KSB MIL 41000 User manual

The following instructions should be thoroughly
reviewed and understood prior to installing, operating
or performing maintenance on this equipment.
Throughout the text, safety and/or caution notes will
appear and must be strictly adhered to, otherwise, serious injury
or equipment malfunction could result.
Instruction Manual
Purchase Order No : ___________________________________________
MIL 41000
Heavy Duty Cage Guided Control Valves

TABLE OF CONTENTS
Note: Easily replaceable Pressure gauges for Air sets and externally mounted Pressure gauges of
positioners are normally dismantled, separately packed and bound to the actuator yoke as a
precaution against transit damages. This may be noted while opening the boxes.
Warning: Do not lift large size valves by the actuator. Lifting lugs provided on the
actuators are for lifting the actuator alone.
1. Introduction............................................................................................................3
2. General....................................................................................................................3
3. Unpacking ...............................................................................................................4
4. Installation ..............................................................................................................4
5. Air Piping .................................................................................................................4
6. Valve Disassembly....................................................................................................4
6.1 Body Disassembly....................................................................................................4
6.2 Plug Disassembly.....................................................................................................6
7. Maintenance & Repair.............................................................................................6
7.1 Packing Box..............................................................................................................6
7.2 Repair Of Seating Area............................................................................................8
7.3 Stroke Change.........................................................................................................8
8. Body Reassembly.....................................................................................................8
8.1 Plug Stem Pinning...................................................................................................9
8.2 Plug & Cage Assembly..........................................................................................10
2

1. Introduction
Note: When specifying parts, always
include Serial Number of the valve.
Caution: Skilled service personnel to be
engaged for start up, maintenance and
repair of the valve.
Caution: Always use original MIL
replacement parts while performing
maintenance.
2. General
The following instructions should be thoroughly
reviewed and understood prior to installing,
operating or performing maintenance on this
equipment. Throughout the text, safety and/or
caution notes will appear and must be strictly
adhered to, otherwise, serious injury or
equipment malfunction could result.
MIL has a highly skilled Aftermarket
department available for start-up, maintenance
and repair of our valves and component parts.
Arrangements for availing their service can be
made through your local representative or
Aftermarket department. In addition, a
regularly scheduled training program is
conducted at our factory, to train your service
and instrumentation personnel in the operation
and maintenance. Also when performing
41000 series heavy duty cage guided control
valves are engineered for the most demanding
applications in the industry, ranging from
power generation to integrated petroleum and
chemical processing plant and a host of other
modern process industries. MIL 41000 series
valves are available with a wide range of sizes
from 1” to 32” and ratings from ANSI 150# to
2500#. Leakage class II,III, IV & class V (tight
shut off) are available. Refer Numbering system
Figure1 for valve nomenclature and choose
appropriate maintenance procedure.
The following instructions for installation and
maintenance are compiled to assist personnel in
Numbering System
Figure 1
Body Series Plug Type Trim
Characteristic Cage Type
41.Cage Guided
Globe
71.Cage Guided
Angle
0. Undefined
1. Unbalanced
Balanced Designs
2. With Static Seal Ring
3. With Pressure-energised
Polymeric Seal Ring
4. With Auxiliary Shut-off Pilot Plug
5. With Metallic Seal Ring
6. With Polymeric Seal Ring
7. High Capacity Unbalanced
9. With Graphite Seal Ring
0. Undefined
1. Linear
2. Equal %
3. Customised
X. On-Off
0. Undefined
1. Standard
2. Single Stage
Lo-dB / Anti-cav
3. Double Stage with
Diffuser Seat Ring
4. Double Cage
Lo-dB / Anti-cav
3
maintenance, please ensure that only MIL
replacement parts are used.
performing most of the maintenance required
on the MIL 41000 series control valves.
Recommended spare parts required for
maintenance are listed in Parts List of page 12.
