General Information Blower Silencers
In a closed blower discharge system,
shell externally and reduce any shell noise
2.1
structure-borne noise—such as that radiated
contribution to below the casing and mechanical
by pipe wall and silencer shell—may be a
noise of the blower and driving machinery.
consideration, particularly where a stringent,
Universal Silencer invites your inquiries
close-proximity noise specification applies.
concerning special applications where EPA,
General
For these applications, various means are
OSHA or other noise specifications apply.
available to treat the pipe and shell radiated
Special applications are handled on an
y Positive
Information
noise, such that most reasonable
individual basis and recommendations are
specifications may be met.
made according to specific requirements of
Rotar Blower Silencers Blower Silencers
Blower Silencers
For instance, it is possible to lag the silencer
the installation.
10
9
Rotary Positive Blowers
Discharge Silencers
The Rotary Positive Blower is a two impeller
tubes, a more sophisticated silencer design.
For the more severe discharge conditions of
compressor that delivers a large quantity of
is the combination chamber-absorptive type.
typical blower installations, a PLV of
gas or air relative to the individual pulses.
This combination silencer is similar to the
2,700 ft/min is accepted as the critical
Blower capacities are expressed in CFM at
reactive type with the exception that an
transition speed. Blowers operating below
inlet conditions (ICFM). Blower size is usually
acoustically-packed, sound absorbing
2,700 ft/min are considered subcritical and
expressed as gear diameter by rotor length.
section is included, comprising an extension
can usually be adequately silenced on the
Pitch Line Velocity (PLV) is the peripheral
of the silencer connection closest to the
discharge side by use of a chamber-type
velocity of the timing gear—equal to the
blower. The inlet of a discharge silencer and
silencer UCD or URD Series. Machines
product of the gear circumference and the
the outlet of an inlet silencer are the ends
operating above the 2700 ft/min transition
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rotative speed of the blower, usually
having the packed section.
speed will require combination chamber-
2
expressed in feet per minute (FPM).
A third basic type of silencer—the simple,
absorptive silencers such as SD or RD Series.
The blower presents two problems:
straight-through packed type—is occasionally
In some larger blower installations, piping
1
1) pulsation within the piping system and,
used on blowers. This type of silencer is usually
requirements or space restrictions may
2) noise radiation in the vicinity of the blower
used on small, high speed machines which
preclude the use of a large, single discharge
and piping.
characteristically produce significant high
silencer such as the SD or RD Series.
The importance of these relative to each other
frequency noise and relatively mild pulsations.
Where two or more blowers discharge into a
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is a function of blower size and speed; both
The PLV is normally the criterion for
common header, individual silencers upstream
increase proportionately to the blower size
silencer type selection. If the blower is
of the header are required to subdue the
and the square of the speed.
operating in the critical PLV range, it will
individual blower pulsations. Otherwise, the
Pulsation is more pronounced on the
generate objectionable high frequency noise
pulsations tend to beat with each other and
.universalsilencer
discharge side. Peak pulse pressures are quite
which may cause shell ring or tank hammer
can be extremely objectionable.
severe and can result in unsilenced discharge
in the piping and silencer. These critical
Note: Silencers should be mounted as close
sound power levels up to 140–145 dB. The
PLV conditions will always require a
to the blower as possible since any piping
inlet, although producing less severe pulsation
combination chamber-absorptive silencer
between the blower and silencer will radiate
and noise, receives equal attention since the
for satisfactory results.
noise. Standard silencer connections are not
inlet is usually open to atmosphere and the
designed to carry external piping or valve
noise much more apparent.
Inlet Silencers
loads, so good piping support practices
For inlet service, a PLV of 3,300 ft/min or
should be used to prevent stresses that
Silencers
greater is considered critical. This transition
cause fatigue and eventual fracture of the
silencer or piping. It is also good practice to
There is little question that silencers are a
speed is empirically established and is
isolate the blower from the silencer with a
necessity on any blower installation.
somewhat arbitrary, however, it is commonly
See pages 1.1–1.3 for ordering information | www
flexible expansion joint. Contact Universal
Regardless of the size or speed of the blower,
accepted that blowers operating at or above
Silencer for special design considerations
silencers of some type are nearly always used.
3,300 ft/min are considered critical for the
purpose of inlet silencer application. Those
where loading is a factor.
In the selection of blower silencers, there are
operating below 3,300 ft/min are considered
two basic considerations: 1) the silencer must
subcritical. Subcritical PLV applications can
Attenuation Curves
be the correct size (i.e., sufficient capacity for
usually be silenced adequately with a
the volume flow) and, 2) the silencer must be
Noise attenuation curves are given for the
chamber-type silencer, such as Universal URB
the proper type for the application. The
various models within this section.
or UCI Series. Blowers operating above the
nominal silencer size need only be based on
The curves represent insertion loss of
critical PLV of 3,300 ft/min will invariably
the gas volume, (i.e., the CFM of the gas or
airborne noise for typical applications under
require the RIS Series combination chamber-
air at the operating conditions). However, the
average conditions. It is not feasible to chart
absorptive type silencer. Inlet Filters or Filter
silencer (design) must be selected with
the expected performance of a silencer over
Silencers are commonly used on blower
consideration of the blower size and
a wide range of applications and conditions,
inlets, either individually or in series with a
operating speed. Complete application and
therefore, the curves must be used with
separate inlet silencer. Please reference the
capacity information is given on page 2.3.
discretion. Structure-borne noise (see
Filters and Filter Silencers section of this
above) may be a consideration and will
There are two types of silencers commonly
catalog for further information.
require separate analysis, since it is not
used on positive blowers: a reactive type
airborne noise and not used for silencer
silencer which consists of a series of
performance rating.
expansion chambers having interconnecting
The silencers shown below are more fully
attenuation. However, blower silencers
2.2
2.2
described on the individual catalog pages.
generally must be constructed more
These units are designed specifically for use
ruggedly to withstand prolonged exposure to
on Rotary Positive Blowers.
severe pulsations produced by the blower.
There are fundamental similarities between
All silencers described are of standard with
blower silencers and other types, particularly
end in, end-out design. Low or high side
General
reciprocating engine silencers, which also
inlet and outlet connections are available
y Positive
require a silencer design that provides
Information
and are described on the individual
effective pulse control as well as noise
catalog pages.
Rotary Positive Blowers
Blower Silencers Rotar
Blower Silencers
10
9
UCI Series
Inlet Silencer
Chamber-type inlet silencer for use on sub-
critical PLV applications. Available in pipe
sizes 8"–30". Smaller sizes use URB Series.
Available with side connections and
mounting brackets.
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2
RIS Series
1
Inlet Silencer
Combustion chamber-absorptive type inlet
silencer for critical PLV applications.
Available in pipe sizes 2"–30". Low or high
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side outlet and mounting brackets available
on most sizes.
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UCD Series
URB/URD Series
Discharge Silencers
Chamber-type discharge silencer for use on
sub-critical PLV applications. Available in
pipe sizes 8"–30". (Smaller sizes use URB
Series). Low, high, or opposed side
connections and mounting brackets available.
