Access Doors
METU-SYSTEM Catalog 6b
58
Access Door General Characteristics
61
RD Access Doors
64
GX Access Doors
67
LX Access Doors
70
RRD Access Doors for Round Ducts
74
IRD Insulated Access Doors for Rectangular Ducts
77
Special: IRD-3PL Insulated Access Doors for Rectangular Ducts
78
Special: IRD-3DE Insulated Access Doors for Rectangular Ducts
79
Special: IRD-DW1 Insulated Access Doors for Rectangular Ducts
80
Special: IRD-DW2 Insulated Access Doors for Rectangular Ducts
81
Special: IRRD-3PL Insulated Access Doors for Round Ducts
82
Special: IRRD-3DE Insulated Access Doors for Round Ducts
83
Special: IRRD-DW1 Insulated Access Doors for Round Ducts
84
Special: IRRD-DW2 Insulated Access Doors for Round Ducts
85
Special Access Doors Questionnaire
57
Access Doors General Characteristics
Overview
Our standard access doors have a few common characteristics which have been gathered in this section
to avoid unnecessary redundancies.
Should you not be able to find the specific access door corresponding to your needs,
please do not hesitate to contact us. Chances are that we might be able to find an adequate solution.
Air Tightness
Outdoor Exposure
The “TÜV NORD” certificate confirms that the air-tightness
of the METU RD and GX access doors is far lower than
the admissible leakage of the highest tightness class D
according to DIN EN 1507, assuming the Access Doors
have been properly installed according to our instructions.
It is especially important that:
- the knobs are sufficiently tightened (F > 500 N)
- the access doors are installed on smooth and clean
surfaces
Should the access doors be installed outside the building,
the following points should be taken into consideration:
- Install the access doors in the least exposed areas.
- Install the access doors in areas where rain water
cannot accumulate (not on top of rectangular ducts
for example).
- The knobs made of POM will not corrode, but may
discolor and become brittle over time. Metal knobs are
therefore recommended, although the risk of corrosion
is more important.
- Make sure you choose the appropriate gasket, such as
the self-adhesive rubber edge molding (SKK) which has
higher UV and ozone resistances.
- Finally, galvanized access doors can also be ordered
with a thicker zinc coating (275 g/m2) upon request.
Minimum order quantities and longer lead times must
be expected.
Versions in Stainless Steel V4A
The access door cover plates are made of
stainless steel V4A (1.4571, or ASTM 316Ti).
The bolts, springs, nuts and eventual metal knobs
are made of stainless steel V2A (1.4301, ASTM 304).
Versions in Aluminum
The access door cover plates are made of aluminum.
The bolts, springs, nuts and eventual metal knobs are
made of stainless steel V2A (1.4301, ASTM 304).
Liquid Tightness
Versions with Rubber Edge Molding (SKK)
Standard access doors fitted with a polyethylene (PE)
gasket have a limited liquid tightness (they are considered
splash-tight).
The rubber edge molding is wrapped along the
opening and brings the following advantages:
Superior liquid tightness can be achieved using access
doors fitted with a rubber edge molding (SKK), assuming
it has been cut and installed properly (please refer to the
Original Löwe 3101 scissors, Art. No. G04V-1005).
It protects against injuries (usually cuts) or damage
to the cleaning equipment.
It provides better tightness properties as smaller
irregularities along the opening are covered.
Special Versions
Liquid and even oil-tightness can be achieved with
the GX access doors fitted with NBR gaskets.
Pre-requisites to the above are the absence of joints
and/or seams crossing the access door opening and an
installation in accordance with our instructions. The GX
access doors are only available for rectangular ducts.
We are usually able to propose special access door
versions fulfilling your specific requirements.
Safety / Retaining Cable
Equipotential Bonding
For additional security
(DIN EN 12097, 2006, 4.2.2)
a retaining cable
(Art. No. D01V-2001)
can be fitted on practically all
access doors.
Should an equipotential bonding be required, we
recommend the use of access doors fitted with a retaining
cable and metal knobs, as these allow a metal-to-metal
contact between all access door parts and the duct.
58
In view of the numerous execution possibilities, we
recommend you first order one piece in order to test it,
as special product versions can neither be returned
nor refunded.
METU-SYSTEM Catalog 6b
Access Doors General Characteristics
Installation Clearances
Maximum Duct Wall Thickness
The following clearances must be observed on rectangular
ducts:
For standard access doors with polyethylene, ceramic
wool or silicon gaskets, the maximum duct wall
thickness is 5 mm.
B
A
B
C
D
A
C
=
=
=
=
min.
min.
min.
min.
50
50
15
15
mm
mm
mm
mm
D
There are no such limitations with circular ducts, as the
range of access doors has been determined in such a way
that opening size and duct diameter combination will not
weaken the circular duct unduly.
Creating the Opening Beforehand
For thicker duct wall thickness special access door
versions (with longer bolts) must be ordered.
Access doors with rubber edge molding (SKK) can be
installed on duct walls having a maximum thickness
of 2 mm.
