TEK Acoustic RABC 1 - Attenuators — Rectangular Attenuator - Type R

TEK Acoustic RABC 2 - Attenuators — Bend Attenuator - Type A

TEK Acoustic RABC 3 - Attenuators — Bend Attenuator - Type B

TEK Acoustic RABC 4 - Attenuators — Circular Attenuator - Type C

Attenuators Rectangle / Bend / Circular

Type R / A & B / C

The well established range of TEK rectangular attenuators is designed to give the building services industry a practical product for all situations. They have all been researched and designed by a leading independent acoustic consultant and tested to BS 4718 1971.

All TEK products are designed in-house by engineers with many years’ experience. This means that we are not restricted to standard sizes and attenuators can be tailor-made to meet your requirements. Our acoustic design service is available to ensure that you receive the best possible advice at the planning stage, thereby avoiding site problems later on.

Rectangular Attenuator

Construction

Casing & Splitters:

The outer casing is constructed from pre-galvanised steel sheet having a minimum thickness of 1.0mm up to a maximum width and height of 1200mm and a minimum thickness of 1.2mm over 1200mm.
Pittsburgh longitudinal joints are used as standard, all in accordance with current HVCA specification.
Splitters comprise an acoustic infill. retained behind perforated or expanded galvanised steel sheet, having a minimum thickness of 0.7mm. The splitters are contained within galvanised 1.0mm sheet steel channels.
Inlet fairings are riveted to the front of each splitter to lower the pressure drop across the attenuators. The splitters are fixed to the attenuator casing with sealed rivets. Half width splitters are fixed to each side wall of the casing to provide sidelinings.

Connections

Rolled angle steel red leaded flanges which are fixed to the casing with sealed rivets. Casings are returned 12mm over end flanges.
Slide-on flange connections as detailed in HVCA specification DW142, figure 41, suitable for low or high velocity systems. Gaskets, cleats and matching flanges normally supplied by others.
Plain spigot ends.

Notations

The notation for a standard rectangular attenuator is type RCP. The prefix R and suffix P are as indicated below. the second letter C indicates a standard splitter.

Prefix R: Standard rectangular attenuators.

Prefix S: Splitters only.

Prefix A: Bend attenuators are available, supplied with short cord turning vanes installed in the airways (having horizontal splitters).
Prefix B: As Prefix A with vertical splitters.
Suffix P: Splitter acoustic infill retained behind perforated sheet steel.
Suffix L: Attenuators may be supplied with low loss fairing on the splitter end to lower pressure drop across the attenuator. Acoustic performance of the attenuator will be degraded.

Circular Attenuator

Construction

Casing & Splitters:

The outer casing is constructed from pre-galvanised steel sheet having a minimum thickness of 1.0mm up to a maximum diameter of 1200mm and a minimum thickness of 1.2mm over 1200mm.
Pittsburgh longitudinal joints are used as standard, all in accordance with current HVCA specification.
The casing is lined with acoustic infill, faced with glass fibre tissue, retained behind perforated or expanded galvanised steel not less than 0.7mm thick.
Where required circular pods can be fitted, comprising acoustic infill retained behind perforated, or expanded galvanised steel having a minimum thickness of 0.7mm.
The pods have a cone inlet and flat end on outlet.

Connections

Threaded inserts to match flange drillings of all makes of axial flow fans or specific customer requirements.
Plain spigot ends.

Notations

Prefix C: Standard circular attenuator.
Prefix P: Pod installed in circular attenuator.
Prefix D: This is preceded by a number (normally 1 or 2) indicating the length of a circular attenuator as a multiple of the attenuator internal diameter.

General Specifications

Infill

The infill is inorganic mineral wool or glass fibre rigid slabs with a glass fibre tissue face to limit fibre erosion. The fibre is inert, vermin, rot, and moisture proof, non-combustible and does not support bacteriological growth, packed to a density of not less than 45 kg/m3. The infill has been tested for fire and has a Class spread of flame (as measured to BS476: Part 7: 1971).

Sizes

Attenuators may be supplied in sections for site assembly by others as required, or as advised by Tek. Nuts, bolts and washers to be supplied by others.

Acoustic Performance

The attenuators have been tested in accordance with BS4718 1971 by an independent consultant. The test procedure eliminates effects due to end reflection, directivity, flanking transmission, standing waves and test chamber sound absorption.

Aerodynamic Performance

The attenuators have been tested in accordance with BS4718 1971 by an independent consultant.

Alterations to the standard TEK specification

Where our standard specification does not cover the installation requirements, select the extra features required from the list below. Simply add the suffix to the standard attenuator code e.g. RCPSAT = attenuator for use in saturated atmosphere.

Suffix M: Polyester membrane installed under the perforated metal typically for protection from grease, moisture or oil-laden atmosphere.

Suffix C: Polyester membrane suitable for operating and clean rooms enclosing acoustic infill hermetically, using polyester strip sealant. Acoustic infill retained behind perforated steel sheet or expanded metal hot dipped galvanised after perforation. Attenuators thoroughly cleaned prior to despatch and fitted with sealed end plates.

Suffix PVF: PVF2 anti-corrosion paint may be applied to all internal metal surfaces to offer resistance to corrosive air.

Suffix SAT: Perforated sheet metal or expanded metal retaining the acoustic infill may be supplied hot dipped galvanised after perforation for use in saturated atmosphere. The infill would be encased with a polyester membrane.

Suffix H: High pressure attenuators may be provided constructed in accordance with the recommendations of the HVCA for the construction of rectangular ducts in high velocity air systems.

Suffix S: Crosstalk attenuators may be supplied with spigot connections in lieu of flanges. Attenuator configuration may be selected to customers’ requirements.

Suffix PVC: Plastic attenuators may be supplied for installation in a highly corrosive atmosphere. Attenuator casings and perforated sheet would be manufactured from PVC.

Full Specification

Attenuator Weights / Rectangular – Type RCP

Width mm	Height mm				Length mm
		600	900	1200	1500	1800	2100	2400
300	300	21	27	36	42	49	56	63
300	600	34	42	55	65	75	88	98
600	600	50	66	87	703	118	134	150
600	900	60	87	113	134	155	176	197
600	1200	86	114	140	165	191	217	243
600	1500	105	135	166	196	226	256	286
900	600	69	91	119	141	163	185	207
900	900	88	116	152	180	208	236	264
900	1200	116	151	185	220	255	290	325
900	1500	137	178	219	259	300	341	382
900	1800	158	205	252	299	346	393	440
1200	600	94	122	150	178	207	236	265
1200	900	119	155	191	226	262	298	334
1200	1200	144	188	232	275	319	362	405
1200	1500	170	221	272	323	375	426	477
1200	1800	195	254	313	372	431	490	549
1500	900	143	186	229	273	316	361	406
1500	1200	172	223	278	330	383	436	488
1500	1500	202	263	325	387	449	511	573
1500	1800	231	302	377	443	518	593	754
1800	900	166	217	268	319	370	423	476
1800	1200	200	261	322	384	446	508	570
1800	1500	234	306	378	450	523	596	756
1800	1800	268	350	433	516	600	783	866
1800	2100	301	395	488	582	790	883	976
1800	2400	335	439	543	774	878	982	1086
2100	1800	304	399	494	589	798	893	988
2100	2100	342	449	556	791	898	1005	1112
2100	2400	380	498	618	878	996	1116	1236
2400	2400	425	558	850	983	1116	1408	1541