Fabric Ducting & Diffusers

32
FABRIC DUCTING&DIFFUSERS Technical data Tailor-made Air Ducting&Diffusers English version

description

Prihoda fabric ducting and diffusers general technical data

Transcript of Fabric Ducting & Diffusers

Page 1: Fabric Ducting & Diffusers

FABRICDUCTING&DIFFUSERS

Technical data

Tailor-made Air Ducting&Diffusers

English version

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Contents

1. FUNCTIONS OF FABRIC DUCTING&DIFFUSERS1.1. Air outlet from diffuser 1.2. Entry of air into the negative pressure ducting 1.3. Air conduction via ducting 2. BASIC CHARACTERISTICS OF PRODUCTS 2.1. Cross section2.2. Dimension2.3. Length2.4. Pressure 2.5. Type of endings3. INSTALLATION 4. SPECIFICATION5. DESIGN PARTICULARS5.1. Membrane diffuser5.2. Negative pressure ducting5.3. Insulated ducting5.4. Adjustable length5.5. Adjustable arch5.6. Nozzle5.7. Tensioners5.8. Reinforcing components5.9. Equalizers5.10. Damper 5.11. Diffuser for intensive cooling 5.12. Air diffuser Lantern 5.13. Defrost damper 5.14. Antistatic design 5.15. Moveable adapter 5.16. Winch 5.17. Other possibilities6. MATERIAL 7. MAINTENANCE AND WARRANTY 8. EXAMPLES OF APPLICATIONS9. FREQUENTLY ASKED QUESTIONS10. 5+5+5

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3366778899

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Tailor-made Air Ducting&Diffusers

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Functions of fabric ducting&diffusersOur products are generally simultaneously ducting as well as a distribution or collecting component. We distinguish overpressure distribution systems (fabric ducting&diffusers) and negative pressure (suction) ducting for exhausting air from rooms.

1.

Air outlet from diffuser1.1.Flow V brought into the diffuser through any of the ends or through the entry adapter may exit in the following manners:

A - through a permeable fabricB - through microperforation – 0.2 – 0.4 mm holes in the fabricC - through perforation – holes with a diameter greater than 4 mmD - through a nozzle – see chapter 5 for more detailsE - through an adapter – air is guided off into another ducting line F - through the second end – air leads to another diffuser or ducting

A B C D

Vair supply E

air outlet through an adapter

It always holds true that: V = A + B + C + D + E + F

(certain values of A, B, C, D, E, F may be zero)

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air outlet through other

side

F

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Tailor-made Air Ducting&Diffusers

Fabric diffusers are a universal air distribution tool and cover the entire range of applied flows in practice. We achieve the demanded flow range of air by selecting the correct air outlet method. We can combine the air outlet methods at a single diffuser arbitrarily.

Airflow reaches from fabric diffusers

Uniformmicroperforation

Directional microperforationPerforationNozzle

Air is distributed from fabric diffusers through variously large and variously distributed holes. The combination of size and distribution of holes together with various outlet flows provide an immeasurable number of variations. The range of possibilities begins through low-rate dispersion of air distribution and continues up to long-distance targeted air supply. Small holes with a diameter of 0.2 – 0.4 mm, which we refer to as microperforation, are designated for air dispersion. We use a series of 4 mm or larger holes, which we call perforations, to provide directed air supply. When calculating the flow rate at specific intervals, the temperature difference must be considered along with the output flow rate.

The airflow reaches vary in dependance on static pressure in the diffuser and on temperature difference.

0,2 m/s

0,2 m/s

0,2 m/s

0,2 m/s

10 -

30 m

3 -

12 m

0-3

m 0

- 1,

5 m

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The flow rate at various distances from the diffuser may be calculated by the design software that we constantly improve and develop, which takes into account all known influences. These include, in particular, overpressure in the diffuser, distribution and dimensions of outlet openings, and temperature difference. We are fully available to verify each calculation. In cases when the flow speed cannot be calculated reliably by our software (e.g. effects of the environment, interaction of more flows, etc.), we can provide calculation by means of Fluent software.

Airflow patterns created by PRIHODA design software

In general, fabric diffusers are used at similar flow speeds as traditional ducting. The maximum utilizable speed is limited by aerodynamic noise in relation to the place of use. Further limitations are represented by flow turbulences which might cause vibration of the fabric. Specific conditions of flow, static pressure and weight of the fabric used must be taken into account.

Examples of airflow patterns created through a smoke test in the PRIHODA testing centre

uniform microperforation

directed perforation

directed microperforation

close - up of air outlet from perforation

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Pozice 1 Úsek 1 Režim větrání Rozdíl teplot 0 ° C

0,500

0,420

0,330

0,250

0,170

0,080

0,000

m/s

Pozice 2 Úsek 1 Režim větrání Rozdíl teplot 0 ° C

0,500

0,420

0,330

0,250

0,170

0,080

0,000

m/s

Airflow patterns created by Fluent program

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1.2.

1.3.

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Tailor-made Air Ducting&Diffusers

Air conduction via ducting

Entry of air into the negative pressure ducting

Ducting made from impermeable fabric or insulated ducting (see chapter 5.3.) feeds air to the point of destination. We know how to produce branches, reducers and other fittings for any situation.

Perforations are used exclusively for air inlet into negative pressure ducting.

air outlet through an adapter

air inlet through perforation

air outlet

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Basic characteristics of products

Cross section

ONLY

OVE

RPRE

SSUR

E

C CIRCULARThe basic version, easy maintenance, preferentially recommended.