Air-flow Resistances
The METU access doors can be divided, as far as the
resistances to the airflow are concerned, into three
groups:
1. RD and RRD Access Doors (Standard)
The opening is normally made using the self-adhesive
template coming with the access door. The following
dimensions can be used to create the opening
without the template:
B
All figures in mm
Type
2. Access Doors with a 3rd Cover (3PL)
R
H
Opening
B
H
R
RD 18
(180 × 80 mm)
180
80
40
RD 21
(200 × 100 mm)
200
100
50
RD 315
(300 × 150 mm)
300
150
75
RD 32
(300 × 200 mm)
300
200
100
RD 42
(400 × 200 mm)
400
200
100
RD 43
(400 × 300 mm)
400
300
150
RD 53
(500 × 300 mm)
500
300
150
RD 54
(500 × 400 mm)
500
400
200
RD 64
(600 × 400 mm)
600
400
200
RD 65
(600 × 500 mm)
600
500
250
RD 75
(700 × 500 mm)
700
500
250
3. GX and LX Access Doors
Due to friction, the air-flow velocity near the duct wall
is practically nil.
The results of our air-flow resistance tests are the
following:
These dimensions are also valid for the GX and LX access
door templates.
- All three groups have relatively low air-flow
resistance values which roughly correspond an
additional ductwork length of 200 to 400 mm.
Type
Opening
B
H
R
- The differences between the three groups are small.
RRD 18
(180 × 75 mm)
182
76
38
RRD 21
(200 × 97 mm)
200
97
48,5
RRD 32
(300 × 195 mm)
298
194
97
- The access doors with a 3rd cover (3PL) show the
lowest air-flow resistances, followed by the RD and
RRD standard access doors.
RRD 43
(400 × 290 mm)
400
290
145
RRD 54
(500 × 390 mm)
496
390
195
The RRD opening dimensions refer to the template when
lying on a flat surface.
We do not recommend creating the opening beforehand
when special access door versions have been ordered.
METU-SYSTEM Catalog 6b
- The GX and LX access doors offer the highest
resistances, as their bulging inner-surfaces enter
deeper into the air-flow. At the same time they offer
better aerodynamic characteristics which reduce
turbulences as well as the deposit and accumulation
of dust and dirt.
59
Access Doors General Characteristics
Standard Knobs
Knob Torques
The ergonomic design of our knobs allows a comfortable
handling and an accrued clamping power.
Attempt to quantify the maximum clamping force of the
access door knobs:
Safety is also taken into consideration as they prevent
the bolts from protruding.
The corrosion resistant material of the POM knobs
guarantee years of trouble-free operation.
Detailed material specifications can be found
in the Additional Information ZI-301.
Type
Knob
RD 18 (180 × 80 mm)
RD 21 (200 × 100 mm)
M8
M8
RD 315 (300 × 150 mm)
RD 32 (300 × 200 mm)
RD 42 (400 × 200 mm)
RD 43 (400 × 300 mm)
RD 53 (500 × 300 mm)
M10
M10
M10
M10
M10
RD 54 RD 64 RD 65 RD 75 M12
M12
M12
M12
The above information are also valid for the
other access door types.
Metal Knobs
1.000 - 1.500 N
1.200 - 1.700 N
2.000 - 3.000 N
Clearance between the duct wall and the upper edge of
the knob or lever in closed position:
RD Access Door
RD
RD
RD
RD
RD
RD
RD
RD
RD
RD
RD
18 ≈
21 ≈
315≈
32 ≈
42 ≈
43 ≈
53 ≈
54 ≈
64 ≈
65 ≈
75 ≈
37
35
50
50
50
56
56
67
67
73
73
mm
mm
mm
mm
mm
mm
mm
mm
mm
mm
mm
GX Access Door
Are commonly used:
-
-
-
-
-
M8 Knob Applicable Torque
M10 Knob Applicable Torque
M12 Knob Applicable Torque
Daylights / Clearances
Opening
(500 × 400 mm)
(600 × 400 mm)
(600 × 500 mm)
(700 × 500 mm)
After tightening the knobs as much as possible manually,
the torque is read on a dynamometric wrench:
with higher operating temperatures,
when installed outside buildings,
when specific chemical resistances are required,
with some special insulated access doors with a
thinner insulation,
with some access doors fitted with a lock.
GX 21 ≈ 20 mm
GX 32 ≈ 20 mm
GX 43 ≈ 15 mm
LX Access Door
LX 32 ≈ 20 mm
LX 43 ≈ 15 mm
RRD Access Door
Access Door Material
Knob Material
Galvanized Steel
Stainless Steel V2A
Stainless Steel V4A
Aluminum
Galvanized Steel
Stainless Steel V2A
Stainless Steel V2A
Stainless Steel V2A
60
RRD
RRD
RRD
RRD
RRD
18≈ 36 mm
21 ≈ 40 mm
32≈ 55 mm
43≈ 60 mm
54≈ 70 mm
Metal knobs have usually the same clearances, since the
same bolt length is required for opening or closing the
access door.
METU-SYSTEM Catalog 6b
Access Doors RD
• For rectangular ducts
• Eleven (11) opening sizes!
• In galvanized steel (150 and 275
upon request), stainless steel
(304 and 316Ti) and aluminum
depending on the types and
dimensions.
• The thin and sometimes wavy duct-wall is clamped between two stable covers
• Two knobs allow a comfortable
handling and operation of the
access door.