The model number, size, rating and serial
number of valve are shown on the identification
tag located on the actuator. Special supplements
or addendums to this instruction manual may
be required for special engineered products
developed to meet specific customer
requirements.
For actuator and other valve accessories please
refer respective instruction manuals.
If maintenance is followed carefully it will
reduce maintenance time.

3. Unpacking
Warning: Care must be exercised when unpacking the valve to prevent damage to the
accessories and component parts. Should any problems arise, contact your local
representative or MIL Aftermarket department. Do not remove end protection cover
before installation.
4. Installation
Caution: Before installing the valve in the
line, clean piping and flush the line to
remove all foreign material such as
welding chips, scale, oil, grease or dirt.
End flange gasket surfaces must be
thoroughly cleaned to ensure leak proof
joints.
To allow for in-line inspection, maintenance and
removal of the valve without service
interruption, provide a manually operated stop
valve on each side of the control valve and a
manually operated throttling valve in the by-
pass line.
Figure 2
By Pass Line MOTV
Main Line MOSV CV MOSV
Warning: The valve must be installed
so that the fluid will flow through the
valve in the direction indicated by the
flow arrow located on the body.
Standard flow directions for MIL 41000 series
valves are as follows.However if the arrow
marked on the body indicates a different
direction, it may be a special design and the
same may be followed.
Flow to Open
Unbalanced design (41100, 41700), Balanced
with Self-energised Seal Ring design
(41200/41300), Balanced valves
(41500/41600/41900) in gas/steam service,
Single / Double Stage Low Noise valves (41002
/ 4) in gas service
Flow to Close
Auxiliary Shut-off Pilot Plug (41400), Balanced
Single Stage valves (41500/41600/41900) in
liquid service, Single Stage Anti-cavitation
valves (41002 ) & Anti-cav/Lo-dB valves with
diffuser (41003).
Caution: Where insulation of the valve
body is required do not insulate the
valve bonnet.
Note: Few useful installation
guidelines are illustrated in page 15.
5. Air Piping
Air piping shall be as per the specification of air
filter regulator. All connections must be free of
leaks
Warning: Do not use air supply
pressure greater than specified on tag
plate located on the yoke of actuator.
6. Valve Disassembly(figures 3-10)
The first step is to remove actuator, accessories
& pneumatic/electrical connections. Access to
the internal components of body should be
accomplished with the actuator removed. To
carry out this operation, refer instruction
manual for actuator.
Caution: New gaskets, packing & seal
ring (in case of balanced valves) should
be on hand before disassembling the
valve, since it is recommended that new
gasket, packing & seal ring are to be
used during reassembly.
Caution: Prior to performing
maintenance on the valve, isolate the
valve, vent the process pressure and shut
off air supply and signal air or electrical
lines to the unit.
6.1 Body Disassembly
A. Remove packing flange nuts (3) then
remove packing flange (4) and packing
follower (5).
4

Valve Plug
Guiding Surface
g
Seating Surface
Guiding Surface
Figure 4
Guiding
Surface
Cage
Seating Surface
Pilot
Guiding
Surface
B. Remove body stud nuts (10).
C. Separate bonnet (8) from body (18).
D. Ensure exposed part of stem (1) is clean
and free of dirt to enable it to slide
through the packing and to ensure
smoothness of stem surface when
removing the bonnet (8).
Note: It is suggested that two tapered
pieces of flat stock be inserted at the
o
bonnet-to-body joint, 180 apart to
simplify initial separation of the bonnet
from the body. Two heavy screwdrivers
o
placed 180 apart could also be utilized.
Pressure should be applied evenly to
prevent the bonnet from binding on the
stem or cage.
E. Push the plug stem (1) down so that the
plug is on the seat (16) and slowly remove
the bonnet (8) ensuring that the plug stem
(1), plug (14) and cage (15) remain in the
body (18).
F. Remove packing (7) packing spacer /
lantern ring (6) and guide bush (23) from
the bonnet (8).