See pages 1.1–1.3 for ordering information | www
SD Series
RD Series
Discharge Silencers
Combination chamber-absorptive type
discharge silencers for critical PLV
applications. Available in pipe sizes 2"–30".
Low, high, or opposed side connections and
mounting brackets available on most sizes.
Accessories,
Special Features
Mounting Brackets
Oversize Flanges
Inspection Openings
Special Finishes
Pressure Vessel Construction
Special Materials
2.3
Application,
Silencer Recommendations
As mentioned on page 2.1 pitch line velocity
A From Table 1 determine whether blower
Capacity,
(PLV) is the speed of the timing gear in feet
RPM is above or below the transition
per minute (ft/min). For purposes of silencer
speed for critical PLV.
y Positive
Pressure Drop Data application. PLV is considered “critical” at
B Consult Table 2 for recommended
3,300 ft/min for intake and 2,700 ft/min for
silencer models.
Rotar Blower Silencers Blower Silencers
Blower Silencers
discharge.
Pressure Drop
Table 1 gives transition speeds in RPM.
10
Blowers running at these speeds or greater
The following formulas may be used to
9
will have critical PLV. Operating speeds below
calculate pressure drop through the
transition will be in the sub-critical range.
silencers covered in this catalog.
2
Blowers operating in the sub-critical speed
V
c
Inlet:
P =
range usually require only simple chamber-
4005
1 Blower Transition Speed
type silencers while those in the critical range
(assumes silencer inlet
Transition Speed-RPM
require combination chamber-absorptive type
Blower
is open to atmosphere)
Gear Size
Inlet
Discharge
silencers. If there is doubt, it is best to use
2
P
530
the combination-type silencers. When gear
Discharge: P
V c
2
6,300
5,155
4005
14.7
T
size and operating speeds are known, the
2¹⁄₂
5,040
4,125
proper type silencer is easily selected.
3
4,200
3,435
P = pressure drop through silencer,
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4
3,150
2,575
inches of water
2
5
2,520
2,060
Silencer Size Selection, Capacity
V = air velocity through silencer,
6
2,100
1,720
Table 3 gives the nominal capacity of the
ft/min*
1
7
1,800
1,470
various size silencers. “Size” in this table
c = individual silencer restriction
8
1,575
1,290
refers to the silencer “nominal size,” or its
coefficient—empirical constant
10
1,260
1,030
“inlet size.” Capacities are expressed in inlet
(see Table 4)
12
1,050
860
CFM (ICFM), thus, discharge silencers are
P = discharge pressure, PSIA
14
900
735
rated at higher capacities than inlet silencers
(operating pressure in PSIG + 14.7)
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16
785
645
since the air is compressed to reduced
T = discharge temperature, ˚R
18
700
570
volume at the discharge operating pressure.
absolute (operating temperature in
20
630
515
˚F + 460)
22
570
470
* To calculate velocity through silencer, divide flow in
.universalsilencer
ACFM by cross-sectional area of silencer inlet diameter
24
525
430
in square feet.
2 Silencer Model Specifications
3
Silencer Capacity
Pitch Line
Inlet
Discharge
Capacity (Inlet CFM 14.7 PSIA at 70˚F)
Velocity
Silencer
Silencer
Size
Discharge Silencer
Inlet Silencer
4 PSIG
Below
6 PSIG
8 PSIG
10 PSIG
15 PSIG
Transition
UCI, URB
URB, UCD, URD
1
30
35
40
40
40
45
Above
1¹⁄₂
70
80
85
90
95
105
Transition
RIS
SD, RD
2
120
140
150
160
165
185
2¹⁄₂
190
220
235
245
255
285
See pages 1.1–1.3 for ordering information | www
3
270
320
335
355
370
415
4 Pressure Drop Coefficients
3¹⁄₂
370
430
455
480
505
560
Pressure Drop
4
480
560
600
630
660
735
Model
Coefficient (C)
5
750
880
935
985
1,030
1,150
URB, URBY
4.2
6
1,080
1,260
1,340
1,410
1,480
1,650
UCI, UCIY, UCIH
4.2
8
1,920
2,250
2,390
2,510
2,630
2,940
RIS, RISY, RISH
4.2
10
3,000
3,520
3,730
3,930
4,110
4,590
UCD, UCDY
4.2
12
4,300
5,070
5,370
5,660
5,920
6,600
URD, URDY, URDH
4.2
14
5,900
6,890
7,310
7,700
8,060
8,990
SD, SDY, SDH
4.2
16
7,700
9,000
9,550
10,000
10,500
11,800
RD, RDY, RDH
4.2
18
9,700
11,400
12,100
12,700
13,300
14,900
RDS, SDS, URDS
7.0
20
12,000
14,000
14,900
15,700
16,400
18,400
22
14,500
17,000
18,100
19,000
19,900
22,200
24
17,300
20,200
21,500
22,600
23,700
26,400
26
20,300
23,800
25,200
26,600
27,800
31,000
28
23,500
27,600
29,300
30,800
32,200
36,000
30
27,000
31,700
33,600
35,400
37,000
41,300
Est Temp.
70˚F
115˚F
140˚F
165˚F
190˚F
240˚F
Typical Attenuation Curve
2.4
2.4
50
Attenuation, dB
40
30
Specifications
20
10
UCI Group
y Positive
0
Chamber Type
63
125
250
500
1K
2K
4K
8K
Octave Band Center Frequency, Hz
Inlet Silencer
Blower Silencers Rotar
Blower Silencers
10
The UCI Series Inlet Silencer is a heavy-
125/150 lb ANSI specifications. Exterior
model is designated UCIY Series and the
9
duty, all welded unit constructed of carbon
surfaces receive a shop coat of rust-
high side inlet type is designated UCIH
steel sheet and plate. It provides pulse
inhibitive primer and may be finish painted
Series. The three types are fundamentally
control and silencing for most subcritical
in the field if desired. The UCI Series is the
alike and performance is identical. Mounting
PLV applications. Sizes 8" and larger are
basic inlet model and is the conventional
brackets and other options are available—
equipped with flanged connections drilled to
end-in,end-out version. The low side inlet
see page 2.11.
