Singer Valve 106-PG, A206-PG, 206-PG, S106-PG, S206-PG Installation, Operating And Maintenance Instruction

MODEL 106/206-PG POWER OPERATED GLOBE VALVE

Sizes 1/2" to 8" (106-PG) 3" to 10" (206-PG)

DESCRIPTION:

This valve is the basic component used for most Singer
Model 106/206 Automatic Valves. It is a hydraulically
operated valve.

DESCRIPTION OF OPERATION:

The valve opens when the bonnet (area above the
diaphragm) is connected to the downstream side of the
valve AND a pressure drop of 5 psi (35 kPa) is available
across the valve. The valve also opens when the
bonnet is vented to atmosphere, regardless of pressure
drop, provided that the line pressure is 5 psi (35 kPa) or
more.

The valve closes when the inlet pressure is directed to
the bonnet.

The valve can be made to modulate by varying the
bonnet pressure between inlet pressure and outlet
pressure. This is done by the pilot circuit.

In some cases the line media is unsuitable for use in
the pilot system. In these circumstances external water
pressure can be used in the pilot system. The external
pressure must be equal to or higher than the line
pressure.

If available pressure drop is less than 5 psi (35 kPa),
spring lift and external water pressure must be used
(consult factory).

Unless otherwise specified, the valve is assembled with
components suitable for water service up to 180
C). For other service conditions, contact your Singer
Valve representative.

STORAGE:
This valve must be stored indoors, away from direct

sunlight.
INSTALLATION:
Use washers under nuts when bolting valve flanges

to pipe flanges to protect the Epoxy Coating.

Control valves must be installed in a horizontal pipe
with the bonnet up. Smaller valves (6” and smaller) can
be installed in a vertical pipe if the order states the
orientation. Disassembly is difficult but not impossible in
valves installed in vertical pipe.

A stable, non-failing source of pressure is necessary to
operate a pilot operated control valve.

Installation, Operating and Maintenance Instructions

Operating fluid must be clean and free of air.
Under high velocity conditions the pressure signal,

when the pick-up point is located on the main valve
inlet, may be adversely affected. As an example, a relief
valve will operate more effectively and control more
accurately if the operating pressure and sensing
pressure is connected to the header.

Ideally, six pipe diameters of straight pipe is required on
the inlet of any control valve but

• Fully open Gate Valve can be installed on the inlet
of a valve, provided it is used as an isolating valve
and never used in partially open condition.

• A Butterfly Valve with stem horizontal can not
installed in the inlet of a control valve unless
operating pressure and sensing lines are connected
upstream of the butterfly valve, in a location that
gives true system pressure.

• A Butterfly Valve with stem vertical can be
installed in the inlet of a control valve as long as
velocity does not exceed 15 ft/sec. The butterfly
valve can not be used for throttling. If problems
develop at high flows, operating pressure and
possible sensing can be connected upstream of the
butterfly valve, in a location that gives true system
pressure.

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IOM 224A Page 1 of 2 June 2007

• A control valve can be installed with no straight pipe
on the inlet if the operating and sensing lines are
connected to a location that gives true system
pressure.

The connection point should be made at the pipe
centerline to avoid air pick-up at the top of the pipe.

1. It is possible that diaphragms may take a set

after shipping and storage. It is highly
recommended that Bonnet and Body Bolts or
Nuts be tightened after installation but before
pressurizing the valve. If a leak develops after
pressurizing, de-pressurize the valve and
tighten the bolts or nuts.

2. For most convenient operation and maintenance,
line isolation valves should be installed.

3. A suitable bypass should be provided to allow for
servicing of the valve without interrupting the flow.

Surrey, BC. Canada. V3W 3H9

12850-87th Avenue

Ph: 604-594-5404

Fx: 604-594-8845

www.singervalve.com

be

Installation (Cont.):

4. Install pressure gauges upstream and/or
downstream of valve as appropriate. This will
facilitate ease of setting the pilot system.

5. A strainer with a suitable basket should be installed
ahead of the valve to protect it from foreign
material.

6. Sufficient space should be provided around the
valve for disassembly.

7. Flush system of all foreign matter before installing
the valve.

8. Check direction of flow (inlet of valve is marked OR
an arrow on the side of body indicates flow
direction) and install the valve accordingly.

VENT AIR FROM THE BONNET. After installation,

9.
when the valve is pressurized, vent air from the
bonnet:

a) Valves installed in horizontal piping with bonnet up

(NO LIMIT SWITCH):
Sizes up to 2" where pilot connection is to the guide
bushing at the center of the valve do not require
venting (they vent automatically).
Sizes up to 2" with position indicator: use bleed-cock
on indicator.
Sizes 2-1/2" and larger, loosen pipe plug at the
center of the bonnet to bleed air. If equipped with
position indicator, use bleed-cock on indicator.

b) Valves installed in horizontal piping with bonnet up

(WITH LIMIT SWITCH): Refer to Drawing A0707A.
Use bleed screw (63) to vent air.

c) Valves installed in vertical pipe: The pilot connection

will be to the highest point on the bonnet if the
orientation and flow direction were specified on the
order. Some sizes vent automatically. Some sizes
are provided with a small screw to facilitate bleeding
(do not remove completely).

d) Valves that do not have the bleed screw and do not

bleed completely from existing connections must be
bled by loosening the bonnet bolts.

SERVICE SUGGESTIONS:

POSSIBLE CAUSE / REMEDY
FAILS TO OPEN

1. Insufficient inlet pressure. / Increase pressure

IOM 224A Page 2 of 2 June 2007

Surrey, BC. Canada. V3W 3H9

2. Pressure in the bonnet is not released:

• Isolating valves on pilot lines closed. - Open valves

12850-87th Avenue

Ph: 604-594-5404

Fx: 604-594-8845

www.singervalve.com

• Pilot components not functioning. - Refer to specific
instructions on pilot components

• Foreign material in pilot system. - Clear obstruction

FAILS TO CLOSE
Lack of pressure in the bonnet due to:

• Pilot components not functioning. - Refer to specific
instructions on pilot components.

• Foreign material in pilot system.

• Ruptured diaphragm.

• Obstruction in the valve.

• Worn main valve disc.

PULSATIONS

• Air in the bonnet. - Vent air. Refer to "Installation
(9)" above.

• Improper adjustment to pilot components. - Refer to
specific instructions on pilot components.

• Valve oversized. A smaller valve in parallel may be
required.

MAINTENANCE:

The SINGER Model 106/206-PG requires a minimum of
maintenance. All parts are accessible for inspection
and repair without removing the valve from the line.

1. Close upstream and downstream isolating gate
valves.

2. Disconnect body and bonnet pilot lines.

3. Remove bonnet. If bonnet does not come free
readily, it can be pried loose with a small pry-bar.

4. Remove main valve assembly for inspection. Do
not remove seat ring unless inspection shows that it
is damaged.

5. Replace worn or defective parts and reassemble.

NOTE REGARDING FREEZING:

This valve does not drain completely when inlet and
outlet pipes are drained. Where freezing conditions are
expected, one of the following must be performed:

• Drain valve and pilot system completely.

• Add suitable anti-freeze to valve and pilot system

(Non-potable water service only).

• Provide insulation and/or heating to keep the valve
from freezing.