G. Remove flat spring (19) (which is used for
valve sizes greater than 6" (150mm)) and
body gasket (11).
H. Remove plug (14) and cage (15) from body
(18) by pulling upward on the plug stem
(1). (41400, 41500, 41600 & 41900 series
valves). Then remove plug (14) from cage
(15) by lifting cage over top of plug stem.
l
l
In case of 411,412,413,417 series valves,
the plug is removed by pulling the plug
stem straight up. Remove the cage, by
pulling the same from the body. The
clamping cage (only for 41200) is then
removed and then the seal ring S/A (13)
can be removed. Please note that seal ring
is not applicable for 41100 & 41700
series.
In case of 41900 series valve [valve plug
equipped with a graphite seal ring (13)],
care should be taken when removing the
plug from the cage so that the seal ring is
not damaged.
I. Inspect seal ring (13) after disassembly
and replace if it shows signs of wear.
J. Lift out seat ring (16) and seat ring
gasket (17) from the body (18).
Warning: Care must be taken not to
damage the seating area and guiding
area of plug, seat ring and cage.
Caution: If a new seat ring gasket is
not available, care must be taken to
preserve the old gasket for re-use.
Spiral wound gaskets are standard in
this design and it is recommended that
a new gasket be installed each time
the valve is disassembled.
K Clean and inspect all components for
excessive wear or damage.
Note: Inspect all guiding, seating and
sealing surfaces (Figure-4). Metal
guiding and seating surfaces must be
free of scratches, dents, nicks, etc. Since
new gaskets are to be used during
reassembly, old gaskets should be
discarded. Replace all excessively worn
or damaged parts. After determining the
maintenance required, refer to the
appropriate section of this instruction
manual.
5

6.2 Plug Disassembly
A. Plug Stem Disassembly.
(Model 41100,41200,41300,41500,41600,41700
& 41900)
The valve plug stem (1) is screwed and pinned
into valve plug (14). To disassemble the stem,
hold the valve plug rigidly, taking care not to
damage the guiding surfaces. Disassemble the
plug stem pin (12) from assembly. By
means of flats or using a nut and counter-nut
on the end of the stem, unscrew the stem from
the plug taking care not to apply bending
moment which could deform it.
B. Auxiliary Pilot Plug Disassembly.
( Model 41400)
Figure 5
Pilot Plug Open
Pilot Plug Closed
Valve sizes 3" or 4" (80 or 100 mm)
Pressure must be applied on the pilot plug (21)
to compress the pilot spring (22). The retaining
ring (20) can now be removed, thus allowing
removal of the pilot and spring from the valve
plug.
Valve sizes 6" through 20" (150 through 500
mm)
Insert socket head cap screws through the holes
provided in pilot plug (21) engaging cap screw
in holes provided in the plug (14) (see number
and sizes of screw in table of Figure 6). Tighten
cap screws progressively until the retaining ring
(20) can be removed. Then, loosen cap screws
in same manner until the pilot (21) and spring
(20) can be removed.
If the pilot tip and (or) guide shows damage, the
pilot must be replaced. If pilot seat on the valve
plug shows signs of minor damage, it should be
turned on a lathe to remove the damaged areas.
However, not more than 0.010" (0.25 mm)
material should be removed in case of 3" or 4"
(80 or 100 mm) sizes. For sizes 6" through 20"
(150 through 500 mm), not more than 0.015
(0.4 mm) material should be removed. The seat
angles shown in Figure 11 must be followed.
Figure 6
7. Maintenance & Repair
The purpose of this section is to assist
maintenance personnel by suggesting methods
of component maintenance, which is largely
dependent on the tools and machine shop
equipment available.
Caution: If a valve needs frequent
maintenance, please consult MIL with
current operating parameters for
checking valve selection. Process
conditions should be stabilized and
determined accurately in case they were
not correctly anticipated when original
valve was specified.
