Magnetrol Tuffy User manual

TUFFY®
Liquid Level Controls
with Pneumatic Switches
®
INSTRUCTION MANUAL AND PARTS LIST
DESCRIPTION
Tuffy liquid level switches are designed for horizontal mount-
ing in a tank or vessel through threaded or flanged pipe con-
nections. Standard models are equipped with a three-
port/two-position valve, actuated by a magnetically actuated
pivoted cam mechanism. This instruction manual covers
Tuffy level controls which have pneumatic switches. For
Tuffy controls with electric switches, please consult Bulletin
BE 44-605.
OPERATING PRINCIPLE
Figures 1 and 2 illustrate the simple Magnetrol operating
principle. Switching action is obtained through the use of a
magnet attached to a float and a switching mechanism.
These two basic component assemblies are separated by a
non-magnetic, pressure tight barrier.
APPLICATIONS
Tuffy is recommended as a high or low alarm switch for
clean liquid applications only.
(For Tuffy controls with electric switches, consult bulletin BE 44-605)
OPERATING CYCLE
At a “low operating level” of liquid in a tank or vessel (refer
to Figure 1), the float moves the magnet upward and into
the field of the switch mechanism magnet. As a result, the
magnets repel causing the pivot arm and valve plunger to
move so that air is allowed to pass from air inlet A to air out-
let C. As liquid level rises, for “High Operating Level” indi-
cation (refer to Figure 2), the float moves the magnet down-
ward until the switch mechanism magnet reverses position,
allowing the valve plunger to move so that air is allowed to
pass from air inlet B to air outlet C.
For direct acting low level operation, air inlet A is closed off
when liquid level increases. Conversely, for direct acting
high level operation, air inlet B is closed off when liquid level
recedes.
For reverse acting operation, air inlet A is used for high level
and air inlet B is used for low level. The air inlet that is not in use
should be plugged to prevent foreign materials from entering.
UNPACKING
Unpack the instrument carefully. Inspect all units for dam-
age. Report any concealed damage to carrier within 24
hours. Check the contents of the packing slip and purchase
order. Check and record the serial number for future refer-
ence when ordering parts.
MODEL IDENTIFICATION
Air inlet B
(no air flow)
Air inlet A
Valve body Air outlet C Pivot arm
Falling level
Float
Pivot
Magnets
Magnet
pivot Tuffy body
(non-magnetic)
Spring
Valve
plunger
Figure 1: Low level operation – direct acting
Air inlet B
Air inlet A
(no air flow)
Valve body Air outlet C Pivot arm
Rising level
Float
Pivot
Magnets
Magnet
pivot Tuffy body
(non-magnetic)
Spring
Valve
plunger
Figure 2: High level operation – direct acting
SPECIFIC GRAVITY
PNEUMATIC SWITCH
0 0,6 minimum
4 0,4 minimum
0 00 09 1 03 6

2
INSTALLATION
EXTERNAL CAGE INSTALLATION
MOUNTING
1. Before assembling Tuffy in a tank or vessel, check
threaded or flanged mounting nozzle for the following:
a. Nozzle length and inside diameter must be sized
correctly to allow for switch actuation at design
levels. Refer to Figure 3.
b. Nozzle must be checked for horizontal alignment.
2. Tuffy mounting does not differ for high level or low level
operation. For proper operation, the serial number tag
must be on top. Depending on whether direct or indi-
rect action is required, air inlet A or air inlet B are used
for supply air input. Air outlet C is always used for out-
put. Table 1 summarizes the pneumatic valve action
that takes place based on the inlets used.
3. Inlet air should be filtered with a 5 micron or finer filter.
This will extend the life of the valve mechanism.
4. Connect the inlet air line to the 1⁄4" NPT connection for
either air inlet A or air inlet B, depending on the valve
action desired (refer to Table 1). Inlet air pressure
should be between 0–13.8 bar (0–200 PSIG). Refer to
Figure 3 for location of air inlets.
5. Connect outlet air line to the 1⁄4" NPT connection on
the bottom of the valve. This air outlet is designated
with a “C”. Refer to Figure 3 for location.
6. If 3-way function is used, attach the exhaust air line to
the appropriate 1⁄4" NPT connection based on valve
action described in Table 1.