Locking nuts prevent
the knobs from being
totally removed
Press formed, strong and attractive in
appearance, the covers are available
in galvanized steel, stainless steel
and aluminum
Standard version with
polyethylene (PE) gasket
For safety reasons and
to prevent the loss of the
door, retaining cables are
available with M6 bolt and
nut (Art. No. D01V-2001)
Ergonomic and corrosion
resistant POM knobs. Their
design prevents the bolts from
protruding
Galvanized or stainless
steel springs
Galvanized or stainless steel
cup square bolts with gasket ring
METU-SYSTEM Catalog 6b
61
Access Doors RD
RD Versions
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Polyethylene specifications: Additional Information ZI-201
Knobs specifications: Additional Information ZI-301
Material specifications: Additional Information ZI-101
Version with Self-Adhesive Rubber Edge Molding:
(it is wrapped along the edges of the duct opening,
serves as gasket and prevents injuries)
With Rubber Edge Molding (SKK) and POM knobs
Operating Temperature: max. +80°C
SKK specifications: Additional Information ZI-204
Version for higher Temperatures:
With Vitreous Fiber Gasket (KF) and Metal knobs (HT)
Operating Temp.:
Galv. steel version max. +200°C
Stainless V2A version max. +300°C
Vitreous fiber specifications: Additional Information ZI-206
Material specifications: Additional Information ZI-101
Notice: The glue holding the vitreous fibers might be destroyed above
200°C. We therefore recommend to replace the gasket after each
opening of the access door.
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Silicon specifications: Additional Information ZI-211
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs (HT)
Operating Temperature: max. +200°C
Silicon specifications: Additional Information ZI-211
Higher resistances to abrasion and better aerodynamic properties are achieved with the access door fitted with a 3rd
plate (3PL) spot welded onto the inner access door cover plate. Since this 3rd plate also insulates the access door,
these access door versions are also described in the „Insulated Access Doors IRD-3PL“ rubric.
62
METU-SYSTEM Catalog 6b
Access Doors RD
Installation Instructions
1
Apply the self-adhesive template on
the duct wall at the desired position
2
Cut the opening following
the edge of the template
For access doors ordered with
SKK rubber edge molding
The SKK molding is fitted with injected
glue. It can be applied on duct walls
up to 2 mm thick (Gauge ≈14)
The thicker lip of the SKK
must be inside the duct
Apply the SKK molding so that the
duct wall enters as deeply as possible
into the pocket. Both ends should meet
at a straight section, pressing slightly
against each other but without overlapping. To cut the insulation properly we
recommend the use of the Original
Loewe Scissors (Art. No. G04V-1005)
3
Turn the knobs till they hit the stops
and insert the inner door panel inside
the opening at an angle.
Then straighten the door, pull it lightly
to center it and tighten the knobs.
METU-SYSTEM Catalog 6b
63
Access Doors GX
• For rectangular ducts
• The bolts do not stick out, thus
avoiding dangerous protrusions.
• Ideal when space is restricted,
or when the door shouldn´t stick
out for security reasons
(in garages for example)
• The groove on the outer cover
facilitates the positioning of the
access door into the opening
• Oil-tight version available (with
NBR seals)
• Available in three sizes:
200 x 100 mm
300 x 200 mm
400 x 300 mm
International
Patents
The door sits deeper into the
duct, making it more discrete
and eliminating dangerous
protrusions (safety aspect)
Standard version with
polyethylene (PE) gasket
64
Ergonomic and corrosion resistant POM knobs. Their design
prevents the bolts from
protruding
The groove on the outer
cover facilitates the
positioning of the access
door into the opening
The aerodynamic characteristics limit
turbulences and the deposit and
accumulation of dust and dirt
METU-SYSTEM Catalog 6b
Access Doors GX
GX Versions
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Polyethylene specifications: Additional Information ZI-201
Knobs specifications: Additional Information ZI-301
Material specifications: Additional Information ZI-101
Version with Self-Adhesive Rubber Edge Molding:
(it is wrapped along the edges of the duct opening,
serves as gasket and prevents injuries)
With Rubber Edge Molding (SKK) and POM knobs
Operating Temperature: max. +80°C
SKK specifications: Additional Information ZI-204
Version for higher Temperatures:
With Vitreous Fibers Gasket (KF) and Metal knobs (HT)
Operating Temp.: max. +200°C
Vitreous fibers specifications: Additional Information ZI-206
Material specifications: Additional Information ZI-101
Notice: The glue holding the vitreous fibers might be destroyed above
200°C. We therefore recommend to replace the gasket after each
opening of the access door.
Oil-tight Version:
With NBR gasket and POM knobs
Operating Temperature: max. +80°C
NBR specifications: Additional Information ZI-210.
Air-tightness: better than the highest class D (DIN EN 12237)
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Silicon specifications: Additional Information ZI-211
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs (HT)
Operating Temperature: max. +200°C
Silicon specifications: Additional Information ZI-211
METU-SYSTEM Catalog 6b
65
Access Doors GX
Installation Instructions
1
Apply the self-adhesive template on
the duct wall at the desired position
2
Cut the opening following
the edge of the template
For access doors ordered with
SKK rubber edge molding:
The SKK molding is fitted with injected
glue. It can be applied on duct walls
up to 2 mm thick (Gauge ≈14)
The thicker lip of the SKK
must be inside the duct
Apply the SKK molding so that the
duct wall enters as deeply as possible
into the pocket. Both ends should meet
at a straight section, pressing slightly
against each other but without overlapping. To cut the insulation properly we
recommend the use of the Original
Loewe Scissors (Art. No. G04V-1005)
3
Turn the knobs till they hit the stops
and insert the inner door panel inside
the opening at an angle.
Then straighten the door, pull it lightly
to center it and tighten the knobs.