Each section should be completely read and
understood before proceeding.
7.1. Packing-Box (Figures 7-10)
Packing box maintenance is one of the principle
actions in routine servicing. Tightness of the
packing is
maintained by packing compression.
Compression is achieved by evenly tightening
the packing flange nuts (3) against the packing
flange (4). Care must be taken not to over
tighten as this could prevent smooth operation
6

Caution: Valve must be isolated and
the pressure vented before performing
packing box maintenance.
Figure 9 Figure 10
Eco-lock packing
Figure 8
Standard Packing Spring Loaded Packing
Bonnet shall be dismantled from body and
actuator as mentioned earlier to perform
packing box
Proceed as follows:
A. Loosen and remove packing flange nuts
(3).
B. Raise packing flange (4), and packing
follower (5) up through the valve stem.
Note: They may be taped in place to
keep them out of the way before
proceeding.
C. By means of a hooked instrument,
remove packing (7) ensuring not to
damage the sealing surfaces of the
packing box or plug stem.
D. Replace packing set as supplied by MIL
Note: Assemble and compress rings
one at a time into packing box. If rings
are skive cut, the skive cut of each
packing ring must be placed about 120
degrees apart.
E. For Eco-lock type packing do not
change the sequence of packing
arrangement. The packing is available
as a set of inner packing and outer
packing. Use the packing as a set only.
Note: MIL Eco-lock packing (Figure 9)
is a high performance system to keep
fugitive emissions within allowable
limits. The packing is provided with
the inner packing and outer packing
as a set. It consists of 'V' and double
'V' packing rings with varying density,
which is designed to prevent fugitive
emission from the packing effectively.
Caution: For eco-lock packing, inner
and outer packing to be replaced as
a set only
F. Replace packing follower (5) and packing
flange (4).
G. Replace and tighten packing flange stud
(2) & nut (3).
Caution: Do not over tight packing
flange.
H. Place valve back in service and tighten
packing only as much as is necessary to
stop leaking.
Note: A spring loaded follower assembly is
used to maintain a constant load on the
packing, and is necessary for thermal cycling
applications. As the definition of thermal
cycling can vary, and processes are potentially
subject to unpredicted thermal gradients. Both
standard and eco-lock Systems are available
with the spring loaded follower (Figure 10).
7
of the valve. If all compression is used up and
the valve leaks, then new packing is required.
Caution: Packing box should be clean
and free of burrs, rust, and any
foreign matter. Parts can be cleaned
with denatured alcohol.

7.2 Repair of Seating Area
Any trim part which is scored or has damage on
guiding surfaces, to the extent that the same
could interfere with proper valve action, should
be replaced.
Minor scratches or nicks in seating surfaces of
either the plug or seat ring, should be repaired
in the following manner:
A. Lapping the Pilot Seat for 41400 Series
Valves (Auxiliary Pilot Plug Design)
After the pilot seat has been turned, it must be
ground as follows:
1. Apply a good grade of fine grinding
compound at several spots equally spaced
on the periphery of the seating surface of
the plug.
2. Place the pilot, with stem attached, in the
seated position without assembling the
pilot spring (22).
3. To facilitate lapping, screw a rod with T-
handle on top of the valve stem and secure
with a locknut. Or as an alternative, drill a
hole through a small flat
Figure 11
Models
Angle-A Angle-B
(Deg.) (Deg.)
piece of steel and fasten it to the plug stem with
two locknuts.
4. Lap by rotating the plug in short
oscillation strokes. After 8 or 10 strokes,
O
lift plug and turn 90 . Repeat the lapping
operation.
Note: Intermittent lifting is important
to keep the plug and seat concentric
during lapping. The lapping operation
should be repeated four times before
removing the pilot. If there is a dull
grey ring around the entire seat, the
lapping is complete. The grey area must
be as thin as possible. Do not lap to
cover the complete seat area width.