H HALF-ROUNDUse where there is not enough space for circular diffuser and in exacting interiors.

Q QUARTER-ROUND

Use where there is not enough space for circular diffuser, in exacting interiors and if the diffuser is to be installed in a corner of a room.

SG SEGMENTUse where there is not enough space even for a half-round diffuser.

SC SECTORIf the room corner construction requires different shape than quarter circle.

OVE

RPRE

SSUR

E AN

D NE

GATI

VE P

RESS

URE

S SQUAREThe shape can be retained only by means of a special structure holding at least all the corners of the diffuser.

T TRIANGULARThe diffuser cross section is maintained by stretching by means of a burden placed into the cross section bottom corner.

We produce also transitional parts among these sections.

The shape partially deforms despite good stretching, due to overpressure or negative pressure and the material flexibility (applies to cross sections S and T).

Half-round cross section Segment

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2.3.

Tailor-made Air Ducting&Diffusers

DimensionWe manufacture fabric ducting and diffusers of all dimensions from 100 to 2000 mm, based always on the particular specifications. The connecting part dimensions are always 10-15 mm larger than specified in the technical documentation for the order.

Basic series of A and B values:100, 125, 160, 200, 250, 315, 400, 500, 630, 710, 800, 900, 1 000, 1 120, 1 250, 1 400, 1 600, 1 800, 2 000

LengthDetermining the length of fabric ducting and diffusers depends primarily on the availability of space. Generally, the same air flow may be supplied into an area using a 1 to 200 m long diffuser. It depends only on the used material, its modification, and the fan delivery pressure.

MOST FREQUENT CASE

- Individual parts are connecting with zippers; the number of zippers may be modified per customer request.- Only the overall length in mm (thus A + B + C) is provided in the specification; ducting and diffusers are separated rrinto segments during production.

Dimension in individual shapes is understood to mean:

Shape Dimension (values A,B)

circular diameter (A)

half-round diameter (A)

quarter-round radius (A)

segment chord, height (A,B)

sector radius (A)

square length of edges (A,B)

triangular base, height (A,B)

A - beginning – length 100 - 200 mmB - continuous part – length 5000 – 10 000 mm, may be repeated several times in sequenceC - blind part – length from 1000 to 11000 mm

AB

C

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PressurePressure losses of fabric diffusers and ducting are very similar to those in the traditional ducting. Calculating a more complex fabric distribution system is achieved similarly to sheet metal ducting. Minimum static pressure necessary to keep the correct shape of a fabric diffuser or ducting depends on the weight of the fabric used. 20 Pa is sufficient for light materials and 50 Pa then for medium and heavy ones. The pressure distribution along fabric diffusers is different from common ducting because with declining airflow longitudinal velocity decreases. To verify the design of the distribution system or ducting, contact us.

2.4.

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Type of endings2.5.

F BEGINNING H HEMMING

WOUT OUTER WINGS WIN INNER WINGS

B BLANKING Z ZIP

S SUTURE

100-200 mm

Tailor-made Air Ducting&Diffusers

Graph of pressure distribution in a fabric diffuser

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Tailor-made Air Ducting&Diffusers

InstallationInstallation no. Cross section scheme Type of suspension Additional accessories

0 without mounting material and hooks or enlarged strips

1 wire D, F, K, M

2 wire D, F, K, M

3 profile, velcro A, B, C, G, J, L, H

4 profile B, C, G

5 suspended profile A, B, C, G, I, D, E, F, K, L, M

6 suspended profile A, B, C, G, I, D, E, F, K, L, M

7 tensioner D, F, H can be added to any other installation

8 profiles, velcro A (for triangle cross-section always),B, C, G, L, H, J

9 profiles A, D, E, F, K, L, M

10 profiles A, L

11 profiles A, E, K, L, M

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hooks aluminium profile plastic coated wire

wire cut

enlarged strip (A) plastic profile (B) aluminium profile with hangers (C)

wire hangers (D,F) thread bar (E) stainless profile (G)

reinforced aluminium profile (I) Velcro (J) Gripple hangers (M)

Tailor-made Air Ducting&Diffusers

untagged suspension by hooks and aluminium profile or by wire

A enlarged strip instead of hooks

B plastic profile

C aluminium profile with aluminium hangers

D stainless wire and stainless mounting material

E thread bar

F plastic coated wire and stainless mounting material

G stainless profile

H tensioner at blanking

I reinforced aluminium profile

J Velcro

K galvanized chain

L screw tensioner in the profile

M Gripple hangers

Overview of additional accessories

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Specification

C710/10000 A2 FB DD M EQS/PMS-2F NMM/LGO + INC710F EQr + 2OUT(2xC500Z) +

+ 710/R800 AArch-90°/4 SS+ DSC800x600-710/500 F/WOUT +TYp/IN/PL + 2DMr + AS

The specification may completely describe only simple diffusers or ducting. It is used for an approximate definition and does not generally suffice for an order. Most cases require a drawing or detailed description. The following items may appear in the specification:

1 SectionC - circular, H - half-round, Q - quarter-round, SG - segment, SC - sector, S - square, T - triangular, see chap. 2.1.

2 Type of ending F - beginning, Z - zip, H - hemming, S - suture, B - blanking, WOUT/WIN - outer/inside wings, see chap. 2.5.

3 Equalizer EQ - cone, EQS - star , EQP - pot, r - removable, see chap. 5.9.

4 Material

Permeability: P - permeable, N - non-permeableWeight: M - medium, H - heavy, L - lightCharacteristic: S - standard, E - excellent fire resistance, I - increased fire resistance. R - increased strength, F - foil/plastic coated, see chap. 6.

