Installation
Instructions
Experience In Motion
Dual Pressurized Seals
Dual RO, RO-TT, PTO, PT, RO-PTT,
BRO, BRT, MRO, MRT, and other
component seals
1 Equipment Check
1.1 Follow plant safety regulations prior to equipment disassembly:
1.1.1 Wear designated personal safety equipment
1.1.2 Isolate equipment and relieve any pressure in the system
1.1.3 Lock out equipment driver and valves
1.1.4 Consult plant Safety Data Sheet (SDS) files for hazardous material regulations
1.2 Disassemble equipment in accordance with the equipment manufacturer’s instructions
to allow access to seal installation area.
1.3 Remove existing sealing arrangement (mechanical seal or otherwise).
Clean seal chamber and shaft thoroughly.
1.4 Inspect surfaces under gaskets to ensure they are free from pits or scratches. Break all sharp
corners on shaft steps, threads, reliefs, shoulders, key ways, etc. over which gasket(s) must
pass and/or seal against.
1.5 Check shaft or sleeve OD, seal chamber bore, seal chamber depth, gland pilot, stud diameter,
stud bolt pattern and distance to first obstruction to ensure they are dimensionally the same
as shown in the seal assembly drawing.
1.6 Check seal assembly drawings for any modifications (reworks) to be made to the equipment
for mechanical seal installation and act accordingly.
1.7 The equipment must be earthed to prevent sparks due to static electricity discharge.
2
Shaft runout should be checked against the equipment manufacturer‘s specifications.
Generally, should not exceed 0.05 mm (0.002 inch) TIR (Total Indicator Reading)
at any point along the shaft for ball or roller type bearings.
For sleeve type bearings, refer to manufacturer instructions.
If the equipment is not completely dismantled, verify runout
near seal location.
The above values apply to shaft speeds in the range from
1000 to 3600 RPM. For values above and below, consult your
Flowserve representative. See Figure 1.
Shaft endplay should not exceed 0.25 mm (0.010 inch) TIR,
regardless of thrust bearing type. See Figure 2.
Radial bearing play at seal chamber face should be checked
against the equipment manufacturer’s specifications. Generally
0.05 - 0.10 mm (0.002 - 0.004 inch) will be applicable for ball o
r
roller type bearings. For sleeve or journal type bearings, values
will generally be in the order of 0.10 - 0.15 mm (0.004 - 0.006 inch).
If equipment is found outside the general range, contact the
equipment manufacturer and your Flowserve representative
to verify the equipment’s suitability for the seal.
Seal chamber squareness to the shaft centerline should
be within 0.0005 mm/mm (0.0005 inch/inch) of seal
chamber bore TIR.
Note: make sure that shaft endplay does not affect
the reading. Verify the smoothness of the seal
chamber face for a good gasket joint. See Figure 3.
Concentricity of the shaft to the seal chamber bore or gland
pilot register should be within 0.025 mm per 25 mm shaft
diameter (0.001 inch per 1 inch shaft diameter)
to a maximum of 0.125 mm (0.005 inch) TIR.
See Figure 4.
Figure 4
Figure 3
Figure 1
Figure 2
To first obstruction
Seal housing face to have a surface finish
of 1.6 μm (63 μinch) R
a
finish or better
Scribe
Mark A
Shaft or sleeve OD
+0.000 mm (+0.000 inch)
-0.050 mm (-0.002 inch)
+0.000 mm (+0.000 inch) API 610/682
-0.025 mm (-0.001 inch) DIN/ISO
Scribe
Mark B
Seal housing bore to have 3.2 μm
(125
μ
inch)
Ra finish or better
ANSI
Sleeve or shaft finish to be
0.8 μm (32 μinch) R
a
or better.
Gland pilot can be at either
of these register locations.
Surface finish requirements
Figure 5
3
Dual Seal Installation
2 Single End Suction Vertical Split Case and Vertical In-Line Pumps
(1 seal chamber)
2.1 Scribe Mark A on the shaft or sleeve at the face of the seal housing, Figure 5. Refer to the
assembly drawing provided with the seal for the seal setting dimensions. Scribe Mark B,
Figure 5, at this dimension from Scribe Mark A. (See Section 4 for ball drive designs).
2.2 Lubricate one of the two stationary face mounting O-rings or Duraflex rings with the silicone
lubricate provided with the seal and nest this O-ring in the gland cavity. Press the outer
stationary face into the gland with the sealing surface orientated toward the inboard side of
the gland. Use hand pressure only. Position the gland over the shaft or sleeve with the
stationary face sealing surface orientated toward the seal chamber (stuffing box). Place the
gland as close to the bearing bracket as possible. Do not bump the stationary face against the
shaft as it may chip, crack, or break.
2.2 Lubricate the shaft or sleeve with the silicone lubricant provided.
2.3 Install the rotating seal assembly on the shaft or sleeve:
• Outer rotating face with rotating face gasket O-ring, V-ring, or Duraflon wedge.
• Seal assembly.
• Inner rotating face with rotating face gasket O-ring, V-ring, or Duraflon wedge.
The rotating face sealing surfaces should be facing away from the springs and toward the
stationary faces. Be sure that the seal drive pins engage the drive slots in the rotating faces.
The RO, PTO, and similar designs have buttoned seal assemblies that can most easily be
installed on the shaft or sleeve as a unit with the rotating face gasket O-rings in place in the
bore of the rotating faces. The BRO, MRO, and similar designs are generally larger in diameter
and the rotating seal parts are most easily installed as individual components.
Handle Duraflon V-rings, wedge rings, Durafite, and Duraflex with extreme care. Duraflon
V-rings must be assembled individually and not pushed on the shaft or sleeve while they are
part of the rotating face or rotating seal assembly. Avoid nicking or pinching either lip of the
V-ring. Use both V-rings, they work together to form an effective seal.
Position the rotating seal assembly in its final axial position with the indicated position of the
seal drive lined up with Scribe Mark B. Tighten the seal drive set screws firmly and evenly.
2.4 Lubricate the seal chamber bore with the lubricant provided. The seal chamber is usually the
stuffing box contained in the pump back plate.
2.5 Lubricate the other stationary face gasket O-ring and place it on the back shoulder of the
inner stationary face. Slide the inner stationary face with the O-ring into position at the bottom
of the chamber. The rubbing or sealing surface of the inner stationary face should face out,
away from the impeller.
2.6 Wipe the seal faces clean with alcohol. Seal faces should not be lubricated but should be left
clean and dry.
2.7 Install the seal chamber (pump back-plate) and assemble the pump. Position the gland
to the face of the seal housing. Be sure the gland pilot is properly engaged. Tighten the gland
stud nuts evenly, cross stagger the adjustment of the nuts. Follow the equipment manufacturer's
recommendations for gland stud nut torque. In the absence of recommendations, gland nuts
should only be torqued to establish a leak tight seal at the gasket. Proper gland bolt adjustment
is especially important with a clamp style stationary face where excessive torque may damage
the face.
2.8 See Section 5, Operational Recommendations, before starting pump.
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