66
METU-SYSTEM Catalog 6b
Access Doors LX
• Time-saving access door
version for rectangular ducts
• Two levers allow the opening
or the closing of the access
door within seconds
• The bolts do not stick out, thus
avoiding dangerous protrusions
• Ideal when space is restricted,
or when the door should not
stick out for security reasons
(in garages for example)
• The groove on the outer cover
facilitates the positioning of the
access door into the opening
• Security locks prevent an
accidental opening
• Available in two sizes:
300 x 200 mm
400 x 300 mm
International
Patents
The pressure
exerted by the
levers can be
adjusted by
rotating them
Once the levers are
closed any dangerous
protrusions are
eliminated
Standard version with
polyethylene (PE) gasket
METU-SYSTEM Catalog 6b
Comfortable
POM levers for a
very quick and time
saving operation
The groove on the outer
cover facilitates the
positioning of the access
door into the opening
Security-locks mounted on
each lever allow to lock them in
the closed position
Lever location and
dimensions change
according to door
dimensions
The aerodynamic characteristics limit
turbulances and the deposit and
accumulation of dust and dirt.
67
Access Doors LX
LX Versions
Version:
With Polyethylene (PE) Gasket and Levers
Operating Temperature: max. +70°C
Polyethylene specifications: Additional Information ZI-201
Lever specifications: Additional Information ZI-301
Material specifications: Additional Information ZI-101
Version with Self-Adhesive Rubber Edge Molding:
(it is wrapped along the edges of the duct opening,
serves as gasket and prevents injuries)
With Rubber Edge Molding (SKK) and Levers
Operating Temperature: max. +80°C
SKK specifications: Additional Information ZI-204
Version for the Food Industry:
With Silicon Gasket and Levers
Operating Temperature: max. +80°C
Silicon specifications: Additional Information ZI-211
68
METU-SYSTEM Catalog 6b
Access Doors LX
Installation Instructions
1
Apply the self-adhesive template on
the duct wall at the desired position
2
Cut the opening following
the edge of the template
For access doors ordered with
SKK rubber edge molding
The SKK molding is fitted with injected
glue. It can be applied on duct walls
up to 2 mm thick (Gauge ≈14)
The thicker lip of the SKK
must be inside the duct
Apply the SKK molding so that the
duct wall enters as deeply as possible
into the pocket. Both ends should meet
at a straight section, pressing slightly
against each other but without overlapping. To cut the insulation properly we
recommend the use of the Original
Loewe Scissors (Art. No. G04V-1005)
3
4
METU-SYSTEM Catalog 6b
Door installation:
Open both levers and insert the inner
door panel inside the opening at an
angle. Then straighten the door and
push it lightly against the duct wall:
it will automatically position itself
correctly. Close levers simultaneously
until they lock.
If the levers can be closed too easily
(the gasket is not squeezed enough),
open the levers and turn them once
360° clockwise.
If, on the contrary, the levers close too
heavily (they do not lock completely),
open the levers and turn them once
360° counter-clockwise.
Then switch both security locks (refer
to picture 5) into the „locked“ position
to avoid any accidental opening.
69
Access Doors RRD
• For round ducts
•
Available in five sizes
180 x 80 mm
200 x 100 mm
300 x 200 mm
400 x 300 mm
500 x 400 mm
• For duct-Ø 68 to 1800 mm
(not all opening dimensions)
• In galvanized steel, stainless
steel and aluminum
• The duct wall is clamped
between two stable covers
• Two knobs allow a comfortable
handling and operation of the
access door
Locking nuts prevent
the knobs from being
totally removed
Press formed, strong and attractive
in appearance, the covers are
available in galv. steel, stainless
steel and aluminum
Ergonomic and corrosion
resistant POM knobs. Their
design prevents the bolts
from protruding
For safety reasons and to prevent
the loss of the door, retaining
cables are available with M6 bolt
and nut (Art.No. D01V-2001)
Galvanized or stainless
steel springs
Standard version with
polyethylene (PE) gasket
70
Galvanized or stainless steel
cup square bolts with gasket ring
METU-SYSTEM Catalog 6b
Access Doors RRD
RRD Versions
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Polyethylene specifications: Additional Information ZI-201
Knobs specifications: Additional Information ZI-301
Material specifications: Additional Information ZI-101
Version with Self-Adhesive Rubber Edge Molding:
With Rubber Edge Molding (SKK) and POM knobs
Operating Temperature: max. +80°C
SKK specifications: Additional Information ZI-204
The self-adhesive rubber edge molding is wrapped along
the edges of the duct opening, serves as gasket and
prevents injuries.
Version for higher Temperatures:
With Vitreous Fibers (KF) Gasket and Metal knobs (HT)
Operating Temp.:
Galv. steel version max. +200°C
Stainless V2A version max. +300°C
Vitreous fibers specifications: Additional Information ZI-206
Material specifications: Additional Information ZI-101
Notice: The glue holding the vitreous fibers might be destroyed above
200°C. We therefore recommend to replace the gasket after each
opening of the access door.
