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FIBERGLASS ROUND DAMPERS AND BACKDRAFT DAMPERS

 

Belco Fiberglass Dampers are manufactured to meet the needs of the air handling industry by providing a corrosion-resistant FRP Damper that is used to regulate a gas flow or shut off and isolate a system. The operating conditions for the dampers are designed to match the operating conditions of the duct system. Premium vinyl ester resins are used throughout the damper. Fire-retardant resins are also available for a Class I flame spread.
 

BELCO MANUFACTURING CO. provides five damper models.

MODEL 201 dampers are used to control airflow for balancing a system. This model is less expensive and has a shaft seal, but does not have a blade seal.

MODEL 202 dampers are used to control airflow for balancing a system. This model has a shaft seal and full circumferential blade stop.

 

 

MODEL 203 (AMCA Licensed) dampers are used for isolating a system with low leakage. This model has a shaft seal, blade seal, and a full circumferential blade stop. Model 203 dampers are designed for up to 30” wc with an AMCA certified leakage rate of 5.2 cfm/ft2.

MODEL 204 are used for isolating a system, and has a PTFE encapsulated O-ring to provide a bubble-tight seal. This seal is mechanically fastened to allow easy replacement.
BACKDRAFT DAMPERS are designed to prevent air from flowing back into the system when the fan is turned off. These may sometimes be referred to as check valves.

CONSTRUCTION:  Bearings are mounted “outboard” to the damper body & contained in a plastic sleeve. The bearing is Teflon and the seal is an appropriate elastomer for the chemical service. All is contained within this sleeve with a retaining nut. The blade is a heavy fiberglass disk.  Care is taken to produce the highest quality damper and tooling is used to manufacture reproducible and consistent parts. The damper body is a one piece construction, hand fabricated on a polished steel mold.

Dampers can be made with a variety of resins, cure systems, gasket materials, shaft materials, internal hardware, external hardware, coatings, flange patterns, actuators, and face to face lengths.  This brochure includes our standard construction materials.  Contact Belco Manufacturing for other available options.

 

MODEL 203 DAMPER (AMCA LICENSED) - STANDARD CONSTRUCTION
 


SUGGESTED SPECIFICATIONS FOR ROUND FRP DAMPERS
 
Furnish and install at locations shown on plans, round FRP single-blade fiberglass dampers. Damper frame shall be of one piece construction with a resin rich interior corrosion barrier minimum of 100 mils. A structural lay-up shall consist of alternate layers of chopped strand mat and woven roving to conform to ASME/ANSI RTP-1 and PS15-69. The glass to resin ratio shall be a minimum of 35% glass to 65% resin. Wall thickness, flange thickness, drilling pattern and width shall conform to PS15-69. Exterior surface of the damper shall contain UV inhibitors and a gel-coat, color to match duct system.

The damper blade shall be constructed of the same material as the damper frame and shall have a resin rich surfacing veil on both sides. Blade stiffeners shall be FRP or FRP encapsulated as required for stiffness.
The axle shall be pultruded fiberglass or 316 stainless steel, as required to meet corrosion resistance requirements. Leakage shall not exceed 3 cfm per square foot at 12” wc or 5.25 cfm per square foot at 30” wc as required in this specification for isolation. Damper shall be provided with stainless steel hand locking quadrant, gear operators, chain wheel operators, or other actuation devices as required in this specification. All interior metal shall be 316 stainless steel. Gaskets shall be EPDM. Other gasket materials shall be available upon request.

All FRP fabrication shall meet or exceed quality requirements of PS15-69 and ASME/ANSI RTP-1. Damper shall be Belco Mfg. Models 201, 202, 203, or 204.


CUSTOM CONFIGURATIONS:  Belco dampers can be furnished in a variety of custom configurations including: extended length between flanges, undrilled flanges, inline dampers, and either built into a section of duct or plain-end for field joint by installers. Damper Models 201, 202, and Backdraft Dampers, can be furnished in rectangular configurations using our custom fabrications.

 

BELCO DAMPERS & BACKDRAFT DAMPERS
 

STANDARD CONSTRUCTION

Frame:  Vinyl Ester FRP

Blade:  Vinyl Ester FRP

Axle:  Vinyl Ester FRP or 316 SS

Bearings:  Teflon

Sizes:   See table below

Internal Hardware:  316 SS

Max Operating Temperature:  200°F

Max System Pressure:  30” wc

Resin System:  Fire Retardant Vinyl Ester with MEKP Cure System

Connections:  NBS PS 1569 Table 2 for Standard Ductwork

External Coating:  Gel Cost with UV Inhibitors (White, Gray, or Tan)

Gasket:  EPDM

Face to Face:  12" up to 48" size

  

Actuator:  Locking Quadrant Hand Level through 20" Diameter, Aluminum Worm Gear for larger than 20".  (Electronic, Pneumatic, and Chain-Wheel Operators are available)

Options:  Dampers can be made with a variety of resins, cure systems, gasket materials, shaft materials, internal hardware, external hardware, coatings, flange patterns, actuators, and face to face lengths.  Contact Belco Manufacturing for other available options.