Table 1
N.O.—Direct Acting: Air supply on switch condition.
N.C.—Reverse Acting: Air cut-off on switch condition.
Float 2-Way 2-Way 3-Way 3-Way
Position Port N.O. N.C. N.O. N.C. Diverter Selector
(direct) (reverse) (direct) (reverse)
Down A Inlet Plug Inlet Exhaust Outlet Outlet
(Low)
Up B Plug Inlet Exhaust Inlet Outlet Inlet
(High)
— C Outlet Outlet Outlet Outlet Inlet Outlet
Float must clear
inner tank wall
Serial No.
Tag
1/4" NPT
inlet (B)
1/4" NPT
inlet (A)
1/4" NPT
outlet (C)
Wrench flats
Figure 3
C
L
Shutt-off
Valve
Pressure
Vessel
Switch
Actuation
Level
Shutt-off
Valve
Drain Valve
Safety
Check
Valve
1/4" NPT
inlet (B)
1/4" NPT
inlet (A)
1/4" NPT
outlet (C)
Figure 4
Figure 4 shows a typical piping installation of a Tuffy Exter-
nal Cage Assembly. Switch actuates within 19 mm (0.75")
above the cage-Tuffy centerline for rising level and within
19 mm (0.75") below the centerline on falling level.
The external cage must be installed so that the tappings
are vertical. Installation should be checked with a spirit
level on top and/or sides of the cage.
Controls should be mounted as close to the vessel as pos-
sible. This will result in a more responsive and accurate
level change in the cage. Liquid in a long pipeline may be
cooler and more dense than liquid in a vessel causing lower
level indication in the control than actual level in the vessel.
Use pipe of sufficient strength to support the control. If nec-
essary, provide a stand or hanger to help support its
weight. All piping should be straight and free of “low spots”
or “pockets” so that lower liquid will drain towards the ves-
sel and upper vapor line will drain toward the control. Shut-
off valves are recommended for installation between the
vessel and the cage assembly. If a control is to be used with
a low temperature liquid (one which will “boil” in the float
chamber if outside heat is absorbed), the chamber and pip-
ing should be insulated. Such boiling in the chamber will
cause false level indicators. In this case, DO NOT insulate
the switch mechanism housing.

C
L
3
PREVENTIVE MAINTENANCE
TROUBLESHOOTING
SPECIFICATIONS
WHAT TO AVOID
1. Use only the 2" wrench flats to install or remove the
unit. Refer to Figure 3. Use of any other surface could
change the calibration. The valve body is calibrated at
the factory and locked in place.
Periodic inspections are a necessary means to keep your Magnetrol level control in good working order. This control is a safety
device to protect the valuable equipment it serves. A systematic program of preventive maintenance should be implemented
when the control is placed into service. Based on utilizing a preventative maintenance program and observing the following sec-
tion on “what to avoid”, your Tuffy will provide reliable protection of your capital equipment for many years.
2. NEVER attempt to make adjustments without reading
the instructions carefully. When in doubt, consult the
factory or your local representative.
3. NEVER use in systems which have excess iron parti-
cles in the solution. The magnet at the counterweight
end of the float can attract the particles which could
cause the float rod to jam.
FAILURE TO SHUT OFF OR TURN ON INLET AIR
1. Check float for full range of travel; clicking of mecha-
nism should be heard.
2. If the complete Tuffy mechanism operates properly
when removed from service, check to be certain that
liquid is entering the storage tank or vessel. A valve
may be closed or a pipe line clogged.
3. If the float is determined to be filled with liquid or is
collapsed, the entire level switch must be replaced. Do
not attempt to repair the float.
4. The factory calibration setting should not require any
adjustment in the field. Check to see that the unit is
installed properly with the serial number tag posi-
tioned on the top of the unit. If the unit is still not oper-
ating correctly, please contact the factory.
NOTE: When in doubt about the condition or performance
of a control, please contact the factory for assistance.