5 Installation type see chap. 3.

6 ColourWH - white, BL - blue, LB - light blue, LG - light grey, YE - yellow, DG - dark grey, GR - green, RE - red, BC - black, SP - special, GY - grey, see chap. 6.

7 Inlet adapter C(section)710(size)F(type of ending) EQ(equalizer)

8 Outlet adapter 2(number)C(section)500(size)Z(type of ending)

9 ArchA710(size)/R800(radius)Arch-90°(angle)/4(number of segments) SS(type of ending), without marking - segment, A - adjustable, S - longitudinal strips

10 ReducerD(reducer)S(section)C(section)800x600(first size)-710(second size)/500(length)F/WOUT(type of ending)

11 Reinforcing elements

TY - tyre, RA - racks, p - fixture for tyres only, IN/OUT, PL/ST/AL - plastic/stainless/aluminium, see chap. 5.8.

1

size

length

2x adjustable length

2

doublediffuser

membrane diffuser

3

4

5

no mounting material

6

office design

7

8

9

adjustable 10

11

2x damper

antistatic design

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5.

5.1.

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Tailor-made Air Ducting&Diffusers

Membrane diffuserThis combines two types of diffusers into one. The membrane, produced from a light impermeable fabric, is sewn horizontally into the centre of the diffuser. It covers either its top or bottom part in an alternating fashion. The front end of the membrane is fastened to a flap controlled by a servo motor. This makes it possible to select between two positions, usually cooling or heating. In heating applications, the membrane covers the top half of the diffuser and the air exists through a series of holes downwards. In cooling applications, the membrane covers the bottom half and the air exists only upwards through the fabric or microperforation.

heating cooling

FLAP: Used for switching between the two modes. It is made from PMS/NMS or PMI/NMI material (according to fire resistance); the internal design and external frame are made from galvanized steel. The length is always 400 mm. The flap includes a 220 V or 24 V servo motor.

membrane microperforation

row of holes

D <= 630 mm

DIFFUSER: The membrane always covers one half of the diffuser and leaves the other open to supply air.

CONDITIONS OF USE:- Maximum longitudinal velocity 6.0 m/s (risk of damage to membrane at higher velocities).- Only for round cross-sections.

Diffuser for 2 air outlet modes

Design particulars

D>630 mm

heig

ht o

f ins

talla

tion

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5.3.

Tailor-made Air Ducting&Diffusers

Negative pressure ducting Fabric ducting for air exhaust

May only be produced with a square or triangular cross-section. Perfect stretching of the fabric lengthwise and crosswise is essential to assure function. Lengthwise stretching is secured by screw tensioners in the profiles, crosswise stretching by threaded rods or weight if applicable (in triangle cross-sections). Air is suctioned into the ducting through perforation that may be arbitrarily placed along the length of the ducting. We resolve demands for equal exhaust of air by progressively modifying the span or size of the holes. We anticipate use where regular and complete cleaning of ducting is required. Negative pressure fabric ducting may be easily pulled out from the bearing structure, the parts separated using zippers, and everything washed. If PMI or NMI (contains silver) material is used, the ducting will have antibacterial properties.

Insulated ductingUsed for decreasing heat losses when overcoming non-air conditioned segments between the machine room and the resolved room. A 4 cm unwoven polyester layer is used as insulation and is sewn between the light internal and external, usually medium fabric. All of our materials are suitable for use as external layers. The process of sewing somewhat decreases the thickness of the insulation by as much as approx. 20 – 30 mm. The maximum achieved heat permeability coefficient is 1.8 W/m2K. We typically provide 2 m parts with diameters from 250 mm. Each 2 m has one reinforcement tyre. This insulated hose also has excellent noise dampening ability.

Thermal insulation and noise dampener

Square negative pressure fabric ducting with stretching frame

Sectional view of square negative pressure ducting Sectional view of triangle negative pressure ducting

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5.4.

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Adjustable length8 lengthwise adjustable tie belts are equally sewn around the circumference of the circular ducting. If we adjust them all to the same length, we effectively decrease the length. The ducting is thus able to quickly adapt to the situation at the work site.

CONDITIONS OF USE:- Adjustable part with maximum length of 1500 may be reduced to 500.- The diameter must be increased by approx. 25% to reach permissible local rrpressure losses.- Only for circular sections with diameter > 250mm.- Only from PMI, PMS, NMI, NMS, PLI, PLS, NLI, NLS materials. - Adjustable parts may not contain enlarged strips.

Adjustable arch

Shortening a particular belt turns the ducting in a certain direction. The bend angle is changed by variously setting the belt:

Placing two adjustable archs in sequence makes possible to bypass obstacles.

8 lengthwise adjustable tie belts (same as in adjustable length) are equally sewn around the circumference of the circular ducting.

Option of changing length during assembly

Angle may be adjusted during assembly

Length 500 Length 1000 Length 1500

Length 500 - sectional view Length 1000 - sectional view Length 1500 - sectional view

Close-up view of tie belt

30° 60° 90°

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Tensioners

Screw tensioners in the profile are used to even out creases in the fabric, folds created by folding into cartons, and any small non-precise stitching, if present. The pliability of the fabric allows stretching by up to 0.5% of the length. Non-stretched diffusers are thus 0.5% shorter than specified in drawings and the proper length is achieved through tensioners. The installation procedure is specified in the assembly instructions.