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Silicon specifications: Additional Information ZI-211
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs (HT)
Operating Temperature: max. +200°C
Silicon specifications: Additional Information ZI-211
METU-SYSTEM Catalog 6b
71
Access Doors RRD
RRD Opening Dimensions According to Duct Diameters
Access door dimensions also available
for larger duct-Ø as special versions
upon request
1800 mm Ø
1600 mm Ø
1500 mm Ø
1400 mm Ø
1300 mm Ø
1200 mm Ø
5
RRD 54
Opening size 500 x 400 mm
for 520 to 1800 mm duct diameters
1100 mm Ø
1000 mm Ø
900 mm Ø
4
RRD 43
Opening size 400 x 300 mm
for 370 to 950 mm duct diameters
800 mm Ø
700 mm Ø
600 mm Ø
500 mm Ø
3
RRD 32
Opening size 300 x 200 mm
for 260 to 530 mm duct diameters
400 mm Ø
200 mm Ø
100 mm Ø
68 mm Ø
72
2
RRD 21
Opening size 200 x 100 mm
for 130 to 360 mm duct diameters
1
RRD 18
Opening size 180 x 80 mm
for 68 to 170 mm duct diameters
METU-SYSTEM Catalog 6b
Access Doors RRD
Installation Instructions
1
Apply the self-adhesive template on
the duct wall at the desired position
2
Cut the opening following
the edge of the template
For access doors ordered with
SKK rubber edge molding:
The SKK molding is fitted with injected
glue. It can be applied on duct walls
up to 2 mm thick (Gauge ≈14)
The thicker lip of the SKK
must be inside the duct
Apply the SKK molding so that the
duct wall enters as deeply as possible
into the pocket. Both ends should meet
at a straight section, pressing slightly
against each other but without overlapping. To cut the insulation properly we
recommend the use of the Original
Loewe Scissors (Art. No. G04V-1005)
3
Turn the knobs till they hit the stops
and insert the inner door panel inside
the opening at an angle.
Then straighten the door, pull it lightly
to center it and tighten the knobs.
METU-SYSTEM Catalog 6b
73
Insulated Access
Doors IRD
• For insulated rectangular ducts
- outside insulation
- inside insulation (not for all
opening sizes)
• For 20 to 55 mm insulation
thicknesses
• The cut edge of the insulation is
protected by a cover plate
• The cover plate is maintained
in place and connected to the
duct without generating thermal
bridges thanks to a special
rubber profile
• The air pocket between the outer
and inner plates provide an
adequate thermal insulation
Locking nuts prevent
the knobs from being
totally removed
Ergonomic and corrosion resistant
POM knobs. Their design prevents the
bolts from protruding
Cover plate protecting the
cut edge of the insulation and
preventing the shedding of
loose fibers while esthetically
pleasing
Press formed, strong and attractive in
appearance, the covers are available
in galvanized steel, stainless steel
and aluminum
Duct wall
Insulation
The air pocket between the outer
and inner plates provides a good
thermal insulation
Galvanized or stainless steel cup
square bolts with gasket rings
74
Special rubber profile holding the
cover plate to the duct while
providing a thermal break
Galvanized or
stainless steel springs
METU-SYSTEM Catalog 6b
Insulated Access Doors IRD
IRD Versions
Insulated Access Door IRD-2
For insulation thicknesses from 20 to 30 mm
(≈ 0,79 to 1,18 in). The insulation must be soft.
Clearance = 19 mm
Operating temperature: max. +80°C (176°F)
Duct wall thickness: max. 2,0 mm
7 mm
Insulated Access Door IRD-3
For insulation thicknesses from 30 to 40 mm
(≈ 1,18 to 1,58 in). The insulation must be soft.
Clearance = 29 mm
Operating temperature: max. +80°C (176°F)
Duct wall thickness: max. 2,0 mm
7 mm
Insulated Access Door IRD-4
For insulation thicknesses from 40 to 55 mm
(≈ 1,58 to 2,17 in). The insulation must be soft.
Clearance = 39 mm
Operating temperature: max. +80°C (176°F)
Duct wall thickness: max. 2,0 mm
15 mm
Insulation inside the Duct
The above information are also valid when the insulation is
inside the duct.
If the duct is not installed yet, all eleven IRD dimensions can be
installed, assuming that the duct is large enough (see general
access door characteristics).
If the duct is already installed, and because the cover plates
cannot be inserted in all openings, only the following access
door sizes can be installed: IRD 42, 53, 64 and 75.
IRD rubber profile specifications: Additional Information ZI-209
Knobs specifications: Additional Information ZI-301
Additional Insulating Measures
In order to limit eventual convection currents in
the air-pockets, insulation chunks (which has been
removed to install the access door) can be stuffed
between the duct wall and the cover plate (1) and/or
between the access door covers (2).
METU-SYSTEM Catalog 6b
1
2
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75
Insulated Access Doors IRD
Installation Instructions
Cut the insulation according to the
depicted information
1
Cover Plate
27 mm
2
If the insulation is relatively dense,
the cut edge should be tapered
approximately 10 mm
Insulation
10
mm
60 mm
Cut edge alined
Duct wall
3
To cut the insulation use the cover
plate as a template and mark
around the outer edge. Then cut
out the insulation approximately
20 mm (0,79 in) inside the mark
Use the cover plate to make the
duct opening by marking around the
inner edge and cutting carefully
following this mark
4
The cover plate is secured by a
rubber profile. Begin fitting at a
straight section, the duct wall in
one groove of the rubber and
the cover plate in the other
5
The rubber profile is supplied at the
correct length for each door size.