UCI Series
UCIY Series
UCIH Series
(Low Side Outlet)
(High Side Outlet)
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Chamber Type Inlet Silencers
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Part
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H
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UCIY
UCIH
Weight
(Size)
Number
Min
Max
Min
Max
1
1¹⁄₂
2
See pages 1.1–1.3 for ordering information | www
2¹⁄₂
3
Sizes 1"–6" Use URB Series (page 2.7)
3¹⁄₂
4
5
6
8
53-108-AA
22
61
3¹⁄₂
54
14¹⁄₂
9
21
28¹⁄₂
45¹⁄₂
250
10
53-110-AA
26
74
3¹⁄₂
67
16¹⁄₂
11
27
34¹⁄₂
57
360
12
53-112-AA
30
87
3¹⁄₂
80
18¹⁄₂
12¹⁄₂
34
41
69
550
14
53-114-AA
30
99
3¹⁄₂
92
18¹⁄₂
13¹⁄₂
40
47¹⁄₂
80¹⁄₂
650
16
53-116-AA
36
113
3¹⁄₂
106
21¹⁄₂
15¹⁄₂
48
53¹⁄₂
91¹⁄₂
950
18
53-118-AA
42
126
3¹⁄₂
119
24¹⁄₂
17¹⁄₂
55¹⁄₂
59¹⁄₂
103¹⁄₂
1,200
20
53-120-AA
42
140
4¹⁄₂
131
25¹⁄₂
19
60¹⁄₂
67
114
1,350
22
53-122-AA
48
153
4¹⁄₂
144
28¹⁄₂
20¹⁄₂
66¹⁄₂
75
126
1,950
24
53-124-AA
54
167
4¹⁄₂
158
31¹⁄₂
22¹⁄₂
72
83
138
2,500
26
53-126-AA
54
179
4¹⁄₂
170
31¹⁄₂
23¹⁄₂
85
84
149
2,750
28
53-128-AA
60
193
4¹⁄₂
184
34¹⁄₂
25¹⁄₂
87
91
161
3,400
30
53-130-AA
66
206
4¹⁄₂
197
37¹⁄₂
27¹⁄₂
95
100
173
4,650
Note: Dimensions and weights are nominal and may vary slightly with production models.
Request certified drawings of specific models for exact dimensions.
2.5
Typical Attenuation Curve
50
Specifications
Attenuation, dB
40
RIS Group
30
20
y Positive
Combination Chamber-
10
Absorptive Type
0
63
125
250
500
1K
2K
4K
8K
Rotar Blower Silencers Blower Silencers
Inlet Silencer
Octave Band Center Frequency, Hz
10
The RIS Series Inlet Silencer is a heavy-
Smaller sizes are standard with male
A low side outlet version is designated RISY
9
duty, all welded unit constructed of carbon
threaded pipe nipples. Units sized 4" and 5"
Series and high side outlet configuration is
steel sheet and plate. It features an
are available in either flanged or male pipe
designated RISH Series. The three types are
acoustically-treated outlet and will provide
threads. Exterior surfaces receive a shop
fundamentally alike and performance is
pulse control and silencing suitable for
coat of rust inhibitive primer and may be
identical. Mounting brackets and other
critical PLV applications. Sizes 4" and larger
finish painted in the field if desired.
options are available—see page 2.11.
are equipped with flanged connections
The RIS Series is the basic model, having
drilled to 125/150 lb ANSI specifications.
conventional end-in, end-out configuration.
RIS Series
RISY Series
RISH Series
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(Low Side Outlet)
(High Side Outlet)
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Combination Chamber-Absorptive Type Inlet Silencers
Y
P
Part
K
D
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N
H
E
RISY
RISH
Weight
(Size)
Number
RISY
RISH
Min
Max
Min
Max
1
Sizes 1"–1¹⁄₂" use U5 Series (page 3.2)
1¹⁄₂
2
54-102-AA
8
28¹⁄₂
3
22¹⁄₂
8¹⁄₂
—
—
FIXED AT 6
25
See pages 1.1–1.3 for ordering information | www
2¹⁄₂
54-125-AA
8
33
3
27
9
—
—
FIXED AT 7
2¹⁄₂" THRU 3¹⁄₂"
25
3
54-103-AA
8
39
3
33
10
—
—
FIXED AT 7
AVAILABLE ON
30
3¹⁄₂
54-135-AA
10
39¹⁄₂
3
33¹⁄₂
11
—
—
FIXED AT 8
SPECIAL ORDER
40
4
54-104-AA* 10
45
3
39
12¹⁄₂
14¹⁄₂
2¹⁄₄
7¹⁄₂
16¹⁄₂
30¹⁄₂
32¹⁄₂
50
5
54-105-AA* 12
57¹⁄₂
3
51¹⁄₂
15¹⁄₂
17¹⁄₂
2³⁄₄
9
23
40
43¹⁄₂
80
6
54-106-AA
14
64
3
58
17
20
3¹⁄₄
9
25¹⁄₂
43¹⁄₂
49
110
8
54-108-AA
18
72
3¹⁄₂
65
21¹⁄₂
26¹⁄₂
4
12
30¹⁄₂
49¹⁄₂
54
190
10
54-110-AA
22
85
3¹⁄₂
78
25¹⁄₂
32¹⁄₂
5
13¹⁄₂
37
61¹⁄₂
65¹⁄₂
380
12
54-112-AA
26
98
3¹⁄₂
91
29¹⁄₂
38
6
15
44
69
77
550
14
54-114-AA
30
111
3¹⁄₂
104
30
40
7¹⁄₂
16¹⁄₂
50
81
89¹⁄₂
800
16
54-116-AA
36
113
3¹⁄₂
106
35¹⁄₂
49¹⁄₂
0
18¹⁄₂
51
56¹⁄₂
88¹⁄₂
1,050
18
54-118-AA
42
126
3¹⁄₂
119
41
57¹⁄₂
0
20¹⁄₂
58¹⁄₂
62¹⁄₂
100¹⁄₂
1,350
20
54-120-AA
42
140
4¹⁄₂
131
47
62¹⁄₂
0
22
63¹⁄₂
70
111
1,500
22
54-122-AA
48
153
4¹⁄₂
144
46¹⁄₂
65¹⁄₂
0
23¹⁄₂
69¹⁄₂
78
123
2,100
24
54-124-AA
54
167
4¹⁄₂
158
54
75¹⁄₂
0
25¹⁄₂
75
86
135
2,700
26
54-126-AA
54
179
4¹⁄₂
170
55¹⁄₂
76
0
25¹⁄₂
87
86
147
3,050
28
54-128-AA
60
193
4¹⁄₂
184
61
84¹⁄₂
0
29¹⁄₂
91
95
157
3,850
30
54-130-AA
66
206
4¹⁄₂
197
66¹⁄₂
93¹⁄₂
0
30¹⁄₂
98
103
170
5,150
Note: Dimensions and weights are nominal and may vary slightly with production models.
Request certified drawings of specific models for exact dimensions.
*Specify -TT for male pipe threaded units.
Typical Attenuation Curve
2.6
2.6
50
Attenuation, dB
40
30
Specifications
20
10
UCD Group
y Positive
0
Chamber Type
63
125
250
500
1K
2K
4K
8K
Octave Band Center Frequency, Hz
Discharge Silencer
Blower Silencers Rotar
Blower Silencers
10
The UCD Series Discharge Silencer is a
is not warranted. Sizes 8" and larger are
basic end-in, end-out configuration. A low
9
heavy-duty, all welded unit constructed of
equipped with flanged connections drilled to
side inlet version is designated UCDY Series.
carbon steel sheet and plate. It provides
125/150 lb ANSI specifications. Exterior
The two types are fundamentally alike and
pulse control and silencing for subcritical
surfaces receive a shop coat of rust-
performance characteristics are identical.
