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BLD non-return damper
BLD non-return damper

BLD – Non-return damper

Halton BLD non-return dampers are used in offshore and marine applications to prevent backflow through ventilation ductwork.

Overview

  • Fixed frame in painted, galvanized or stainless steel. Blades of galvanized or stainless steel.
  • Models for horizontal or vertical installation
  • Available as ATEX certified
  • Leakage class (EN1751:2014) of closed damper up to class 2. Details available from Halton.
  • Blades contain silicone seal to lower the leakage through blades
  • Blades linked and open in parallel
  • Adjustable by changing the position of counterweights. Standard construction places weights on the right hand side, weights on the left hand side available as an option.
  • Maximum duct pressure for damper construction 5000 Pa and maximum air velocity 15 m/s. In case of high duct pressure, contact Halton Marine for finding the most suitable solution
  • Temperature operation range up to +100°C, optionally up to +180°C

Specification

Halton BLD non-return dampers are used in offshore and marine applications to prevent backflow through ventilation ductwork system. The BLD dampers do not need an actuator or motor. Non-return dampers can be installed in rectangular or circular ducts, horizontally or vertically. If required, they can easily be set by adjusting the weight of each damper/installation. When the blades are in the open position, the device does not cause significant pressure loss, noise or flow disturbance.

Dimensions and Material Thickness

BLD non-return dampers meet international standards for both rectangular (width B 150-1200 mm and height H 150-1400 mm, 1mm division) and circular ducts (Ø100 – 1250 mm). Non-standard dimensions are available on request. Standard flange width 27 mm. Flanges and drilling also available according to ISO 15138 standards. Modular construction sizes up to 2400×2800 mm.  Standard frame material thickness 3 mm. Blades made of two sheets, each being 0.8 mm thick (sandwich design).

BLD, general drawing

BLD drawing, circular connections

BLD circular, with connection flanges

Material and Finishing

PART MATERIAL FINISHING
Frame Carbon steel Painted or galvanised
Frame Stainless steel EN 1.4301 (AISI304), EN 1.4404 (AISI316L), EN 1.4432 (AISI316L)  –
Blades Steel Galvanised
Blades Stainless steel EN 1.4301 (AISI304), EN 1.4404 (AISI316L), EN 1.4432 (AISI316L)  –
Maintenance-free bearings Stainless steel EN 1.4404 (AISI316L) / Option: bronze bearings available  –
Shafts Stainless steel EN 1.4404 (AISI316L)  –

Standard frame material thickness 3 mm.

Blades are made of two sheets, each of being 0.8 mm thick.

Product Models and Accessories

  • Models for horizontal and vertical installation available
  • Circular connection pieces are available.
  • Standard construction places weights on the right hand side. Weights on the left hand side available as an option.

Operation Principles

Non-return damper will allow one-way airflow in the ductwork. This feature is based on imbalanced blades. When the pressure in the ductwork drops below minimum opening force required, the blades close and seal the duct to prevent backflow. The minimum opening force can be adjusted with weights. Minimum opening pressure 30 Pa.

Weights

Weights of standard BLD dampers (kg). Frame thickness 3 mm.

H/HEIGHT
(mm)
 B / WIDTH (mm)
150 200 300 400 500 600 700 800 900 1000 1100 1200
150 8 9 11 13 15 16 18 20 22 24 25 27
200 10 12 12 14 16 19 20 22 24 26 28 29
300 12 13 15 18 20 21 24 26 29 31 34 35
400 14 15 18 20 23 25 28 30 33 36 37 40
500 17 17 21 24 27 29 32 35 37 40 43 45
600 19 20 24 26 29 32 36 39 42 45 47 51
700 21 23 26 30 33 37 40 43 47 50 53 57
800 22 24 27 33 36 40 43 47 51 54 58 62
900 26 28 32 36 39 44 48 52 56 60 63 67
1000 28 30 34 39 43 48 51 55 60 64 68 72
1100 31 33 38 42 47 51 56 60 65 70 72 78
1200 33 35 40 45 50 54 59 64 69 74 78 84
1300 36 38 44 48 53 58 64 69 74 79 83 89
1400 38 40 46 51 56 62 67 73 78 83 88 94
D2 ØD WEIGHT
mm kg
100 12
160 12
200 15
250 17
315 21
400 26
500 36
630 45
800 63
1000 87
1250 116

Weights stated above include counter weights.

Installation

Installation and maintenance instructions are with each non-return damper delivery. Copies of Operation and Maintenance manuals are available from Halton Marine Sales offices and distributors.

Product Code

(S)=Shape of Connection
(A) Circular (D1)
(B) Circular (D1) outlet
(C) Circular (D2)
(R) Rectangular

(W)=Width
Min=150 mm
Max=1200 mm

(H)=Height
Min=150 mm
Max=1400 mm

(D)=Diameter
Min=100 mm
Max=1250 mm

(SF)=Flange Option
(H0) Connection flange in circular connections
(H1) Connection + loose flange in circular connections
(HA) Flanges (2 sides)
(HB) Counter flanges (2 sides)
(HC) Counter flange (1 side)
(N0) (N0) ISO 15138 flange drilling CO+CIR
(N1) ISO 15138 flange drilling CO+LO+CIR
(NA) Not Assigned (circular connection)
(NR) ISO 15138 flange drilling

(DF)=Deep Frame Model
(N) No
(Y) Yes

(LM)=Left Hand Model
(N) No
(Y) Yes

(CW)=Counter Weights Included
(Y) Yes

(MA)=Material Blades
(AS) Stainless steel 0.8 mm EN1.4404
(CS) Carbon steel 0.75 mm
(LS) Stainless steel 0.8 mm EN1.4432
(SS) Stainless steel 0.8 mm EN1.4301

(FM)=Frame Material
(A3) Stainless steel 3 mm EN1.4404
(C3) Carbon steel 3 mm EN1.4404
(L3) Stainless steel 3 mm EN1.4432
(S3) Stainless steel 3 mm EN1.4301

(FI)=Finishing
(HG) Hot galvanized
(NA) Not Assigned (acid treatment)
(PN) Painting

(BM)=Bearing Material
(BR) Bronze
(AS) Stainless steel EN1.4404

Code example
BLD/R-1000-1000,SF=HA,DF=N,LM=N,CW=Y,MA=CS,FM=C3,FI=HG,BM=AS,ZT=N

Downloads

BLD – Non-return damper
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BLD – Non-return damper
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BLD – Non-return damper
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BLD 单向阀
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