Join the rubber ends as illustrated,
and push them into place
6
To install the Access Door
unscrew both knobs fully and,
using both hands,
place the door in the
opening at an angle
7
Then turn it straight and pull it
slightly out to align. Finish by
tightening the knobs
8
87 mm
All Insulated Access Door sizes
can be used on outside insulated
ductwork. However, for inside
insulated ductwork, only the
following Insulated Access Door
sizes can be installed:
IRD 42, IRD 53, IRD 64
and IRD 75
76
METU-SYSTEM Catalog 6b
SPECIAL: Insulated Access Doors IRD-3PL
• For rectangular ducts with outside or inside insulation
• For insulation thicknesses above 55 mm
• This access door is actually a standard RD fitted with a 3rd plate (3PL) which has been spot welded
onto the inner cover plate, creating a hollow space filled with insulation.
• Aerodynamic: the smooth inner surface created by the 3rd plate offers the least resistance to the air-flow.
• Abrasion resistance: the 3rd plate can also be made of a thicker material gauge in order to resist the rapid
wearing created by the transport of grinding dusts or wood shavings for example.
• The insulating properties are inferior to those of the IRD access doors, as thermal bridges can occur on
some areas (A).
A
The cut edges of the insulation should be covered (i.e. with an aluminum tape) in order to avoid chunks flying away.
This should especially be done when the insulation is inside the duct, in order to avoid contaminating the air inside the
ventilation system.
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Version with Self-Adhesive Rubber Edge Molding:
With Rubber Edge Molding (SKK) and POM Knobs
Operating Temperature: max. +80°C
Version for higher Temperatures (HT):
With Vitreous Fibers Gasket (KF) and Metal Knobs
Operating Temp.:
Galv. steel: max. +200°C
Stainless V2A: max. +300°C
Notice: The glue holding the vitreous fibers might be
destroyed above 200°C. We therefore recommend to
replace the gasket after each opening of the access door.
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs
Operating Temperature: max. +200°C
METU-SYSTEM Catalog 6b
77
SPECIAL: Insulated Access Doors IRD-3DE
• For rectangular ducts with outside insulation (not suitable for ducts with inside insulation)
• Designed for thicker insulations, depending on the access door dimensions (please refer to the table below).
• The IRD-3DE is characterized by a 3rd, larger cover plate which is placed on top of the insulation outside the
duct and minimizes any thermal bridges.
• The cut edge of the insulation is covered by the larger cover plate and offers a pleasing appearance.
• The air pocket trapped between the 3rd cover plate ad the access door provides good insulating properties.
The 3rd cover plate should
only apply a light pressure on the
soft insulating material: the knobs
must therefore be tightened lightly
In order to avoid any convection currents,
insulation chunks can be stuffed into the
hollow spaces of the access door
The inside covers guarantee the airtightness of the access door.
Knobs must be fastened securely
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs (*)
Operating Temperature: max. +70°C
Version with Self-Adhesive Rubber Edge Molding:
With Rubber Edge Molding (SKK) and POM Knobs (*)
Operating Temperature: max. +80°C
Version for higher Temperatures:
With Vitreous Fibers (KF) Gasket and Metal Knobs (*)
Operating Temp.:
Galv. steel: max. +200°C
Stainless V2A: max. +300°C
Notice: The glue holding the vitreous fibers might be
destroyed above 200°C. We therefore recommend to
replace the gasket after each opening of the access door
Version for the Food Industry:
With Silicon Gasket and POM Knobs (*)
Operating Temperature: max. +80°C
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs (*)
Minimum Insulation
Thicknesses
Approximative values
IRD-3DE 21: 42 mm
IRD-3DE 32: 55 mm
IRD-3DE 42: 55 mm
IRD-3DE 43: 60 mm
IRD-3DE 53: 60 mm
IRD-3DE 54: 75 mm
IRD-3DE 64: 75 mm
IRD-3DE 65: 80 mm
IRD-3DE 75: 80 mm
These values correspond to the bolt height
plus approx. 5 mm, as
the insulation is usually
soft and can be slightly
compressed by the 3rd
cover.
(*)
Using metal knobs
would reduce the
minimum insulation
thickness by about
20 mm.
Operating Temperature: max. +200°C
78
METU-SYSTEM Catalog 6b
SPECIAL: Insulated Access Doors IRD-DW1
• For double-wall rectangular ducts and ducts made of sandwich-type pre-insulated duct panels
covered on both sides with an aluminum foil.
• For insulation thicknesses from 10 to 60 mm. There are maximum insulation thicknesses to be taken
into consideration depending on the access door dimensions (please refer to the table below).
• The IRD-DW1 is a standard RD access doors with longer bolts.
• The insulation between the ducts must be hard enough in order to resist the pressure exerted
by the access door. Should that not be the case, the ducts might be deformed and the air-tightness
of the access door might not reach the DIN EN 12237 class C.
Knobs must be fastened securely.
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Version with Self-Adhesive Rubber Edge Molding:
With Rubber Edge Molding (SKK) and POM Knobs
Operating Temperature: max. +80°C
Version for higher Temperatures:
With Vitreous Fibers (KF) Gasket and Metal Knobs
Operating Temp.:
Galv. steel: max. +200°C
Stainless V2A: max. +300°C
Notice: The glue holding the vitreous fibers might be
destroyed above 200°C. We therefore recommend to
replace the gasket after each opening of the access door.
In order to avoid any convection currents, insulation chunks can be stuffed
into the hollow spaces of the access
door.