PLV applications where the higher
inhibitive primer and may be finish painted
Mounting brackets and other options are
performance of the URD Series on page 2.7
in the field if desired. The UCD Series is the
available—see page 2.11.
UCD Series
UCDY Series
(Low Side Inlet)
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Chamber Type Discharge Silencers
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Part
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H
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Weight
(Size)
Number
Min
Max
1
1¹⁄₂
2
See pages 1.1–1.3 for ordering information | www
2¹⁄₂
3
Sizes 1"–6" use URB Series (page 2.7)
3¹⁄₂
4
5
6
8
56-108-AA
22
61
3¹⁄₂
54
14¹⁄₂
9
21
250
10
56-110-AA
26
74
3¹⁄₂
67
16¹⁄₂
11
27
360
12
56-112-AA
30
87
3¹⁄₂
80
18¹⁄₂
12¹⁄₂
34
550
14
56-114-AA
30
99
3¹⁄₂
92
18¹⁄₂
13¹⁄₂
40
650
16
56-116-AA
36
113
3¹⁄₂
106
21¹⁄₂
15¹⁄₂
48
900
18
56-118-AA
42
126
3¹⁄₂
119
24¹⁄₂
17¹⁄₂
55¹⁄₂
1,200
20
56-120-AA
42
140
4¹⁄₂
131
25¹⁄₂
19
60¹⁄₂
1,350
22
56-122-AA
48
153
4¹⁄₂
144
28¹⁄₂
20¹⁄₂
66¹⁄₂
1,950
24
56-124-AA
54
167
4¹⁄₂
158
31¹⁄₂
22¹⁄₂
72
2,500
26
56-126-AA
54
179
4¹⁄₂
170
31¹⁄₂
23¹⁄₂
85
2,750
28
56-128-AA
60
193
4¹⁄₂
184
34¹⁄₂
25¹⁄₂
87
3,400
30
56-130-AA
66
206
4¹⁄₂
197
37¹⁄₂
27¹⁄₂
95
4,650
Note: Dimensions and weights are nominal and may vary slightly with production models.
Request certified drawings of specific models for exact dimensions.
2.7
Typical Attenuation Curve
Specifications
50
Attenuation, dB
40
URB Group
30
URD Group
20
Note: Sizes 1"–6" are URB Series;
y Positive
10
sizes 8"–30" are URD Series. Both series are
Chamber Type
0
fundamentally the same in design and the
63
125
250
500
1K
2K
4K
8K
Rotar Blower Silencers Blower Silencers
Discharge Silencer
Octave Band Center Frequency, Hz
performance characteristics are identical.
10
The URB/URD Series Discharge Silencer is
nipples. Units sized 4" and 5" are available in
designated URDH Series; and low opposed
9
a heavy-duty, all welded unit constructed of
either flanged or male pipe threads. Exterior
connection is designated URDS Series. The
carbon steel sheet and plate. It provides
surfaces receive a shop coat of rust-
four types are fundamentally alike and
pulse control and silencing for subcritical
inhibitive primer and may be finish painted
performance characteristics are identical.
PLV applications. Sizes 4" and larger are
in the field if desired. The URB/URD Series
Mounting brackets and other options are
equipped with flanged connections drilled to
is the basic end-in, end-out configuration.
available—see page 2.11.
125/150 lb ANSI specifications. Smaller
A low side inlet version is designated
sizes are standard with male threaded pipe
URBY/URDY Series; high side inlet is
URB,
URBY,
URDH Series
URDS Series
URD Series
URDY Series
(High Side Inlet)
(Opposed Connections)
345678
(Low Side Inlet)
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Chamber Type Discharge Silencers
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Part
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URBY, URDY
URDH
URDS
Weight
(Size)
Number
Min
Max
Min
Max
Min
Max
1
55-101-AA
4¹⁄₂
21
2
17
—
—
—
—
—
—
—
10
1¹⁄₂
55-115-AA
6¹⁄₂
24
2
20
—
—
—
—
—
—
—
15
2
55-102-AA
8
33
3
27
7
FIXED AT 6
—
—
—
—
20
See pages 1.1–1.3 for ordering information | www
2¹⁄₂
55-125-AA
10
34
3
28
8
FIXED AT 7
—
—
—
—
30
3
55-103-AA
10
46
3
40
8
FIXED AT 7
—
—
—
—
40
3¹⁄₂
55-135-AA
12
52
3
46
9
FIXED AT 8
—
—
—
—
55
4
55-104-AA* 14
53
3
47
10
6
22
—
—
8
16
70
5
55-105-AA* 16
65
3
59
11
6¹⁄₂
29
—
—
9
19
120
6
55-106-AA
18
72
3
66
12
8
32
—
—
10
22
160
8
55-108-AA
22
97
3¹⁄₂
90
14¹⁄₂
9
48
62
82
12
29
370
10
55-110-AA
26
122
3¹⁄₂
115
16¹⁄₂
11
63¹⁄₂
76¹⁄₂
106
14
40¹⁄₂
550
12
55-112-AA
30
135
3¹⁄₂
128
18¹⁄₂
12¹⁄₂
69
88
117¹⁄₂
15¹⁄₂
42
800
14
55-114-AA
36
161
3¹⁄₂
154
21¹⁄₂
14¹⁄₂
81
107
141
17¹⁄₂
49
1,250
16
55-116-AA
42
181
3¹⁄₂
174
24¹⁄₂
16¹⁄₂
92¹⁄₂
119¹⁄₂
158¹⁄₂
19¹⁄₂
55¹⁄₂
1,600
18
55-118-AA
48
188
3¹⁄₂
181
27¹⁄₂
18¹⁄₂
98
126¹⁄₂
164¹⁄₂
21¹⁄₂
56¹⁄₂
2,300
20
55-120-AA
48
202
4¹⁄₂
193
28¹⁄₂
19¹⁄₂
103
134
175¹⁄₂
22¹⁄₂
61
2,500
22
55-122-AA
54
204
4¹⁄₂
195
31¹⁄₂
21¹⁄₂
103
137
175¹⁄₂
24¹⁄₂
60
2,950
24
55-124-AA
54
239
4¹⁄₂
230
31¹⁄₂
22¹⁄₂
126
156¹⁄₂
210¹⁄₂
25¹⁄₂
76¹⁄₂
3,450
26
55-126-AA
60
259
4¹⁄₂
250
34¹⁄₂
25
132
175
228
27
78
4,400
28
55-128-AA
66
279
4¹⁄₂
270
37¹⁄₂
27
144
188
246
31
85
6,150
30
55-130-AA
72
304
4¹⁄₂
295
40¹⁄₂
29
161
203
272
32
96
7,250
Note: Dimensions and weights are nominal and may vary slightly with production models.
Request certified drawings of specific models for exact dimensions.
*Specify -TT for male pipe threaded units.
