Fluid Components Intl ST51A, Installation, Operation & Maintenance Instruction Manual

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ST51A/ST75A/ST75AV Mass Flow Meters INSTALLATION
Fluid Components International LLC 9
Retractable Packing Gland Mounting
A retractable packing gland, with ½" MNPT or ¾" MNPT threads and graphite or Teflon packing, is a process connection option. FCI single
point flow meters are calibrated at the centerline of the process pipe. The flow element is properly mounted when the tip of the flow
element is located .50 inches (13 mm) past the pipe centerline. Follow the below steps to install/retract instruments with the retractable
packing gland option.
1. The scale etched on the side of the insertion probe indicates the length to the tip of the flow element. Calculate the Insertion depth
using the equation and Figure 6 below.
I = Insertion depth
I.D. = Pipe inside diameter
T = Pipe wall thickness
C = Pipe mounting coupling and compression fitting (installed length)
𝐼 = 0.50" +
𝐼.𝐷.
2
+ 𝑇 + 𝐶
I = __________
Figure 6 – Flow Element Installation, Retractable Packing Gland ST51A
2. Mark the insertion pipe at the calculated insertion depth.
3. Ball Valve Applications Only: If a ball valve is required, install the ball valve to the process mounting coupling. Close the ball valve
to prevent the process media from leaking out when installing the packing gland with the process line pressurized.
4. Apply the proper thread sealant compatible with the process media to the male threads of the packing gland. Fully retract the insertion
probe into the cavity of the packing gland and install the packing gland into the process mounting coupling or ball valve. If a ball valve
is not used, make sure to first depressurize the process line before installing.
5. Tighten the packing nut until the internal packing is tight enough to prevent excess process leakage, but also allow the insertion probe
to be inserted into place. For ball valve applications, open the ball valve after the packing nut has been tightened.
Caution: For applications where the process media is pressurized to greater than 232 psig [16 bar(g)] make sure to first
depressurize the process line before making the insertion.
6. Align the orientation flat and flow arrow parallel to the flow direction and proceed to insert the flow element into the process media
pipe up to the insertion depth mark.
7. Tighten the packing nut another ½ to 1 turn tight (approximately 20 ft-lbs) until the packing has created a full seal.
8. Ensure the locking collar is properly secured to the back of the packing gland. Torque the two No. 8-32 socket head cap screws on
the locking collar to 20 in-lbs using a 9/64" hex key.
C01444-1-1
CL
LOCKING COLLAR
PACKING NUT
MARK
INSERTION
DEPTH
OPTIONAL BALL VALVE:
CUSTOMER-SUPPLIED OR
PURCHASED FROM FCI