Maximum Insulation
Thicknesses
Approximative values
IRD-DW1 18: 20 mm
IRD-DW1 21: 30 mm
IRD-DW1 315: 30 mm
IRD-DW1 32: 30 mm
IRD-DW1 42: 40 mm
IRD-DW1 43: 40 mm
IRD-DW1 53: 50 mm
IRD-DW1 54: 50 mm
IRD-DW1 64: 60 mm
IRD-DW1 65: 60 mm
IRD-DW1 75: 60 mm
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs
Operating Temperature: max. +200°C
METU-SYSTEM Catalog 6b
79
SPECIAL: Insulated Access Doors IRD-DW2-Solution
• For double-wall rectangular ducts.
• For thicker insulations; depending on the access door sizes there are minimum
insulation thicknesses to be taken into consideration.
• This solution is made of two separate RD access doors.
• Since this solution consists of two independent access doors, they can be selected
in accordance with the specifications and requirements of each duct (see example below).
• This solution provides optimal insulation properties, as there are no thermal bridges and
a large air-pocket trapped between the access doors.
In order to avoid any convection
currents, insulation chunks can be
stuffed into the hollow spaces of the
access door
Example:
Outer Duct: RD Access Door
Material: galvanized steel with polyethylene (PE)
gasket and POM knobs.
Operating temperature: max. +70°C
Inner Duct for higher temperatures and hygiene
requirements: RD HT V2A Access Door
made of stainless steel (V2A) with silicon gasket
and stainless steel knobs (V2A).
Operating temperature: max. +200°C
There are numerous combination possibilities.
When choosing the access door dimensions, the
minimum insulation thickness must be taken into account.
Different opening dimensions can also be combined.
Usually smaller openings are made on the inner duct, and
larger ones on the outer duct to improve accessibility.
Should you need any help to decide which door would be
the most suitable, please do not hesitate to contact us.
80
Minimum Insulation
Thicknesses
Approximative values
IRD-DW2 18: 42 mm
IRD-DW2 21: 42 mm
IRD-DW2 315:55 mm
IRD-DW2 32: 55 mm
IRD-DW2 42: 55 mm
IRD-DW2 43: 60 mm
IRD-DW2 53: 60 mm
IRD-DW2 54: 75 mm
IRD-DW2 64: 75 mm
IRD-DW2 65: 80 mm
IRD-DW2 75: 80 mm
The above indications
correspond to the
combination of two
access doors having
the same opening
dimensions. Choosing
access doors with
different opening
dimensions might
somewhat reduce
the a.m. values.
METU-SYSTEM Catalog 6b
SPECIAL: Insulated Access Doors IRRD-3PL
• For circular ducts with outside or inside insulation
• Suitable for all insulation thicknesses
• This access door is actually a standard RRD fitted with a 3rd plate (3PL) which has been spot welded
onto the inner cover plate, creating a hollow space filled with insulation.
• Aerodynamic: the smooth inner surface created by the 3rd plate offers the least resistance to the air-flow.
• Abrasion resistance: the 3rd plate can also be made of a thicker material gauge in order to resist the rapid
wearing created by the transport of grinding dusts or wood shavings for example.
The cut edges of the insulation should be covered
(i.e. with an aluminum tape) in order to avoid chunks
flying away. This should especially be done when the
insulation is inside the duct, in order to avoid
contaminating the air.
A
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Version with Self-Adhesive Rubber Edge Molding:
With Rubber Edge Molding (SKK) and POM Knobs
Operating Temperature: max. +80°C
Version for higher Temperatures:
With Vitreous Fibers (KF) Gasket and Metal Knobs
Operating Temp.:
Galv. steel: max. +200°C
Stainless V2A: max. +300°C
Notice: The glue holding the vitreous fibers might be
destroyed above 200°C. We therefore recommend to
replace the gasket after each opening of the access door.
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs
Operating Temperature: max. +200°C
METU-SYSTEM Catalog 6b
81
SPECIAL: Insulated Access Doors IRRD-3DE
• For circular ducts with outside insulation (not suitable for round ducts with inside insulation)
• Minimum insulation thicknesses apply depending on the access door dimensions (please refer to the table
below).
• The IRRD-3DE is characterized by a 3rd, larger cover plate which is placed on top of the insulation outside
the duct and minimizes any thermal bridges.
• The cut edge of the insulation is covered by the larger cover plate and offers a pleasing appearance.
• The air pocket trapped between the 3rd cover plate and the access door provides good insulating properties
The 3rd cover plate should only apply
a light pressure on the soft insulating
material: the knobs must therefore
be tightened lightly.
In order to avoid any convection
currents, insulation chunks can
be stuffed into the hollow spaces
of the access door.
The inside covers guarantee
the air-tightness of the access door.
Knobs must be fastened securely.
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs (*)
Operating Temperature: max. +70°C
Version
with Self-Adhesive Rubber Edge Molding:
:
With Rubber Edge Molding (SKK) and POM Knobs (*)
Operating Temperature: max. +80°C
Version for higher Temperatures:
With Vitreous Fibers (KF) Gasket and
POM Knobs outside, Metal Knobs inside (*)
Operating Temp.:
Galv. steel: max. 200°C
Stainless V2A: max. +300°C
Notice: The glue holding the vitreous fibers might be
destroyed above 200°C. We therefore recommend to
replace the gasket after each opening of the access door
Minimum Insulation
Thicknesses
Approximative values
IRRD-3DE 18: 42 mm
IRRD-3DE 21: 45 mm
IRRD-3DE 32: 60 mm
IRRD-3DE 43: 65 mm
These values correspond to the bolt
height plus ≈5 mm, as
the insulation is usually
soft and can be slightly
compressed by the 3rd
cover.