Typical Attenuation Curve
2.8
2.8
50
Attenuation, dB
40
Specifications
30
20
SD Group
10
Combination Chamber-
y Positive
0
Absorptive Type
63
125
250
500
1K
2K
4K
8K
Acoustical packing is suitable for 325˚F
Octave Band Center Frequency, Hz
Discharge Silencer
Blower Silencers Rotar
Blower Silencers
10
The SD Series Discharge Silencer is a
and larger are equipped with flanged
configuration. A low side inlet is designated
9
heavy-duty, all welded unit constructed of
connections drilled to 125/150 lb ANSI
the SDY Series; high side inlet, SDH Series;
carbon steel sheet and plate. It will provide
specifications. Smaller sizes are standard
and low opposed connection, SDS Series.
excellent pulse control and is equipped with
with male threaded pipe nipples. Units sized
The four types are fundamentally alike and
an acoustically-treated inlet for use on
4" and 5" are available in either flanged or
performance characteristics are identical.
critical PLV applications. Its pulse and noise
male pipe threads. Exterior surfaces receive
Mounting brackets and other options are
performance is recommended for all but the
a shop coat of rust-inhibitive primer and
available—see page 2.11.
most demanding applications, which may
may be finish painted in the field if desired.
require the RD Series on page 2.9. Sizes 4"
The SD Series is the basic end-in, end-out
SD Series
SDY Series
SDH Series
SDS Series
345678
(Low Side Inlet)
(High Side Inlet)
(Opposed Connection)
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Combination Chamber-Absorptive Type Discharge Silencers
Min
Max
Min Y Max
Min
Max
P
Part
K
D
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H
B
E
SDY
SDS
SDH
Weight
(Size)
Number
SDY
SDH
SDS
Min
Max
Min
Max
Min
Max
1
Sizes 1" and 1¹⁄₂" use URB Series (page 2.7)
1¹⁄₂
2
54-102-AA
8
28¹⁄₂
3
22¹⁄₂
8¹⁄₂
—
—
—
—
—
—
—
—
—
—
15
See pages 1.1–1.3 for ordering information | www
2¹⁄₂
54-125-AA
8
33
3
27
9
—
—
—
—
—
—
—
—
—
—
25
3
54-103-AA
8
39
3
33
10
—
—
—
—
—
—
—
—
—
—
30
3¹⁄₂
54-135-AA
10
39¹⁄₂
3
33¹⁄₂ 11
—
—
—
—
—
—
—
—
—
—
40
4
54-104-AA*
10
45
3
39
12¹⁄₂
14¹⁄₂
14¹⁄₂
8
2¹⁄₄
7¹⁄₂
16¹⁄₂
7¹⁄₂
9¹⁄₂
30¹⁄₂
32¹⁄₂
50
5
54-105-AA*
12
57¹⁄₂
3
51¹⁄₂ 15¹⁄₂ 17¹⁄₂
17¹⁄₂
9
2³⁄₄
9
23
9
12¹⁄₂
40
43¹⁄₂
80
6
54-106-AA
14
64
3
58
17
20
20
10
3¹⁄₄
9
25¹⁄₂ 10
15¹⁄₂
43¹⁄₂
49
110
8
54-108-AA
18
72
3¹⁄₂
65
21¹⁄₂ 26¹⁄₂
26¹⁄₂
12¹⁄₂
4
12
30¹⁄₂ 12
16¹⁄₂
49¹⁄₂
54
190
10
54-110-AA
22
85
3¹⁄₂
78
25¹⁄₂ 32¹⁄₂
32¹⁄₂
14¹⁄₂
5
13¹⁄₂
37
13¹⁄₂ 18
61¹⁄₂
65¹⁄₂
380
12
54-112-AA
26
98
3¹⁄₂
91
29¹⁄₂ 38
38
16¹⁄₂
6
15
44
15
24
69
77
550
14
54-114-AA
30
111
3¹⁄₂
104
30
40
40
18¹⁄₂
7¹⁄₂
16¹⁄₂
50
16¹⁄₂ 25
81
89¹⁄₂
800
16
58-116-AA
36
137
3¹⁄₂
130
35¹⁄₂ 47
47
21¹⁄₂
9¹⁄₂
18¹⁄₂
65
18¹⁄₂ 36
96
113¹⁄₂ 1,250
18
58-118-AA
42
150
3¹⁄₂
143
41
52
52
24¹⁄₂ 11¹⁄₂
20¹⁄₂
70¹⁄₂ 20¹⁄₂ 40¹⁄₂ 104¹⁄₂ 124¹⁄₂ 1,600
20
58-120-AA
42
176
4¹⁄₂
167
47
62
62
25¹⁄₂ 10¹⁄₂
21¹⁄₂
87¹⁄₂ 21¹⁄₂ 48¹⁄₂ 120¹⁄₂ 147¹⁄₂ 1,900
22
58-122-AA
48
195
4¹⁄₂
186
47
61
61
28¹⁄₂ 12¹⁄₂
23¹⁄₂
93¹⁄₂ 23¹⁄₂ 50¹⁄₂ 138¹⁄₂ 165¹⁄₂ 2,700
24
58-124-AA
48
213
4¹⁄₂
204
55¹⁄₂ 72
72
28¹⁄₂ 11¹⁄₂
24¹⁄₂ 110¹⁄₂ 24¹⁄₂ 60¹⁄₂ 146¹⁄₂ 182¹⁄₂ 3,000
26
58-126-AA
54
233
4¹⁄₂
224
55
76
76
31¹⁄₂ 13¹⁄₂
26
117
26
70
157¹⁄₂ 201¹⁄₂ 3,900
28
58-128-AA
54
250
4¹⁄₂
241
62
81
81
31¹⁄₂ 12¹⁄₂
28¹⁄₂ 126¹⁄₂ 28¹⁄₂ 71¹⁄₂ 173¹⁄₂ 216¹⁄₂ 4,400
30
58-130-AA
60
276
4¹⁄₂
267
68
90
90
34¹⁄₂ 14¹⁄₂
29¹⁄₂ 139
29¹⁄₂ 81
190
241¹⁄₂ 5,400
Note: Dimensions and weights are nominal and may vary slightly with production models.
Request certified drawings of specific models for exact dimensions.
*Specify -TT for male pipe threaded units.
2.9
Typical Attenuation Curve
50
Specifications
Attenuation, dB
40
RD Group
30
20
y Positive
Combination Chamber-
10
Absorptive Type
0
63
125
250
500
1K
2K
4K
8K
Rotar Blower Silencers Blower Silencers
Discharge Silencer
Octave Band Center Frequency, Hz
Acoustical packing is suitable for 325˚F
10
The RD Series Discharge Silencer is a heavy-
demanding installations. Sizes 4" and larger
if desired. The RD Series is the basic end-in,
9
duty, all welded unit constructed of carbon
are equipped with flanged connections drilled
end-out configuration. A low side inlet is
steel sheet and plate. It provides excellent
to 125/150 lb ANSI specifications. Smaller
designated the RDY Series; high side inlet,
pulse control and is equipped with an
sizes are standard with male threaded pipe
RDH Series; and low opposed connections,
acoustically treated inlet for use on critical
nipples. Units sized 4" and 5" are available in
RDS Series. The four types are fundamentally
PLV applications. Pulse control and noise
either flanged or male pipe threads. Exterior
alike and performance is identical. Mounting
attenuation provided by the RD Series is the
surfaces receive a shop coat of rust inhibitive
brackets and other options are available—
ultimate and is necessary for only the most
primer and may be finish painted in the field
see page 2.11.