This will destroy the effectiveness of
the seat. If the ring is not continuous
repeat the entire lapping operation
until the ring is continuous. Remove all
the compound when the lapping
operation has been completed.
Reassemble the pilot in valve plug.
B. Lapping of Main Seat for 41100, 41200,
41300, 41400, 41500, 41600, 41700 &
41900 Series Valves.
If seating surfaces on the valve plug and seat
ring show signs of minor damage, they should
be turned on a lathe, to remove the damaged
areas. However, not more than 0.010" (0.25
mm) material should be removed in case 2", 3"
or 4" (50,80 or 100 mm) sizes. for sizes 6"
through 32" (150 through 800 mm), not more
than 0.015 (0.4 mm) material should be
removed. The seat angles shown in Figure 11
must be followed.
Lapping the main seat can be done in the same
manner as described above of pilot seat.
However the trim including the gaskets should
be assembled in the body. In case of sizes 6"
(150 mm) and above, the flat spring (19) should
also be assembled.
The bonnet, with the guide bush (23) in it
should be temporarily placed in position to act
as an alignment fixture for the lapping
operation. Four nuts spaced equally apart may
be tightened to keep the bonnet in position.
Caution: Do not tighten the nuts to the
required torque as the bonnet is being
used temporarily for guiding purpose.
7.3 Stroke Change
Stroke change is possible at site for an existing
41000 series valve equipped with MIL 37/38
spring diaphragm actuators.
This can be easily performed at site provided the
plug stem (1) is adaptable to the new stroke. If
the required stroke is less than existing valve
stroke, same can be
8

achieved using a new plug stem which is longer
by the difference between existing and required
stroke. On the other hand, if the required stroke
is more than existing valve stroke, same can be
achieved using a new plug stem which is shorter
by the difference between required and existing
8. Body Reassembly
After completing the required maintenance, the
valve should be re-assembled using the
following procedures.
8.1. Plug Stem Pinning
Plug stem pinning during field assembly may be
divided into two parts:
l
l
Replacing old plug and old stem.
Replacing only old stem.
Screwing Stem into Plug
A. Measure the depth of the thread recess in
the plug (X in Figure 12) and make a
reference mark to the plug stem at the
same distance, from the thread. In case
the plug stem has a shoulder with two
flats to improve the strength of the plug
and stem assembly and to facilitate
screwing and tightening, then this step is
not required.
B. If the plug is already fully drilled(typical
for 440C, solid satellite), then drill the
stem to same diameter (diameter C in
figure 12 )as the shank hole.
C. If the plug shank area has not any hole or
any center mark, measure the “D”
dimension, (see
Figure12). Place the plug shank on a V-block
and, by means of a center punch, make a
Plug Stem Pinning
Figure 13
center mark on the plug shank area.
Using a suitable size drill bit, drill the
plug-stem assembly.
D. Hold the plug in a vise. Apply a small
amount of grease compatible with the
fluid process on the threaded part of the
plug stem.
E. If the plug stem doesn't have a shoulder,
lock one nut against another one to the
end of the new plug stem and, using a
wrench on the upper nut, screw the stem
solidly into the plug. When properly
assembled, the reference mark should be
flush with the end of the plug shank.
F. Select the correct size pin according to
plug shank diameter and stem diameter,
(see Figure 12). Apply a small amount of
grease on it, and hand place the pin to
the hole inlet.
G. By means of a hammer, introduce the
pin into the hole. Complete the pinning
operation, taking care to ensure that the
pin is recessed by the same amount at
both sides (see Figure 12).
Note: Using a ball tooling and hammer,
caulk the pinhole edge of the plug.
(Except in case of plug in 440C St.,
hardened material or solid stellite).
9
stroke.
The new stem can be ordered on our Aftermarket
department. While ordering, do not forget to
mention existing valve serial no. and new stroke
required.