Significantly improve appearance

NozzleNozzles make it possible to deliver air at greater distances than perforations. Depending on the static pressure and temperature differential, the range may even exceed 20 m. Use our design software or contact us for. The nozzle may be fixed, adjustable or pointed. Both nozzles look roughly the same; the adjustable nozzle may be directed as desired up to ± 45° using 4 belts. Folds and belts covered in fabric. A damper is sewn into the nozzle to adjust the flow.

Fixed nozzle

For longest airflow reaches5.6.

Adjustable nozzle

5.7.

CONDITIONS OF USE: We recommend using whenever possible, i.e. in all aluminium profile installations.

Screw tensioner in the profile

Tensioner in blanking

anchored into the wall in the axis of the diffuser anchored into the profile on the ceiling (wall)

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Directed nozzle

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5.8.

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Tailor-made Air Ducting&Diffusers

Manufactured from heat resistant plastic (for diameters ≥ 400 mm), from stainless steel wire, or from flat aluminium profiles. They are installed internally or externally with a standard spacing of 500 mm, fastened with Velcro and disassembled during maintenance.

Reinforcing components

Tyres

Arcs

Used for improving ducting/diffuser shape without air inlet. Arcs ends are inserted into pockets sewn on the internal ducting wall; they are fastened in the middle by a Velcro attachment. They are disassembled during maintenance. It provides a cheaper alternative to tyres.

They are used to keep the shape of circular ducting, even though they are not inflated.

Maintaining the shape of circular ducting

Diffuser with arcs without air supplyInflated diffuser with arcs

Inflated diffuser with tyres Diffuser with tyres without air supply

Detailed view of internal plastic tyre fastening Diffuser with tyres without air supply

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EqualizersThey are used for equalizing flows, e.g. downstream of the fan or fitting. Their placement can remove vibrations of the fabric; nevertheless, it introduces additional pressure loss.

Damper

Airflow equalizing

Equalizing the static pressure distribution

5.9.

5.10.

5.11.

EQ EQS (star) EQP (pot) EQT (T-shape)perforated fabric cone star-shaped fabric sewn

into the diffusercylinder sewn from a per-forated fabric with bottom

equalizer copies inside form of diffuser

It is a truncated cone made of highly permeable fabric, whose lesser diameter may be adjusted using a sewn in belt with stopping clamp. Maximum opening to the diffuser diameter means zero pressure loss, and in contrast, fully closing provides highest local loss. The setting may be adjusted at any time by opening the zip-fastener. It serves to equalize the static pressure along a diffuser, thereby equalizing the outflow. It can be used for flow regulation from fabric nozzles and adapters.

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Diffuser for intensive coolingFor temperature difference over 6 K we recommend horizontal air outlet direction. This can be achieved by organizing micro-perforation in the line in the required direction. Flat current must achieve specific speed in order to prevent premature bending down. With sufficient outlet speed (static pressure) it is possible to introduce 1 kW of cool to 1 m outlet, and maintain speed in the dwelling zone under 0,2 m/s. The flow is illustrated on figures, contact our authorized representatives for the specific calculations.

Airflow patterns, mikroperforation 90°, 165 PaMikroperforation 90°

Cooling with high temperature difference

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5.12. Air diffuser Lantern Simple setting and directing the airflow

This air diffuser serves to distribute air supplied into the space above, most often from units on the roof. It may only be installed in a vertical position. The air is blown horizontally in one to six directions. Vertical sliding strips are used to regulate the flow rate.

Basic dataConnection D1 mm 200 315 400 500 630 710 800

Lantern D2 mm 400 630 800 1000 1260 1420 1600

Total length L1 mm 700 942 1170 1380 1653 1821 2060

Length L2 mm 500 684 820 980 1188 1316 1460

Airflow 80 Pa

50% open V m3/h 500 1240 2000 3125 4961 6301 8000

100% open V m3/h 1000 2480 4000 6250 9922 12602 16000

Weight M kg 1,0 2,1 3,2 4,9 7,5 9,3 11,7

D2

L2

D1

L1

Detail of settingclosed

Airflow setting

50% open 100% open

Drawing and photo of lantern

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Defrost damper Faster defrosting of coolers5.13.

The Defrost Damper (DeDa) serves to close the fan of an evaporator to speed up the process of defrosting.

FUNCTION : a) The Damper is open if the fan works and allows passing the cooling air through. The air volume is slightly limited by the damper. The exact value depends on the airflow curve of the fan and the construction of the damper.b)The fabric of the damper closes the fan due to gravitation if the cooler shuts down. It avoids the air passing through the cooler and the process of defrosting speeds up. CHARACTERISTICS: 1) Used fabric has special properties to provide good covering the cooler and not get icy (hydrophobic treament)2) Damper is connected to the cooler by a textile or metal strip. If there is not any adapter on the cooler, it must be made up. The adapter is not included in the supply.3) There is a tightening strip with a buckle at the end of damper, which serves for adjusting the diameter. During putting in operation is important to find the right size, which influences minimally the airflow but still avoids vibration of fabric.4) Length of Damper: 1,2 x diameter + 50 mm.

Detail of tightening strip

Defrost damper on the cooler

Tailor-made Air Ducting&Diffusers

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Antistatic design Elimination of voltage diffuser/earth5.14.