Description Specification
Max. design pressure 0,6 SG: 103 bar @ 040°C (1500 PSIG @ 100°F)
0,4 SG: 34 bar @ 040°C (1500 PSIG @ 100°F)
Max. process temperature -40°C to 200°C (-40°F to 400°F)
Pneumatic switch supply pressure Vacuum - max 13.8 bar (200 PSIG)
Max. leakage rate 14.16 l/h (0.5 SCFH)
Max. air flow 2.55 m3/h (1.5 SCFM)
Specific gravity 0.6 minimum or 0.4 minimum
Materials of construction 316/316 SS wetted components including ANSI B 31.3/NACE
Housing 316/316 L SST
Cage (optional) Carbon steel or 316/316L stainless steel
Cage rating 103 bar @ 260°C (1500 PSIG @ 500°F)
Square flange (optional) rating 017 bar @ 204°C (0250 PSIG @ 400°F)
MECHANICAL SPECIFICATIONS
DIMENSIONAL SPECIFICATIONS in mm (inches)
329 (12.94)
76 (3) max.
nozzle length
2" NPT
1/4" NPT
outlet (C)
1/4" NPT
inlet (B)
1/4" NPT
inlet (A)
Switch Actuates
Rising Level
Falling Level
Switch Actuates
64 (2.5) Ø
19
(0.75)
95 (3.75)
float
minimum
clearance
226 (8.91) [Sp. Gr. 0.4 Min.]
Float Size = 51 (2) Ø x 130 (5.12) Long
202 (7.96) [Sp. Gr. 0.6 Min.]
Float Size = 51 (2) Ø x 116 (4.57) Long

IMPORTANT
SERVICE POLICY
Owners of Magnetrol products may request the return of a control; or, any part of a control for complete rebuilding or replacement. They will be
rebuilt or replaced promptly. Magnetrol International will repair or replace the control, at no cost to the purchaser, (or owner) other than trans-
portation cost if:
a. Returned within the warranty period; and,
b. The factory inspection finds the cause of the malfunction to be defective material or workmanship.
If the trouble is the result of conditions beyond our control; or, is NOT covered by the warranty, there will be charges for labour and the parts
required to rebuild or replace the equipment.
In some cases, it may be expedient to ship replacement parts; or, in extreme cases a complete new control, to replace the original equipment
before it is returned. If this is desired, notify the factory of both the model and serial numbers of the control to be replaced. In such cases, cred-
it for the materials returned, will be determined on the basis of the applicability of our warranty.
No claims for misapplication, labour, direct or consequential damage will be allowed.
RETURNED MATERIAL PROCEDURE
So that we may efficiently process any materials that are returned, it is essential that a “Return Material Authorisation” (RMA) form will be
obtained from the factory. It is mandatory that this form will be attached to each material returned. This form is available through Magnetrol’s
local representative or by contacting the factory. Please supply the following information:
1. Purchaser Name 4. Desired Action
2. Description of Material 5. Reason for Return
3. Serial Number 6. Process details
All shipments returned to the factory must be by prepaid transportation. Magnetrol will
not accept collect shipments.
All replacements will be shipped FOB factory.
BELGIUM Heikensstraat 6, 9240 Zele
Tel. [phone] Fax [phone]
DEUTSCHLAND Schloßstraße 76, D-51429 Bergisch Gladbach-Bensberg
Tel. [phone] Fax [phone]
FRANCE 11, Rue A. Einstein, Espace Descartes, 77420 Champs-sur-Marne
adresse postale: 77436 Marne-la-Vallée Cédex 2
Tel. [phone] Fax [phone]
ITALIA Via Arese 12, I-20159 Milano
Tel. [phone] (R.A.) Fax [phone]
UNITED Unit 1 Regent Business Centre
KINGDOM Jubilee Road Burgess Hill West Sussex RH 15 9TL
Tel. [phone] Fax [phone]
INDIA B4/115 Safdurjung Enclave, New Delhi 110 029
Tel. [phone] Fax [phone]
®
BULLETIN N°: BE 44-606.3
EFFECTIVE: JANUARY 1998
UNDER RESERVE OF MODIFICATIONS SUPERSEDES: March 1991
REPLACEMENT PARTS
Optional accessories
For selection of cages and flanges please refer to bulletin
BE 44-118.
The pneumatic Tuffy is designed for years of trouble free
use. Due to the nature of the valve design and the factory
calibration required for proper operation, no specific
replacement parts are offered.