Valve plug stem
diameter
B
Plug shank
diameter
APin diameter
C
Pin lenght
F
Hole
location
D
Distence
XWrench size
E
Torque
T
Non-shouldered
stem
shouldered
stem
Ft.ibs Ft.ibs
In.
In.
In.
In.
In.
In.
In.
½
5/8
3/4
1.0
2
12.7
15.87
19.05
24.4
50.8
.79
.98
1.38
1.66
4
20
25.5
35
44.5
100
0.14
0.2
0.2
0.2
0.5
3.5
5.0
5.0
5.0
12.0
daN.m daN.m
mm.mm.
mm.
mm.
mm.
mm.
mm.
.70
.95
1.2
1.58
3.8
18
24
30
40
96
.91
1.1
1.77
1.88
3.8
23
28
45
47.5
96
.24
.30
.75
.98
2.0
6
8
19
25
50
11/16
7/8
11/76
11/4
2.3
17
22
27
30
60
37
118
118
118
5
16
16
16
44
118
118
184
250
6
16
16
25
34

H. After the plug has been pinned, it should
be placed in a lathe to insure it is
running “true.” The stem should be
placed in a collet with the plug shank
against it and the plug should be struck.
Alignment of plug stem can be
performed using appropriate means.
8.2. Plug & Cage Assembly
Caution: Ensure that any recommended
lubricant or sealing compound is
compatible with the process fluid. If
not, substitutes must be used.
A. Ensure that all the seating and guiding
surfaces are clean and free of any dirt,
scale or burrs.
B. Install the seat ring gasket (17) and seat
ring (16) into the body (8).
Plug & Cage Assembly for 41100 & 41700
series valves without Seal Ring
C. Slide the cage (15) over top of plug-stem
sub-assembly.
D. Lower plug (14) and cage (15) into the
body until they rest squarely on the seat
ring (16).
Plug & Cage Assembly for 41200 series
valves with self Energised Static Seal Ring
41400 / 41500 / 41600 / 41900 41300 41200
C. Insert the cage into the body on the seat.
Place the Tec Seal ring with the lips
facing upwards.
D. Place the clamping cage over the main
cage. Then put plug with stem into cage
until it rests squarely on seat ring. Care
should be taken not to damage the seal
ring.
Plug & Cage Assembly for 41300 series
valves with self Energised Static Seal Ring
C. Place self energized seal ring (13) over
the top of the plug with the lips facing
upwards and then push down evenly
from all sides until the seal ring slips
into the plug groove.
D. Place cage into the body on the seat. Put
plug with stem into cage until it rests
squarely on seat ring. Care to be taken
not to damage the seal ring.
Caution: For valves with Tec Seal Ring
(41200 & 41300), do not slide cage over
the plug.
Plug & Cage Assembly for 41400 series
valves with Auxilary Pilot Plug
C. This valve has metallic seal rings. Inner
ring has a straight cut while the outer
ring has a staggered cut. To insert the
rings into plug groove, open the ring by
hand and slide them along the plug
without damaging any of the parts.
Assemble the inner & outer rings
separately, in such a way that seal ring
o
openings are 180 apart
D. Assemble the auxiliary pilot plug &
valve plug-stem assembly using the
same procedure for pilot plug
disassembly (6.2.B), compress the
springs so that retaining ring can be
inserted into the plug groove.
Plug & Cage Assembly for 41500 series
valves with Metallic Seal Ring
C. This valve has metallic seal rings. Inner
ring has a straight cut while the outer
ring has a staggered cut. To insert the
rings into plug groove, open the ring by
hand and slide them along the plug
without damaging any of the parts.
Assemble the inner & outer rings
o
separately 180 apart. Slide the cage (15)
over top of plug-stem sub-assembly.
Care to be taken not to damage the seal
rings.
D. Lower plug (14) and cage (15) into the
body until they rest squarely on the seat
ring (16).
10