Scheme of antistatic design

The earthing point

The earthing point

The highly conductive strip

The metal joints

Moveable adapter Positioning the adapter5.15.Adapters on a straight part of a half-round or quarter-round diffuser can be designed in a way to be movable in the direction of the diffuser by even 80 mm. Moveable adapter can be helpful in case the real position of the adapter does not correspond to the one on the drawing. „INM“ symbolizes the moveable adapter in a specification (letter M attached to the symbol of a common adapter “IN”).

max. 80 mm max. 80 mm

Antistatic design is intended for rooms, where a voltage between ducting&diffuser and the earth must be avoided.It consists of 4 measures:1. A sufficiently conductive fabric (PMI and NMI conform)2. A highly conductive strip sewed lengthwise3. All the zippers equipped with metal joints4. Earthing points at the ends

The conductive fabric

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Other possibilities

Combined half-round section

Manometer

This is a combination of several half-round diffusers sewn together side-by-side. It enables higher flows at a relatively small height.

The static pressure in the textile diffuser can be detected using a simple manometer. Increased pressure above a specific value due to fouling may serve as an indicator to wash the diffuser.

We manufacture everything on order. We will gladly meet your demands if they differ from the design or equipment specified here. Contact us.

Winch Mounting and demounting from one place5.16.The whole diffuser can be pulled into the aluminium profiles from one place using a simple winch. This simplifies significantly assembling and disassembling. Such winch can be used in particular with installation over technological equipment where the outlets are not easy accessible.

CONDITIONS OF USE: It is only suitable for installation 5, 5D, 5F, 5I, 5DI, 5FI

Realing by the help of Acu -screwdriver

5.17.

Tailor-made Air Ducting&Diffusers

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Designation Permeability Weight Material Characteristic

PMS/NMS yes/no medium 100% polyester 9

PMI/NMI yes/no medium 100% polyester 9

PLS/NLS yes/no llight 100% polyester 9

PLI/NLI yes/no llight 100% polyester 9

NLF no light 100% polyethylene 1

NMF no medium 100% polyester +2x PVC 4

NHE no heavy 100% fibre glass+ 2x polyurethane 7

NMR no medium 100% polyester 1

NLW no light 85% polyester, 15% nylon 1

antib

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Key to the designation of fabric

f.r. = fire resistance

Ffoil or PVC

Sstandard

Iincreased f. r.

Rrigid

Ehighest f. r..

Wwater repellent

L70-120 g/m2

M180-350 g/m2

H460 g/m2

Ppermeable

Nimpermeable

Tailor-made Air Ducting&Diffusers

MaterialThe company PŘÍHODA s.r.o. focuses on the quality of the materials used. In all cases these are special fabrics that passed a long development phase in order to achieve as high utility value for customers as possible. The PMI/NMI fabrics provide all the below listed benefits already in the standard design (without any extra charge).

List of most important qualities of our fabrics

High rigidityOur basic PMS/NMS/PMI/NMI fabrics demonstrate optimum rigidity. In the texture it is 1800 N/10mm, and 1000 N/10mm in the woof. Thanks to these parameters, their rupture is practically out of the question.

High fire resistanceThe PMI/NMI fabrics are certified according to EN 13501-1 with an excellent result. They achieve B-s1,d0 classification, which means prevention of spread of fire, minimum effusion of smoke and no burning drops. NHE fabrics in fact meet class A requirements. PMI/PLI fabrics are also certified according to US norm UL 723.

Negligible outlet of par-ticles

Due to the use of endless fibres, our fabrics may without exception be used in so-called class 4 clean premises. Laboratory tests demonstrated practically zero release of particles from the material during operation.

Antistatic effect Woven carbon fibre in PMI/NMI materials removes an electric charge from the surface of the fabric.

Antibacterial effectSpecial treatment guarantees killing of bacteria that are settled in the fabric. This effect remains even after many washing cycles. After ten washing cycles, it still meets norm requirements, which practically means a permanent effect considering its low washing frequency (see following point).

Easy to maintainOur fabrics made of endless fibres are very practical and do not allow settlement of impurities from flowing air. This air is distributed through the holes, and the textile diffusers remain nearly clean inside (in a normal environment). They do not require other maintenance than outer dusting. Washing usually comes only due to sanitary or esthetical reasons.

Permanency of appearanceThanks to endless fibres, the appearance of the fabric does not change even after many washing cycles, unlike materials made of staple fibres. Our PMI/NMI/PMS/NMS‘s are not devalued by washing in any manner whatsoever.

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Tailor-made Air Ducting&Diffusers

How to choose a suitable fabric?

When selecting material, bear the following information on mind:

1/ Fire resistance

Our fabrics show 3 levels of fire resistance.

2/ Rigidity and cleaning ability

Fabrics are divided in 3 categories by weight.

3/ PermeabilityOnly in permeable materials condensation of water on the surface of diffusers is eliminated during cooling below the dew point of the environment.

4/ ColoursMost of our materials are available on regular basis in 9 colours that approximately correspond with the below colour spectrum. Requirement on a special colour shade usually means a longer delivery term.

Ask for a sample book if you wish to make a precise choice of your colour shade!

Peak fire resistance (marked by the letter specification E, as in „excellent”) means entirely inflammable material. In this class, considering the price, we only use fabrics of fibreglasses with polyurethane coating. However, these exist only impermeable and are less rigid and more fragile than polyester fabrics of medium weight.

Increased fire resistance (identified with “I” in the specification, as in “in-creased”) means highly inflammable and very small effusion of smoke. These materials meet the require-ments for use in an absolute majority of spaces.

Raw polyesters or foils (identified with the marking S as „standard“ or F as in “foil” in the specification) are very low resistant. They can be used in an environment where no fire resistance is required.

Light (marked “L” ). These are fabrics with a mass between 70 and 120 g/m2. Diffusers made of these materials only require 20 Pa of static pressure to achieve good inflation. On the other hand, they have lower rigidity and especially resistance to rupture. Except NLF they can be washed in a washing machine.

