Groth 3000 Series User Manual

Page 4

REGULATOR DESIGN, FUNCTION &
OPERATION

The Groth Model 3000 Regulator is a high capacity
spring operated, diaphragm type, balanced piston
regulator design for tank blanketing applications.

The regulator controls the flow of blanketing gas to
the vapor space in the storage tank. When the
internal pressure of the tank is at or above set
pressure, the diaphragm force exceeds the spring
force and the regulator is shut off bubble tight.
When the tank pressure falls below the set point, the
spring force opens the regulator and blanket gas
flows into the tank (See Figures 2 and 3).

The regulator must be sized to provide sufficient
blanket gas to prevent the loss of tank pressure due to
liquid discharge or decreased ambient temperature.
Table 2 lists the maximum flow capacity of the
regulator for various blanketing gases. Actual
system flow will depend on supply system piping,
tank connection piping and position of the internal
orifice sleeve. Set pressure is the pressure at which
the regulator begins flowing when tank pressure is
decreasing and stops flowing when tank pressure is
increasing.

This manual is intended to provide recommended
procedures and practices for installation, operation,
and maintenance of the Groth Series 3000 Regulator.
Any standard procedures and practices developed in
a specific plant or process should supersede this
manual. Although this manual cannot cover all
possible contingencies, following these guidelines

hould provide safe regulator performance.

Note that throughout this manual, the item numbering
is listed in [ ] after the part description. Refer to the
exploded assembly drawing on page 15 and the parts
list on page 16.

TABLE 1

REGULATOR SPECIFICATIONS

3000

3010

3020

Flow
Coefficient
(CV)

12.5 12.5 12.5

Inlet/Outlet

1" NPT (F)
or
1"150# RF
Flange

1" NPT (F)
or
1" 150# RF
Flange

Supply Pressure

200 PSI

Tank Pressure

2" WC to
2.0 PSI

1/2" WC to
2" WC

1 PSI to

10 PSI

Max. Tank
MAWP

25 PSI

10 " WC

150 PSI

TABLE 2

FLOW CAPACITY *

3000 SERIES REGULATOR SCFH

Supply

Pressure

PSI

Nitrogen Natural

Gas

0.6 G

Air

10
15
20
30
40
50
60
80

100
120
140
160
180
200

5700
8700

11300
13800
18600
23200
27700
32100
40700
49300
57900
66500
75100
83700
92300

5800
8800

11500
14000
18900
23600
28200
32600
41300
50100
58800
67500
76300
85000
93700

7400

11300
14600
17900
24000
30000
35800
41500
52600
63700
74800
85900
97000

108100
119200

Internal orifice sleeve installed in 100% flow capacity

position.

For information not contained in this manual, please
contact:

Groth Corporation

Groth Products Group

P. O. Box 15293

Houston, TX. 77220

713-675-6151 (phone)

713-675-6739 (fax)