RD Series
RDY Series
RDH Series
RDS Series
345678
(Low Side Inlet)
(High Side Inlet)
(Opposed Connection)
2
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Combination Chamber-Absorptive Type Discharge Silencers
Y
P
Part
K
D
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H
B
E
RDY
RDS
RDH
Weight
(Size)
Number
RDY
RDH
RDS
Min
Max
Min
Max
Min
Max
1
Sizes 1"–1¹⁄₂" use URB Series (page 2.7) or use U5 Series: (page 3.2)
1¹⁄₂
2
57-102-AA
8
33
3
27
9
—
—
—
—
FIXED AT 6
—
—
—
—
25
See pages 1.1–1.3 for ordering information | www
2¹⁄₂
57-125-AA
10
34
3
28
10
—
—
—
—
FIXED AT 7
—
—
—
—
35
3
57-103-AA
10
46
3
40
10
—
—
—
—
FIXED AT 7
—
—
—
—
40
3¹⁄₂
57-135-AA
12
52
3
46
11
—
—
—
—
FIXED AT 8
—
—
—
—
60
4
57-104-AA*
14
53
3
47
14¹⁄₂ 16
14¹⁄₂
10
4
8
20
8
14
33
39
80
5
57-105-AA*
16
65
3
59
16¹⁄₂ 18
16¹⁄₂
11
4¹⁄₂
9
26¹⁄₂
9
16¹⁄₂
43¹⁄₂
51
130
6
57-106-AA
18
72
3
66
20¹⁄₂ 22¹⁄₂
20¹⁄₂
12
5
10
30
10
20
46
56
160
8
57-108-AA
22
97
3¹⁄₂
90
24¹⁄₂ 28¹⁄₂
26
14¹⁄₂
6
12
45
12
26
65
79
410
10
57-110-AA
26
122
3¹⁄₂
115
28¹⁄₂ 34
32
16¹⁄₂
7
14
60¹⁄₂ 14
37¹⁄₂
79¹⁄₂ 103
600
12
57-112-AA
30
135
3¹⁄₂
128
35
42
39¹⁄₂
18¹⁄₂
8
15¹⁄₂
66
15¹⁄₂
39
91
114¹⁄₂
900
14
57-114-AA
36
161
3¹⁄₂
154
40¹⁄₂ 47¹⁄₂
45¹⁄₂
21¹⁄₂
10¹⁄₂
17¹⁄₂
78
17¹⁄₂
46
110
138
1,400
16
57-116-AA
42
181
3¹⁄₂
174
44¹⁄₂ 52¹⁄₂
50
24¹⁄₂
12¹⁄₂
19¹⁄₂
89¹⁄₂ 19¹⁄₂
52¹⁄₂ 122¹⁄₂ 155¹⁄₂ 1,800
18
57-118-AA
48
188
3¹⁄₂
181
47
54
52¹⁄₂
27¹⁄₂
14¹⁄₂
21¹⁄₂
95
21¹⁄₂
53¹⁄₂ 129¹⁄₂ 161¹⁄₂ 2,550
20
57-120-AA
48
202
4¹⁄₂
193
53¹⁄₂ 65
63¹⁄₂
28¹⁄₂
13¹⁄₂
22¹⁄₂ 100
22¹⁄₂
58
137
172¹⁄₂ 2,750
22
57-122-AA
54
204
4¹⁄₂
195
59¹⁄₂ 72
70
31¹⁄₂
15¹⁄₂
24¹⁄₂ 100
24¹⁄₂
57
40
172¹⁄₂ 3,300
24
57-124-AA
54
239
4¹⁄₂
230
66
81¹⁄₂
79¹⁄₂
31¹⁄₂
14¹⁄₂
25¹⁄₂ 123
25¹⁄₂
73¹⁄₂ 159¹⁄₂ 207¹⁄₂ 3,850
26
57-126-AA
60
259
4¹⁄₂
250
72
87
85
34¹⁄₂
16¹⁄₂
27
130
27
76
177
226
5,000
28
57-128-AA
66
279
4¹⁄₂
270
78
93¹⁄₂
91
37¹⁄₂
18¹⁄₂
31
140
31
81
192
242
6,950
30
57-130-AA
72
304
4¹⁄₂
295
78
95¹⁄₂
94
40¹⁄₂
20¹⁄₂
32
158
32
93
205
266
8,100
Note: Dimensions and weights are nominal and may vary slightly with production models.
Request certified drawings of specific models for exact dimensions.
*Specify -TT for male pipe threaded units.
Typical Attenuation Curve
2.10
2.10
50
Attenuation, dB
40
30
20
Specifications
10
y Positive
0
SURS Group
63
125
250
500
1K
2K
4K
8K
Octave Band Center Frequency, Hz
Chamber Type Multi-Use Silencer
Blower Silencers Rotar
Blower Silencers
10
9
SURS Series blower silencers are heavy-
the silencer units. The unit will provide
The SURS is a basic end-in, end-out
duty, all welded steel construction, suitable
excellent pulse control and is designed for
configuration. A low-side inlet model is
for application as either and inlet or
the most demanding applications.
designated as the SURSY Series; the
discharge silencer on rotary positive. These
Sizes smaller than four inches are equipped
SURSY is fundamentally identical to the
units are designed for blowers running
with standard male threaded pipe nipples,
SURS series in both dimension and
above critical transition speed, and
while the 4” and larger units have flanged
attenuation performance. Both series are
therefore, no acoustic packing material is
connections drilled to 125/150 lb ANSI
designed to operate at pressures to 15 psi.
included in the design. Instead, these units
specifications. As with other blower silencers,
Mounting brackets, shell lagging and other
have a specially designed, high-
the SURS Series employs a high-heat
accessories are available for both series of
performance, three chamber system which
aluminum paint system.
blower silencers.
345678
incorporates a diffuser on the blower side of
2
1
SURS Series
SURSY Series
(Low Side Inlet)
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See pages 1.1–1.3 for ordering information | www
Combination Chamber Type Multi-Use Discharge Silencers
SURS
SURSY
Y
P
D
L
N
H
Model
Part
Model
Part
K
Min.