(*)
Using metal knobs
would reduce the
minimum insulation
thickness by about
20 mm.
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and
POM Knobs outside, Metal Knobs inside (*)
Operating Temperature: max. +200°C
82
METU-SYSTEM Catalog 6b
SPECIAL: Insulated Access Doors IRRD-DW1
• For double-wall circular ducts.
• For insulation thicknesses from 10 to 50 mm. There are maximum insulation thicknesses to be taken
into consideration depending on the access door dimensions (please refer to the table below).
• The IRRD-DW1 is a standard RRD access doors with longer bolts.
• The insulation between the ducts must be hard enough in order to resist the pressure exerted
by the access door. Should that not be the case, the ducts might be deformed and the air-tightness
of the access door might not reach the DIN EN 12237 class C.
Knobs must be fastened securely.
Standard Version:
With Polyethylene (PE) Gasket and POM Knobs
Operating Temperature: max. +70°C
Version
with Self-Adhesive Rubber Edge Molding:
:
With Rubber Edge Molding (SKK) and POM Knobs
Operating Temperature: max. +80°C
Version for higher Temperatures:
With Vitreous Fibers (KF) Gasket and Metal Knobs
In order to avoid any convection
currents, insulation chunks can be
stuffed into the hollow spaces of the
access door.
Maximum Insulation
Thicknesses
Approximative values
IRRD-DW1 18: 20 mm
IRRD-DW1 21: 30 mm
IRRD-DW1 32: 30 mm
IRRD-DW1 43: 40 mm
Higher Thicknesses
are eventually possible, but the installation
of the door will be
difficult.
Operating Temp.:
Galv. steel: max. +200°C
Stainless V2A: max. +300°C
Notice: The glue holding the vitreous fibers might be
destroyed above 200°C. We therefore recommend to
replace the gasket after each opening of the access door.
Version for the Food Industry:
With Silicon Gasket and POM Knobs
Operating Temperature: max. +80°C
Version for the Food Industry and higher Temperatures:
With Silicon Gasket and Metal Knobs
Operating Temperature: max. +200°C
METU-SYSTEM Catalog 6b
83
SPECIAL: Insulated Access Doors IRRD-DW2-Solution
• For double-wall circular ducts.
• For thicker insulations; depending on the access door sizes there are minimum
insulation thicknesses to be taken into consideration.
• This solution is made of two separate RRD access doors.
• Since this solution consists of two independent access doors, they can be selected in
accordance with the specifications and requirements of each duct (see example).
• This solution provides optimal insulation properties, as there are no thermal bridges and
a large air-pocket trapped between the access doors.
In order to avoid any convection
currents, insulation chunks can be
stuffed into the hollow spaces of the
access door.
Example:
Outer Duct: RRD Access Door
made of galvanized steel with polyethylene (PE)
gasket and POM knobs.
Operating temperature: max. +70°C
Inner Duct for higher temperatures and
hygiene requirements: RRD HT V2A Access Door
made of stainless steel (V2A) with silicon gasket and
stainless steel knobs (V2A).
Operating temperature: max. +200°C
There are numerous combination possibilities. When
choosing the access door dimensions, the minimum
insulation thickness must be taken into account.
Different opening dimensions can also be combined.
Usually smaller openings are made on the inner duct, and
larger ones on the outer duct to improve accessibility.
Should you need any help to decide which door would be
the most suitable, please do not hesitate to contact us.
84
Minimum Insulation
Thicknesses
Approximative values
IRRD-DW2 18: 42 mm
IRRD-DW2 21: 42 mm
IRRD-DW2 32: 55 mm
IRRD-DW2 43: 60 mm
IRRD-DW2 54: 75 mm
The above indications
correspond to the combination of two access
doors having the same
opening dimensions.
Choosing access
doors with different
opening dimensions
might somewhat
reduce the above
mentioned values.
METU-SYSTEM Catalog 6b
Special Access Doors Questionnaire
If you haven´t found the information for your requirements in this catalog and you need assistance with your access
door choice, thank you for answering the questions below and for sending this questionnaire back to:
Fax No.: 0049 (0)7461 9287 28 or E-mail address: info@metu.de
QUESTIONNAIRE FOR SPECIAL ACCESS DOORS
From:
Company Name:
Client No.
Contact:
Phone:
E-mail:
Rectangular Ductwork
dimensions: width _______ mm x height ________ mm x length ________ mm
rectangular, without insulation
rectangular with outside insulation
insulation thickness: _______ mm
rectangular with inside insulation
insulation thickness: _______ mm
rectangular double wall
insulation thickness: _______ mm
Circular Ductwork
circular without insulation
circular with outside insulation
circular double wall
duct-Ø _________ mm
outer Ø _______ mm / inner Ø _______ mm
insulation thickness: _______ mm
outer Ø _______ mm / inner Ø _______ mm
insulation thickness: _______ mm
Other indications and requirements
Required opening size: __________ x __________ mm
Required quantity: _________ pieces
Operating temperature: _______ °C
Ductwork material (galv.,aluminium, stainless 304 or 316Ti):
Insulation Material (soft, hard, covered with aluminium foil):
Other requirements / remarks:
METU-SYSTEM Catalog 6b
85