Emerson Y695VR Data Sheet

Bulletin 71.3:Y695VR

Y695VR Series Vacuum Regulator

W7295

January 2009

Figure 1. Type Y695VR Vacuum Regulator

Introduction

The Y695VR Series direct-operated vacuum regulators are used where a decrease in vacuum must be limited,
such as between a tank and vacuum source to control vacuum in tank. The Type Y695VR has internal pressure
registration. The Type Y695VRM has a control line connection and blocked throat for external pressure registration.

Features

•   Tamper Resistant Adjustment—Closing cap
and spring case on many types allow installation
of sealing wire to discourage or detect
unauthorized adjustment of pressure setting.

•   Precision Control of Low Pressure Settings—
Large diaphragm areas provide more accurate
control at low pressure settings.

  •   Easy Conversion—The Y695VR Series Vacuum

Regulators are easily adapted between external
and internal registration.

•   Common Spare Parts—The Type Y695VR and
Type Y695VRM share common spare parts with
the other Y690A Series products.

•   Corrosion Resistance—Constructions are
available in a variety of materials for compatibility
with corrosive process gases.

www.emersonprocess.com/regulators

D102597X012

Bulletin 71.3:Y695VR

Specications

Available Congurations

Type Y695VR: Direct-operated vacuum regulator
Type Y695VRM: Direct-operated vacuum regulator

with blocked throat for external pressure registration

Body Sizes and End Connection Styles

BODY SIZE,

INCHES (DN)

3/4 or 1 (20 or 25) NPT

  1.  Weld-on ange dimension is 14-inches (356 mm) face-to-face.

Maximum (Casing) Pressure

END CONNECTION STYLES

Ductile Iron Steel or Stainless Steel

(2)

(1)

NPT, SWE,

or CL150 RF

Full Vacuum

Maximum Downstream Pressure

(2)

Full Vacuum

Change in Control Pressure to Wide-open

(2)

See Table 2

Pressure Registration
Type Y695VR: Internal
Type Y695VRM: External

Orice Size
7/16-inch (11 mm)

Capacities
See Table 2

    1.  End connections for other than U.S. standards can usually be provided; consult the local Sales Ofce.

2. The pressure/temperature limits in this bulletin and any applicable standard or code limitation should not be exceeded.

Flow Coefcients

Cg: 120
Cv: 3.43
C1: 35

Material Temperature Capabilities

Nitrile (NBR): -20° to 180°F (-29° to 82°C)
Fluorocarbon (FKM):
40° to 300°F (4° to 149°C)
Peruoroelastomer (FFKM):

-20° to 300°F (-29° to 149°C)

Spring Case Connection
1/4-inch NPT

Diaphragm Case Connection
1/2-inch NPT

Construction Materials
See Table 1

Pressure Setting Adjustment
Adjusting nut

Additional Options
Umbrella vent assembly for spring
case connection

Approximate Weight
19 pounds (9 kg)

(2)

BODY SPRING CASE DIAPHRAGM CASE TRIM DIAPHRAGM DISK

Ductile iron, CF8M Stainless

steel, or Hastelloy® C

SPRING RANGE,

PART NUMBER,

AND COLOR

0 to 4-inches w.c.

(0 to 10 mbar)
0N039427222

Unpainted

0.05 to 0.75 psig

(0,003 to 0,05 bar)

0N086027022

Unpainted

0.15 to 1.75 psig

(0,01 to 0,12 bar)

0N086127022

Unpainted

0.25 to 2.75 psig

(0,02 to 0,19 bar)

0N022027022

Dark green

1.5 to 4.75 psig

(0,10 to 0,33 bar)

0N004327022

Yellow

3.0 to 12.8 psig

(0,21 to 0,88 bar)

1D141827012

Dark blue

SPRING WIRE

DIAMETER

0.062-inches
(1,57 mm)

0.105-inches

(2,67 mm)

0.125-inches
(3,18 mm)

0.135-inches
(3,43 mm)

0.172-inches
(4,37 mm)

0.207-inches
(5,26 mm)

Ductile iron or

CF8M Stainless steel

MAXIMUM

ALLOWABLE

VACUUM

5.1 psig (0,35 bar)

5.7 psig (0,39 bar)

6.5 psig (0,45 bar)

7.4 psig (0,51 bar)

9.2 psig (0,63 bar)

12.0 psig (0,83 bar)

Table 1. Construction Materials

Ductile iron or

CF8M Stainless steel

316

Stainless steel

Table 2. Y695VR Series Capacities

CONTROL

PRESSURE

SETTING VACUUM

2-inches w.c.

(5 mbar)

0.5 psig

(0,03 bar)

1 psig

(0,07 bar)

2 psig

(0,14 bar)

4 psig

(0,28 bar)

9 psig

(0,62 bar)

OUTLET

VACUUM

7.5 psig

(0,52 bar)

7.5 psig

(0,52 bar)

7.5 psig

(0,52 bar)

7.5 psig

(0,52 bar)

7.5 psig

(0,52 bar)

12 psig

(0,83 bar)

Nitrile (NBR) or

Fluorocarbon (FKM)

CHANGE IN

CONTROL PRESSURE

TO WIDE-OPEN

1-inch w.c. (2 mbar) 1650 (44,2)

5.5-inches w.c. (14 mbar) 1614 (43,3)

0.44 psig (0,03 bar) 1578 (42,3)

0.63 psig (0,04 bar) 1464 (39,2)

1.44 psig (0,10 bar) 1290 (34,6)

3.88 psig (0,27 bar) 1140 (30,6)

Nitrile (NBR) or

Fluorocarbon (FKM)