Max
Weight
SURS-2
55-A02-SS
SURSY-2
55-B02-SS
2
12
40
3
34
9
4¹⁄₂
13
55
SURS-2.5
55-A25-SS
SURSY-2.5
55-B25-SS
2¹⁄₂
12
40
3
34
9
4¹⁄₂
13
55
SURS-3
55-A03-SS
SURSY-3
55-B03-SS
3
12
46
3
40
9
5
15
60
SURS-3.5
55-A35-SS
SURSY-3.5
55-B35-SS
2¹⁄₂
14
59
3
53
10
5¹⁄₂
20
90
SURS-4
55-A04-SS* SURSY-4
55-B04-SS †
4
14 †
59
3
53
10
6
20
100
SURS-5
55-A05-SS* SURSY-5
55-B05-SS †
5
16 †
71
3
65
11
7
25
160
SURS-6
55-A06-SS
SURSY-6
55-B06-SS
6
18
72
3
66
12
8
25
200
SURS-8
55-A08-SS
SURSY-8
55-B08-SS
8
26
111
3¹⁄₂
104
16¹⁄₂
10
41
520
SURS-10
55-A10-SS
SURSY-10
55-B10-SS
10
30
136
3¹⁄₂
129
18¹⁄₂
12
51
810
SURS-12
55-A12-SS
SURSY-12
55-B12-SS
12
36
138
3¹⁄₂
131
21¹⁄₂
14
50
1,130
SURS-14
55-A14-SS
SURSY-14
55-B14-SS
14
36
168
3¹⁄₂
161
21¹⁄₂
16
63
1,400
SURS-16
55-A16-SS
SURSY-16
55-B16-SS
16
42
181
3¹⁄₂
174
24¹⁄₂
18
51
1,800
SURS-18
55-A18-SS
SURSY-18
55-B18-SS
18
48
188
3¹⁄₂
181
27¹⁄₂
20
48
2,500
SURS-20
55-A20-SS
SURSY-20
55-B20-SS
20
48
214
4
205
28¹⁄₂
22
56
2,850
*Specify -TT for male pipe threaded units.
2.11
Accessories and
In addition to the standard accessories
Optional Features shown here, other special features such as
y Positive
special materials and finishes will be quoted
UCI, RIS, ICD IRB, IRD, SD, RD,
on request. Contact Universal Silencer with
Rotar Blower Silencers Blower Silencers
and SURS Blower Silencers
your specific requirements.
10
9
Mounting Brackets
Mounting Brackets or legs are available
for any of the silencers in this section.
Saddle type brackets for horizontal mount
and angle legs for vertical mount are
standard. See Spec. Sheet No. 1078.
Special design brackets will be quoted with
your specifications.
Horizontal
Vertical
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2
Pressure Vessel Construction
All silencers shown in this catalog may be
1
fabricated in accordance with Div. 1,
Section VIII—ASME Code for Unfired
Pressure Vessels. Dimensions are similar
to standard models, but material types and
thicknesses are selected to meet code
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requirements. Prices are quoted on
application to meet your pressure and
temperature conditions.
.universalsilencer
Inspection Openings
Oversize Flanges
Inspection Openings with bolted and
Frequently the blower flange size is larger
See pages 1.1–1.3 for ordering information | www
gasketed cover plates are available installed
than the required silencer’s connection.
at the time the silencer is fabricated. They
Rather than use a larger silencer, it is
are designed to withstand the usual range of
usually more economical to use an oversize
pressure encountered with blowers. One
reducing flange on the silencer. This is the
inspection opening is usually installed in
conventional piping practice and may be
each silencer chamber for cleaning or
used on either inlet or discharge silencers.
inspection. Standard sizes include:
Example: a 10" flange size silencer has
3"
4", 4"
6", 6"
8".
adequate capacity for a blower with a 12"
discharge flange. A flange having a drilling
pattern to match the 12" blower flange but
with a 10" bore to match the silencer nozzle
is substituted on the silencer inlet.
Two pipe sizes, (e.g. 10" to 14"), is the
recommended maximum variation. Prices
on request.
Typical Attenuation Curve
2.12
50
Attenuation, dB
40
30
20
10
CBF/CBFI Series
0
Compact Blower
63
125
250
500
1K
2K
4K
8K
Octave Band Center Frequency, Hz
Inlet Filter-Silencer
Blower Silencers
10
9
Filter and silencer combined in one unit.
The CBF and CBFI have the acoustic
capabilities of the Universal Silencer RIS
Series silencers and the filtration
performance of CC series filters.
CBF Series
Reduced cost, overall package size, weight,
(outdoor use)
CBFI Series (indoor use)
storage space, freight cost and damage.
WD
WD
Approximately one third the size of
¹⁄₈" NPT
¹⁄₈" NPT
Removable plate
pressure tap
pressure tap
for filter element access
conventional blower silencer, with the
Removable weatherhood
added benefit of excellent, high-efficiency
for filter element access
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filtration.
2
Reduced overall package noise without
L
P
P
L
D
D
further acoustic treatment.
1
H
H
Versatile—Suitable for inlet applications in
Y
Y
confined areas, outdoor or indoor, without
K
compromising acoustic or pressure drop
K
performance.
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.universalsilencer
Pressure Drop Curves
7
Element Part Number
70°F
P (nom.)
Paper
Felt
Wire
6
200°F
2
81-0471* 81-1203* 81-1036*
P
300°F
, inches of H
5
2¹⁄₂
81-0471* 81-1203* 81-1036*
4
3
81-1063
81-1205
81-1038
4
81-1063
81-1205
81-1038
3
5
81-0475
81-1207
81-1040
2 O
2
6
81-0475
81-1207
81-1040
See pages 1.1–1.3 for ordering information | www
8
81-1163
81-1209
81-1200
1
10
81-1163
81-1209
81-1200
0
12
81-1164
81-1210
81-1201
500
1K
1.5K
2K
2.5K
3K
3.5K
4K
4.5K
5K
5.5K
*Pair of elements required (stacked).
Velocity, ft/min
Models, Dimensions, Weights and Elements
CBF/CBFI
CBF
CBFI
P (nom.)
D
H
Y
K
CFM CAP
Part
WD
L
Weight
Part
B
L1
Weight
2
8
8
4
7
120
34-702-AA
10
13¹⁄₄
20
34-G02-AA
6¹⁄₂
12³⁄₄
20
2¹⁄₂
8
9
4³⁄₄
7
175
34-725-AA
10
14³⁄₄
25
34-G25-AA
6¹⁄₂
14¹⁄₄
25
3
12
10
5¹⁄₄
9
275
34-703-AA
16
17
50
34-G03-AA
10
16¹⁄₂
50
4
12
15
7¹⁄₂
9
500
34-704-AA
16
21¹⁄₄
60
34-G04-AA
10
20³⁄₄
60
5
16
17
8¹⁄₂
11
750
34-705-AA
20
26
85
34-G05-AA
12
25¹⁄₄
85
6
16
23
11¹⁄₂
11
1,100
34-706-AA
20
32
100
34-G06-AA
12
31¹⁄₄
100
8
24
24¹⁄₂
13³⁄₄
15¹⁄₂
2,200
34-708-AA
30
39
200
34-G08-AA
12
39¹⁄₄
185
10
30
35¹⁄₂
17³⁄₄
18¹⁄₂
3,000
34-710-AA
36
46¹⁄₂
305
34-G10-AA
18
45³⁄₄
295
12
34
39¹⁄₂
19³⁄₄
20¹⁄₂
4,300
34-712-AA
40
54¹⁄₂
385
34-G12-AA
24
53³⁄₄
370
Notes: 1. Non-ASME Code construction suitable for 15" Hg vacuum.
