Heavy Duty Back Blast Damper

3/16" FULLY Welded Steel Construction - These units are 'tanks' and built to withstand a sudden burst of pressure. Most installations require additional support structures or special hanging.

Size Price
4" $1,531
5" $1,665
6" $1,799
7" $1,930
8" $1,998
9" $2,062
10" $2,197
11" $2,265
12" $2,329
13" $2,395
14" $2,528
15" $2,663
16" $2,729
17" $2,794
18" $2,996
19" $3,062
20" $3,128
22" $3,260
23" $3,408
24" $3,556
25" $3,704
26" $3,852
27" $4,001
28" $4,149
29" $4,297
30" $4,445
K&B Duct Back Blast K&B Duct Back Blast



















Optional Relief Doors and/or Directional Venting Available

Available in sizes 4" to 30"



10 GA. Counter Balanced Inlet Flap/Door

  • The entry duct is angled and extends into the unit. At rest or during an explosion, the door lays tightly against the incoming duct, stopping air flow from the collector to the duct.
  • Adjustable counter balancing arms give the HD inlet door an effective weight of approximately one pound enabling the door to open easily and thereby minimize static pressure losses.
  • The flap shaft freely operates on sealed bearings with grease fittings.

Fast and Sure Passive Action

  • Two things insure that the door will act quickly with the reversed air wave.
    • Stops keep the door at a 15 degrees to the air stream
    • The outlet is offset to the inlet so that any reversed air or pressure is assured of catching the door and slamming it shut.