Medium (marked “M” ). In this class are fabrics with a mass between 180 and 350 g/m2. They display the highest rigidity and anti-tear resistance. The minimum overpressure for a good inflation is 40 Pa. They can be washed in a washing machine.

Heavy (marked “H” ). These are PVC or polyurethane-coated fabrics and therefore they can only be impermeable. They cannot be washed in a washing machine but can be cleaned with a stream of water. This makes them suitable for the most contaminated environments. The minimum overpressure for a good inflation is 50 Pa.

~RAL

901

6

PAN

TON

E 13

5 (R

AL 1

017)

PAN

TON

E 42

0(R

AL 7

035)

PAN

TON

E 42

4(R

AL 7

037)

PAN

TON

E 34

1(R

AL 6

024)

PAN

TON

E 18

7(R

AL 3

001)

PAN

TON

E 29

15(R

AL50

12)

PAN

TON

E 74

62(R

AL 5

005)

PAN

TON

E 41

9(R

AL 9

017)

WH YE LG DG GR RE LB BL BC

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Maintenance and warranty7. All our ducting&diffusers are made from high quality and highly resistant materials without natural fibre additives. The used material is specified during the technological processing of your order. Diffusers/ducting made of permeable fabrics (PMS, PMI, PLS, PLI) can be washed in a common industrial washing machine. Impermeable fabrics (NMS, NMI, NLI, NLS, NMR) may only be washed in a gentle cycle, NMF, NHE, and NLF materials must be washed by hand. If diffuser/ducting is equipped with tyres, braces or tensioning systems, then these fixed components need to be taken out before washing. Outer induction contamination can be usually removed by suction using a vacuum cleaner and washing is thus not necessary.

Washing procedure:

4. Lightly drain the product, install, and dry using a stream of fanned air.

1. Wash using general washing detergents (dosage as recommended by the manufacturer); enhance the effect by turning inside out. Depending on the level of fouling, we recommend repeating the washing cycle up to four times or to use a stronger washing detergent, as necessary.

2. If operating regulations at the place of installation require, add a disinfecting agent to the washing detergent. The disinfecting agent chemicals must not affect the used fabric (see maintenance symbols), apply detergent as per manufacturer recommendations.

3. Rinse repeatedly in clean water.

Legend for symbols

8Machine wash at max. temperature of 40°C, nor-mal mechanical action, normal rinse, normal spin cycle.

9Light mechanical action, rinse at falling temperature, light spin, gentle machine wash, max. temperature 40°C.

t hand wash only, do not machine wash, max. tempe-rature 40°C, handle gently.

o Do not bleach product.

s Product may be dried in rotary drum drier at reduced drying temperature.

d Do not dry the product in a rotary drum drier.

n Iron at a max. temperature of 110°C, use caution when steam ironing.

m Do not iron product; steaming and steam processing is prohibited.

U Do not dry clean product, do not remove spots using organic solvents.

W The product is safe to dry clean using perchlorethy-lene and all solvents specified under the symbol F.

Strictly follow the maintenance symbols on washing labels sewn by the zip-fasteners.

washing label

Warranty period starts on the day of sale.The warranty condition is the compliance with all instructions for the assembly and maintenance, and also general principles for maintenance of air-conditioning units. The warranty condition is also inlet air filtration at least EU3, and provable washing and cleaning (if washing is not permitted) at least once a year. The product must not be exposed to the effects of materials, which can have adverse chemical effects.

Warranty

Special conditions for diffusers with printings

1. Temperature of surrounding from +10 to + 40 °C.2. Do not iron.

Warranty period

10 year fabrics PMS/NMS/PMI/NMI/NMR

2 yearmembrane diffuser, fabrics NMF/NLF/NHE

2 year (max. 50washing cycle)

fabrics PLS/NLS/PLI/NLI

12 měsícůOther than specified materials, unwoven accessories (zips, hooks, etc), prints, assembly and accessories

Tailor-made Air Ducting&Diffusers

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Examples of applications8.

The first fabric diffusers in history were used in the food industry. Sanitary regulations require that all food processing devices must be easily and completely capable of being cleaned. Out of all the air distribution system options, this condition is only met by textile diffusers/ducting. They are perfectly clean after washing and the disinfecting agent also destroys what resists the antibacterial treatment. Fabrics made of endless fibres, developed specially for the Prihoda‘s textile diffusers, are very smooth and thus do not allow sedimentation of impurities. This distinguishes them from the diffusers made of staple fibres that successively fill with dust and can represent a sanitary risk.

For mainly high halls we can offer an air distribution system through a row of larger holes or nozzles, as required. In any case, accurate air directing and distribution as the customers wish will be possible. Experience from practice confirms that fabric ducting&diffusers in a supermarket is a substantially better (more uniform) air distribution system than traditional systems. In addition, the costs on this are lower. A matter of course is the possibility of various colour versions or different distribution for various zones. For instance, for the cooled and heated section of the supermarket. Fire resistance of our fabrics conforms to the requirements of all world standards.

Food processing industry

Supermarkets and gathering areas

Tailor-made Air Ducting&Diffusers

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Installations at various sport arenas are very typical for fabric ducting&diffusers. For large sports halls is available a wide choice of directed distribution possibilities. On the contrary, cooling air dispersion at minimum speed will not be negatively perceived by fitness centre visitors. There are often low rooms where air distribution is always difficult. Semicircular fabric diffusers on a ceiling are the best solution in terms of both price and function. Installation of fabric diffusers in swimming pool environments is almost given. The fabrics used, including installation material, are fully resistant to damp environment. Combination of different colours revives interior.