CAPACITY IN SCFH

(Nm³/h) OF 1.0

SPECIFIC GRAVITY AIR

2

Principle of Operation

B2582

VACUUM BEING

CONTROLLED

HIGHER

VACUUM SOURCE

VACUUM

PUMP

INLET PRESSURE (VACUUM)
OUTLET PRESSURE (VACUUM)
ATMOSPHERIC PRESSURE (VACUUM)

The Y695VR Series vacuum regulators are used
to maintain a constant vacuum at the regulator
inlet. A decrease in this vacuum (increase in
absolute pressure) beyond this value registers on
the diaphragm and opens the disk. This permits a
downstream vacuum of lower absolute pressure than
the upstream vacuum to restore the upstream vacuum
to its original pressure setting. On the Type Y695VR,
pressure registers underneath the diaphragm. The
Type Y695VRM has a control line connecting the
diaphragm casing to the vacuum line and an O-ring
stem seal blocking the throat causing pressure to
register through the control line.

Capacity Information

To determine the ow capacities for the Y695VR Series 

vacuum regulators, use the following formula:

Bulletin 71.3:Y695VR

Q = P

1abs Cg

SIN

3415

C

∆P

Deg.

P

1

1abs

where,
  Q   = ow capacity in SCFH (60°F and 14.7 psia) of
air at 60°F
P

= absolute inlet pressure in psia (P1 gauge + 14.7)

1abs

Cg   = ow coefcient (from specications table)
C1 = 35

 ∆P  = pressure drop across vacuum breaker 

or regulator

Note

If the actual change in (control) pressure
(from the service conditions) is less
than the minimum change in (control)
pressure required to fully open the
vacuum regulator (Table 2), the Cg in the
formula must be reduced accordingly.
To obtain the correct reduced Cg,
multiply the Cg from specications
table by the ratio of the actual change
in (control) pressure to the minimum
change in (control) pressure required to
fully open the vacuum regulator.

Conversion Factors

To determine equivalent capacities of natural gas,
propane, butane, or nitrogen, multiply the calculated
capacity by the following appropriate conversion
factor: 1.29 for natural gas, 0.810 for propane,

0.707 for butane, or 1.018 for nitrogen. For gases of

Figure 2. Type Y695VR Operational Schematic

other specic gravities, divide by the square root of 
the appropriate specic gravity.  Then, if capacity is

desired in normal cubic meters per hour at 0°C and

1.01325 down to allow condensate to drain. On indoor
installations, this connection should be piped outdoors
if used in hazardous gas service. External dimensions
and connections are shown in Figure 3.

Note

Downstream piping will vary with the
installation, but to obtain the calculated
characteristics, the pipe should be the
same size as the outlet and should be

straight for the rst 18-inches (457 mm).

Ordering Information

When ordering, specify:

Application

  1.  Composition and specic gravity of gas (including   

chemical analysis if possible)

  2.  Range of temperatures, owing inlet pressures    

(maximum, minimum, nominal), and pressure drops

3. Desired pressure setting or range

4.  Range of ow rates (minimum controlled, 
maximum, normal)

5. Piping size(s)

3

Bulletin 71.3:Y695VR

6.04

(153)

A

B

8.38

(213)

DIAMETER

D

B2441

BODY SIZE,

INCHES (DN)

3/4, 1 (20, 25) 4.00 (102) 4.12 (105) 2.12 (53,8) 2.25 (57,2) 6.19 (157) 6.19 (157) 10.38 (264) 10.38 (264) 1.69 (42,9) 1.69 (42,9)

Ductile

Iron NPT

A B D F G

Stainless

Steel NPT

F

NPT FLANGED

Ductile

Iron

Stainless

Steel

G

DIMENSIONS, INCHES (mm)

Ductile

Iron

Stainless

Steel

Ductile

Iron

Stainless

Steel

14

(356)

Ductile

Iron

INCHES

(mm)

Stainless

Steel

Figure 3. Y695VR Series Dimensions

Construction

Refer to the Specications section and to each 

referenced table; specify the desired selection

Industrial Regulators

Natural Gas Technologies

whenever there is a choice to be made. Always be
sure to specify the type number and the spring case
connection location from Figure 3.

TESCOM

Emerson Process Management
Regulator Technologies, Inc.

USA - Headquarters
McKinney, Texas 75069-1872 USA
Tel: [phone]
Outside U.S. 1-972-548-3574

Asia-Pacic

Shanghai, China 201206
Tel: [phone]

Europe
Bologna, Italy 40013
Tel: [phone]

Middle East and Africa
Dubai, United Arab Emirates

Emerson Process Management
Regulator Technologies, Inc.

USA - Headquarters
McKinney, Texas 75069-1872 USA
Tel: [phone]
Outside U.S. 1-972-548-3574

Asia-Pacic

Singapore, Singapore 128461
Tel: [phone]

Europe
Bologna, Italy 40013
Tel: [phone]
Gallardon, France 28320
Tel: [phone]

Emerson Process Management
Tescom Corporation

USA - Headquarters
Elk River, Minnesota 55330-2445 USA
Tel: [phone]

Europe
Selmsdorf, Germany 23923
Tel: [phone]

Tel: [phone]

For further information visit www.emersonprocess.com/regulators

The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their prospective owners. Fisher is a mark owned by Fisher Controls, Inc., a
business of Emerson Process Management.

The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or

guarantees, express or implied, regarding the products or services described herein or their use or applicability. We reserve the right to modify or improve the designs or specications of such

products at any time without notice.

Emerson Process Management does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Emerson
Process Management product remains solely with the purchaser.

©Emerson Process Management Regulator Technologies, Inc., 1999, 2009; All Rights Reserved