 
     
 

Standard Sizes

Flange Thickness

Flange Diameter O.D.

Bolt Circle Diameter

Bolt Hole Diameter

Number of Bolt holes

Blade Edge Thickness

Axle Diameter

6"

1/4"

10 3/8"

9"

7/16"

8

3/8"

3/4"

8"

1/4"

12 3/8"

11"

7/16"

8

3/8"

3/4"

10"

3/8"

14 3/8"

13"

7/16"

12

3/8"

3/4"

12"

3/8"

16 3/8"

15"

7/16"

12

3/8"

3/4"

14"

3/8"

18 3/8"

17"

7/16"

12

3/8"

3/4"

16"

1/2"

20 3/8"

19"

7/16"

16

3/8"

1 1/4"

18"

1/2"

22 3/8"

21"

7/16"

16

3/8"

1 1/4"

20"

1/2"

24 3/8"

23"

7/16"

20

1/2"

1 1/4"

24"

1/2"

28 3/8"

27"

7/16"

20

1/2"

1 1/4"

30"

1/2"

34 3/8"

33"

7/16"

28

1/2"

1 1/4"

36"

1/2"

40 3/8"

39"

7/16"

32

1/2"

2"

42"

5/8"

46 3/8"

45"

7/16"

36

3/4"

2"

48"

5/8"

54 3/8"

52"

9/16"

44

3/4"

2"

54"

5/8"

60 3/8"

58"

9/16"

44

3/4"

2"

60"

5/8"

66 3/8"

64"

9/16"

62

3/4"

2"

72"

5/8"

78 3/8"

76"

9/16"

60

3/4"

2"
 

 

CERTIFIED RATINGS AUTHORIZED BY AMCA
 

Belco Manufacturing Company, Inc. certifies that the Standard Model 203 Dampers shown herein are licensed to bear the AMCA Seal. The ratings shown are based on tests and procedures performed in accordance with AMCA Publication 511 and comply with the requirements of the AMCA Certified Ratings Program. The AMCA Certified Ratings Seal applies to air leakage and air performance ratings only.

1) Test method per AMCA Standard 500-89
2) Torque: 1049 in-lb for 48” damper, 67.35 in-lb for 6” damper
3) Air leakage is based on operation between 50°F & 104°F

 

Damper Diameter Model 203
Round Dampers
AMCA Leakage Class
1"wg, 4"wg, 8"wg, 12"wg
6" - 48" Class 1
Tested Leakage Rates are Avaliable
Contact Belco Manufacturing

Pressure/Class

 Leakage, L/s/m2 (ft3/min/ft2)
Required Rating Extended Range
(Optional)
0.25 kPa
(1" wg)		 1.0 kPa
(4" wg)		 2.0 lPa
(8" wg)		 3.0 kPa
(12" wg)
1A 15.2 (3) 40.6 (8) 55.9 (11) 71.1 (14)
1 20.3 (4) 40.6 (8) 55.9 (11) 71.1 (14)
2 50.8 (10) 102 (20) 142 (28) 178 (35)
3 203 (40) 406 (80) 569 (112) 711 (140)
   
 

 

 

BELCO BACKDRAFT DAMPERS
 
HORIZONTAL BACKDRAFT DAMPERS
 

 
 
VERTICAL BACKDRAFT DAMPERS
 

 

 
 

DAMPER NAMES

Dampers are often referred to by many different industry names.
The following chart may be used as a guide to determine the damper model required.
 
INDUSTRY NAME BELCO EQUIVALENT (Model)
Check Valves Backdraft
Control Dampers 201, 202
Volume Dampers 201, 202
Butterfly Dampers 201, 202, 203, 204
Shut-Off Valves 203, 204
Isolation Valves 203, 204
Zero-Leak Dampers 204—Bubble Tight
 

 

DOWNLOADS
 
 
 

WARRANTY
 
BELCO FIBERGLASS DAMPERS are warranted for (18) months from the date of shipment to be free from defects in manufacturing, materials, or workmanship. Liability shall not exceed the purchase price of the damper and is limited to repair or replacement. BELCO MANUFACTURING CO. shall not be liable for any costs incurred either directly or indirectly other than repair or replacement of the product.
 
 
 

 Belco Manufacturing Co. Inc.
P.O. Box 210 • Belton TX 76513-0210
(254) 933-9000 • FAX (254) 939-2644
1-800-251-8265

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