In large stockrooms fabric air distri-bution systems provide uniform air distribution, thus ensuring mainte-nance of stable temperatures. This is usually the essential requirement for storage of foodstuffs. If people have to work in an environment with low temperature, then they are usu-ally very sensitive to draught. Incon-venient air distribution might cause higher sickness rate. Fabric diffu-sers disperse air without causing draughts, and create an acceptable climate.

Fabric air distribution are a perfect solution for any industrial branch. They provide uniform (draughtle-ss) air distribution at unbeatably low costs, or enable directing of air per end user’s request. Over 100 hanging alternatives provide make it possible to choose a convenient solution for any situation, taking in consideration the construction of ceiling and other installation in the given production plant. Contamina-ted environments require the use of fabrics with larger holes (perforati-ons, not microperforations).

Food stores, low temperature worksites

Chemical, textile and and electronic industry

Pools, sports halls and fitness centres

Tailor-made Air Ducting&Diffusers

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Space in kitchens is usually narrow, and their extreme load with heat and vapours requires highly intense ventilation. Fabric diffuser disperses air uniformly, without creating draughts. Any directing of airflows is usually totally useless. The material used is resistant to vapours and its maintenance is (also thanks to small dimensions and low weight) very easy. Comparing the prices of stainless ceiling, the costs of our solution are much lower! Use of non-fabric distribution systems fails the requirement on ease and perfect cleaning that is necessary for sanitary reasons.

Higher aesthetical demands can be satisfied by colourful and shape variability of fabric air distribution. Correctly manufactured and perfectly installed fabric diffusers become an elegant part of an interior. Air dispersion when using fabric distribution systems functionally equals cooling ceilings or beams. Comparing to those solutions, the price difference is huge even in best equipped fabric diffuser. Unlike the traditional diffusers, embedded in soffits, our solution does not cause any local heat discomfort. Experience has demonstrated that employees in such equally distributed and cooled offices are significantly more satisfied.

The benefits of using fabric distribution systems for cooling or heating of large scale tents or other temperature structures are entirely clear. A light roof structure can easily bear fabric ducting and diffusers weighing from 100 to 400 g/m². Assembly is very quick, using supporting wires and hooks stitched onto the diffusers. Top quality material allows multiple repeated use. Cooling (heating) by means of a single larger source with connected fabric air distribution system is much more economical than just cold (heat) blowing into a space. In case of heating without air distribution system the flow is bent upwards and the zone under the ceiling gets overheated which results in enormous heat loss. In cooling, intense airflow causes local undercooling and draughts; on the other hand, insufficiently cooled zones are created elsewhere. Both cases are successfully resolved by a properly designed fabric air distribution system.

Kitchens

Offices, restaurants, cinemas etc.

Temporary installations

Tailor-made Air Ducting&Diffusers

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9.

Tailor-made Air Ducting&Diffusers

Frequently asked questions

PŘÍHODA s.r.o. were the first worldwide to introduce negative pressure ducting on the market. It is made with square or triangular shape. The principal is based on sufficient stretching of all ducting walls by means of tensioning system. The construction enables simple disassembly and re-installation. Perforation is used for air inlet in the ducting.

This is not a short term solution. Diffusers made from good quality fabrics will last for fifteen years or longer. Light fabrics (approx. 100 g/m2) with maximum permitted number of 50 washing procedure or the cheap, (usually polyethylene foils susceptible to tearing) may have limited durability.

In a well designed diffuser which does not utilise shaped pieces there is an almost constant static pressure throughout. The fabric perforation is calculated based on the average value of the static pressure. In other words, the diffuser is designed based on the fan‘s external pressure to which it is adapted. Shaped pieces and turbulence equalisers present certain pressure loss which needs to be taken into consideration. Loss caused by friction is usually minimal due to the decreasing air speed inside the diffuser. The minimum utilisable pressure is 50 Pa, with light materials 20 Pa.

Diffusers with micro-perforation and even diffusers with larger holes never get completely clogged by contamination (if used with minimum pre-filtration EU3). The maintenance (typically washing in a washing machine) is therefore necessary for hygienic and aesthetic reasons only. Each individual piece separable by a zipper contains a washing-instruction tag which contains sufficient instruction for washing. Our experience has proven that our fabrics made of endless fibres remain internally almost clean even after many years of operation.

1/ What does a textile diffuser look like when the fan is switched off?

single suspension double suspensionsingle suspension

with arcssingle suspension

with tyres

inflated without air supply

Circular diffuser - comparison of installation

more in chap. 5.8.

2/ Is it possible to use fabric ducting for exhaustion of the air? more in chap. 1.3. , 5.2.

3/ What is the service-life duration of fabric diffusers?

4/ What is the pressure loss of a fabric diffuser? more in chap. 2.3.

5/ What to do with diffusers when they get clogged by contamination? more in chap. 7.

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Tailor-made Air Ducting&Diffusers

Mould can form on any kind of material if it is moist and unventilated. This goes for fabrics with antibacterial treatment, too. It is caused by the fact that moulds are not bacteria. Therefore, never store moist diffusers packed-up or do not let them out of operation for long periods of time. Moulds cannot be removed from fabrics by any means.

PŘÍHODA s.r.o. has developed a special construction which enables to use quadrangular cross-section. The principal is based on stretching the fabric in transverse and longitudinal direction by means of tensioning system. The construction enables simple disassembly and re-installation. Fabric ducting with quadrangular cross-section can be assembled directly on the ceiling or suspend in the area.

