Presentation on theme: "MBB box When performance matters…. Secure, Flexible and Simple."— Presentation transcript:
1 MBB boxWhen performance matters….Secure, Flexible and Simple
2 Background...An independent Swedish report shows generally low accuracy on flow-measurement of plenum boxes in the ventilation marketQuotes from the report:“For ceiling diffusers with plenum box we have found that the distance to disturbing source often has larger impact for calculation of air flow than the suppliers indicates. Even the position of the damper often has influence but that is not mentioned in the suppliers instructions for calculations of air flow... We request that suppliers correct the majority of K-values and improve the documentation and labelling”.“If a diffuser has more K-values it provides substantially better opportunities to get correct measuring results”.This we had to take seriously
3 Background... Why plenum box? The box shall be; Balance ventilation systemMeasure air flowReduce noiseEven distribution to diffusersThe box shall be;QuietAccurateSmallSimpleReadable
4 Balancing principles... 1. Rotating 2. Sliding 3. Linear Must be perforated for noise“Only fine-tuning”2. Sliding3. Linear4. Linear cone“0”-100 % air flowLinear characteristicsLow noiseDotted Line = old MBA
5 Measuring principles 1. Before the damper 2. Over the damper Sensitive to bends or installationPoor in low flow range2. Over the damperVariable k-value3. After the damperMore pressure dropVariable k-value for high accuracy4. Over the diffuserNot for high flow rate diffusersDifferent k-values for diffusers
6 Air distribution principles... 1. Damper coneNeeds a certain widthNo extra equipment2. Closed perforated plateMore pressure drop3. Open perforated plate.
7 Secure... High capacity and low sound even at high pressure CFD-, and laboratory testedCompletely unique damper solutionSmaller boxUsable in systems with chilled beams.
8 Secure... High capacity and low sound even at high pressure = Capacity of NS19+MBBExample: Competitor 1 and 2 can manage about 45l/s on a 125mm connection.Lindab about 58 l/s.Competitor 1Competitor 2=Preconditions: 100Pa and sound power level 34dB(A)(Enquiry from main customer)
9 Secure... Money saving A traditional system of 40 diffusers Dampers and silencers38 dB(A)Total cost SEKExchange MBA with MBB32 dB(A)Similar costOKCost material:Box MBA-125/160, 40 pcs.Damper, DRU 315, 4 pcs.Silencers, LRCA , 4 pcs.Damper DRU 125, 4 x 5 pcs.Silencer SLCU , 4 x 5 pcs. = 20 pcs.Connection ducts dim 125, length 3 m, 40 pcs.Total: 42,100 SEK (netto)Cost mounting:Total: 52 hours, approx. 18,000 SEK
10 Secure... Money saving Remove Silencers Remove Dampers 34 dB(A) Total Cost SEKGo down one size+ 7 pa – approx. 1,6 % higher energy consumptionStill below 38 dB(A)Total Cost SEKSavings of appr. 37%.Cost material:Box MBB-100/160, 40 pcs.Connection ducts dim 100, length 3 m, 40 pcs.Total: 24,500 SEK (netto)Cost mounting:Total: 38 hours, approx. 13,300 SEK
11 Flexible... 0-100% operational area Possible to have low flow with high pressure20 l/s, 100 Pa LWA= 24 dB(A)And high flow with low noise76 l/s, 70 Pa LWA=34 dB(A)With 125mm connection!!!!
12 Flexible... Viable for future applications The MBB box can cope with almost any future demandsAlways possible to balance it to a lower flowTogether with e.g. LKP/LCP you make sure to have unique operating range all the way down to zero also concerning air movementsVery high damping without generating a noise problem
13 Simple... Simplifying balancing Damper with readable k-values Easy to reach and read the scaleK-values fixed to damper positionsK-values are independent of diffusersCan be pre- and re-balanced (CADvent)Steady high measuring pressure even at low flowBetter adjustment characteristics (No “Ketchup effect”)100%50%
14 Simple... Small dimensions Easy handling, mounting and cleaning Smaller ducts because of larger capacityLower Carbon footprint (Less material, less transports, less packaging material)Easy installing with Safe / Safe Click connectionLow building heightInsulation prevents sound generating from outlet (Inlet diffuser increases sound otherwise)DimensionLindabComp. 1Comp. 2100/125Height160 mm180 mm220 mm240 mm255 mm310 mm340 mm345 mm
15 MBB box When performance matters... Secure Flexible Simple Low sound – high pressureLess dampers and silencers – still silentAccurate measurement – no problem with disturbing sources before the boxReliable measurement – variable k-valuesFlexible0-100% dynamic operational areaLow flow with high pressureHigh flow with low noiseViable for future system changesSimpleLinear damper means easy and quick balancingPrebalancing is possibleSmall dimensions – easy to handle and installEasy to clean