long.
d) Apply Loctite® #242 to the bolt threads, then thread on the nuts, and torque the flange bolts
to 60-70 ft-lbs uniformly increments of approximately 20 ft-lbs.
Warning:
When installing monitor on a raised face companion flange, it is critical that bolts be
tightened uniformly to prevent cocking of the monitor relative to the flange. If the monitor becomes cocked,
(see Figure 1) the monitor cast flange base will fracture and fail when the bolts on the "high" side are
tightened.