If permeable materials are used, the fabric functions as a filter for the part of the transferred air that goes through the fabric. As the fabric contamination gradually increases, the pressure loss grows and the air flow decreases. Therefore, it is necessary to wash the fabric. We consider the utilisation of perforated fabric to be by far the best solution. Although perforated fabrics do not function as filters they do not change the pressure loss value and the number of necessary washing procedures significantly drops. We are a manufacturer of distribution (not filtering) elements.

Use of plastic nozzles or longitudinal slots of sieve can be explained on historical basis. These tools used to enable directing of certain airflow, the nozzles in addition stiffened the burred margins of the holes. When they began to use laser technology that allows cutting of accurate holes with sealed margins, their utilization became useless. Rightly designed rows of holes fulfil the same purpose, whilst being cheaper and nicer. This is the reason why Prihoda s.r.o. need not use either slots or plastic nozzles and yet achieves the same air distribution.

We use permeable materials to avoid condensation in air distribution with temperature below the dew point of environment. However, we only have material of a single permeability value. It is very low and serves just to prevent condensation. For air distribution we use exclusively holes (perforation or microperforation or a combination of these). Our product portfolio includes also impermeable materials, use of which is often unavoidable.

6/ Can fabric diffusers get mouldy?

7/ Is it possible to use quadrangular diffusers? more in chap. 2.1., 5.2.

8/ Does the textile diffuser function as a filter at the same time?

9/ Why PRIHODA does not use plastic nozzles or slots?

10/ Why PRIHODA does not use more permeable fabrics?

microperforation perforation

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5+5+510.

Tailor-made Air Ducting&Diffusers

5/ Aesthetics Various colour and shape combinations may satisfy the needs of an architect and the product then becomes a tasteful part of the building interior.

5/ Antistatic design The interwoven carbon fibres make our PMI, NMI and NMR textiles more electrically conductive. The voltage between the tubing and the ground is thus zero when properly grounded.

5+5+55 for fabric ducting&diffusers

5 for PRIHODA`s fabrics

1/ Economy, speedCost saving compared to sheet metal system may reach as much as 70%! Take the price of conventional diffusers, transport, installation, setting of the proper air flow, and cost of cleaning into consideration! Assembly and disassembly only take a fragment of time that is needed for the traditional heavy systems!

2/ Hygiene After washing and disinfecting, as necessary, the entire system is 100% clean and bacteria-free! Such a guarantee cannot be achieved with traditional material.

3/ Ecology Fabric air ducting&diffusers are environmentally-friendly beginning with their decreased energy demand for transport and installation. They are partially manufactured of recycled material, upon request we can arrange return withdrawal of old components.4/ Method Layout of distribution openings is optional and so is their size. An inexhaustible number of air distribution methods can be achieved beginning from draught-free diffusion up to targeted transfer over a long distance!

1/ Optimum strength Through long-term development, we optimized the mass of our textiles to approxima-tely 200 to 220 g. The textile strength moderately exceeds the seam strength, which is ideal. Greater strength of heavier materials does not in any way benefit customers since the strength of a product is limited by the strength of the seams.

2/ Negligible outlet of particlesDue to using endless fibres, all our fabrics can be used in the so-called clean rooms up to the class 4. Laboratory tests demonstrated almost zero outlet of particles from materials in operation. Our fabrics are very flat and do not allow settlement of impurities from flowing air. This air is distributed through the holes, and the textile diffusers remain nearly clean inside (in a normal environment). They do not require other maintenance than outer dusting. Thanks to endless fibres, the appearance of the fabric does not change even after many washing cycles, unlike materials made of staple fibres.

3/ Antibacterial effect Special treatment guarantees killing of bacteria that are settled in the fabric. This effect does not vanish even after multiple washing. After ten washing cycles it still conforms to the requirements of relevant standard which means almost a lifetime effect, considering low frequency of washing. This applies to PMI/NMI/NMR fabrics.

4/ High fire resistance The PMI/NMI/NMR fabrics are certified according to EN 13501-1 with an excellent result. They achieve classification in B-s1,d0 class. They far exceeded the require-ments of UL 723 norms in the U.S. Our range of products includes class A2 - textiles made from fibre glass.

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5/ Speed We are able to reach the shortest delivery term even in hard conditions of custom manufacturing, all that because of excellent organization of work. In 2012, we delivered roughly 4500 orders into 56 countries across the globe. More than 99% of these deliveries were dispatched within our confirmed terms. The term of delivery in order-based production did not exceed 3 weeks throughout the year; a range of orders was produced within an express term of 1 week.

5 for PRIHODA

1/ Best rate price / quality We offer the best rate of price and quality in a long-term view. Our very reasonable prices do not mean any compromise on quality. We hold ourselves responsible for the products we deliver, their proper function and long service life are the priority for us.

2/ Experience & knowledge, technical support We only manufacture this product and focus constantly in its improvement. Our engineers verify carefully every technical detail in our specialized test room. Every delivery consists of calculation of technical parameters, inclu-ding pattern of airflows.

3/ Innovations Every year we launch several novelties on the market as a fully natural consequence of the enthusiasm of creative skills of our people. We do not consider anything finished, everything can still be improved. For example microperforation of fabrics, which start to use more and more producers, is our unique technology.

4/ Long warranty period Because of the highest quality we are able to provide a ten-year warranty.

PŘÍHODA s.r.o.Za Radnicí 476

539 01 HlinskoEU - Czechia

tel.: +420 469 311 856fax: +450 469 311 857

[email protected]

12/2012