2. Weights are approximate and do no include the weight of the filter element.
2.13
This extremely compact blower silencer
operable in conditions up to 15 psig.
works as either an inlet or discharge
Flanged or threaded connections are
silencer on rotary positive blowers. It is
available. Exterior surfaces receive a shop
about one-third the size of a standard
coat of rust inhibitive primer.
silencer, and reduces overall package size,
CB Series
cost, weight and storage space. The unit’s
internal pack material is suitable for
Blower Silencers
Compact Blower Silencer
temperatures up to 325 degrees. The unit is
10
9
K
P
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2
D
1
L
H
P
Y
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.universalsilencer
Pressure Drop Curves
7
70°F
6
200°F
P
Typical Attenuation Curve
300°F
, inches of H
5
50
4
Attenuation, dB
40
3
See pages 1.1–1.3 for ordering information | www
30
2 O
2
20
1
10
0
0
63
125
250
500
1K
2K
4K
8K
500
1K
1.5K
2K
2.5K
3K
3.5K
4K
4.5K
5K
5.5K
Octave Band Center Frequency, Hz
Velocity, ft/min
Compact Blower Silencers
Model
Part Number
P (nom.)
D
L
H
Y
K
Weight
CFM CAP
CB-2
56-702-AA
2
8
11
8
4
7
15
120
CB-2¹⁄₂
56-725-AA
2¹⁄₂
8
12¹⁄₂
9¹⁄₂
4³⁄₄
7
25
187
CB-3
56-703-AA
3
12
13¹⁄₂
10¹⁄₂
5¹⁄₄
9
35
270
CB-4
56-704-AA
4
12
18
15
7¹⁄₂
9
45
480
CB-5
56-705-AA
5
16
20
17
8¹⁄₂
11
70
750
CB-6
56-706-AA
6
16
26
23
11¹⁄₂
11
85
1,080
CB-8
56-708-AA
8
24
31
27¹⁄₂
13³⁄₄
15¹⁄₂
170
1,920
CB-10
56-710-AA
10
30
39
35¹⁄₂
17³⁄₄
18¹⁄₂
275
3,000
CB-12
56-712-AA
12
34
43
39¹⁄₂
19³⁄₄
20¹⁄₂
355
4,320
2.14
These wide base plate products
base plate is only the basic plate and the
accommodate a variety of blower package
URBY discharge silencer. Please see page
UNI-BASE
designs. The UNI-BASE package and the
2.7 for performance and sizing information
USI-BASE base plate use the same basic
for the URBY series silencers, page 2.15 for
Ultra-Wide Base
base plate and discharge silencer. The UNI-
information on the URBN series silencers,
BASE package includes the Universal
and page 8.9 for performance data, weights
Plates/Components
Silencer model URBN high-side inlet silencer
and dimensions of CCF filters.
and CCF inlet air filter, while the UNI-BASE
Rotary Positive Blowers
Blower Silencers
10
UNI-BASE Package
9
CCF (see page 8.9)
URBN (see page 2.15)
345678
2
1
URBY (see page 2.7)
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.universalsilencer
UNI-BASE Base Plate Only
URBY (see page 2.7)
See pages 1.1–1.3 for ordering information | www
UNI-BASE Base Plates/Components Part Numbers
Size
UNI-BASE Package
Base Plate Only
URBN Only
URBY Only
CCF Only
2"
80-1873
55-202-ABP
55-502-AA
55-202-AA
34-L02-TT*
2¹⁄₂"
80-1874
55-225-ABP
55-525-AA
55-225-AA
34-L25-TT*
3"
80-1875
55-203-ABP
55-503-AA
55-203-AA
34-L03-TT*
4"
80-1876
55-204-ABP
55-504-AA
55-204-AA
34-L04-TT*
5"
80-1877
55-205-ABP
55-505-AA
55-205-AA
34-L05-TT*
6"
80-1878
55-206-ABP
55-506-AA
55-206-AA
34-L06-TT*
2.15
UNI-BASE
Ultra-Wide Base
Plates/Components
Blower Silencers
Rotary Positive Blowers
10
9
Dimensions and Weights
UNI-BASE Base Plate (w/URBY)
Approx.
P (nom.)
A
B
C
CD
D2
E
FS
G
H2
J
K2
L
Q (Dia.)
S
Y
Weight
2
39
1¹⁄₂
20³⁄₄
10.56
8
6.31
13
23.38
16
5
7
30
3¹⁄₂
21
6
125
2¹⁄₂
44¹⁄₂
¹⁄₂
20.88
11.13
10
6.56
14¹⁄₄
27.38
17
6
8
31
4
25
7
170
3
55¹⁄₂
4
31¹⁄₂
12.00
10
7¹⁄₂
15.13
29³⁄₄
17
6
8
43
4³⁄₄
26¹⁄₄
7
270
4
56
—
37.31
15.38
14
7.88
16.44
33
24¹⁄₂
8
10
50
6
29³⁄₄
11
355
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5
66
—
43.38
18¹⁄₄
16
13³⁄₄
14³⁄₄
35
23¹⁄₂
9
11
62¹⁄₂
11
30¹⁄₂
12
500
6
66
—
52
18¹⁄₄
18
10.38
15.13
35¹⁄₄
26¹⁄₂
10¹⁄₄
12
69
12
30¹⁄₂
12
645
2
Notes: 1. Sizes 2"–3" URBY discharge silencers are shipped standard with male pipe threaded connections. 4" and 5" URBY discharge silencers are shipped standard with male
pipe threaded discharge connections and plain pipe blower connections. 6" URBY discharge silencers are shipped standard with flanged discharge connection drilled
1
to 125/152 lb. ANSI specifications and plain pipe blower connections.
2. Sizes 2"–3" URBY discharge silencers have a 2" NPT relief valve coupling and plug. Sizes 4"–6" URBY discharge silencers have a 3" NPT relief valve coupling and plug.
3. UNI-BASE base plate kit sizes 2"–4" require gussets.
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URBN Silencers
P1/P2 (nom.)
D1
H1
K1
Y1
Y2
Approx. Weight
2
8
27
7
6
3¹⁄₂
25
2¹⁄₂
10
28
8
7
4¹⁄₂
35
.universalsilencer
3
10
40
8
7
4¹⁄₂
50
4
14
47
10
6
5¹⁄₂
80
5
16
60
11
6
6¹⁄₂
140
6
18
66
12
8
7¹⁄₂
170
Notes: 1. Sizes 2"–4" URBN inlet silencers are shipped with male pipe threaded inlets and plain pipe outlets. Sizes 5" and 6" URBN inlet silencers are shipped standard with
flanged inlet connections drilled to 125/150 lb ANSI specifications and plain pipe outlets.
CCF Silencers (please see page 8.9)
See pages 1.1–1.3 for ordering information | www
