Unions for straight seamed ducts – airtightness class atc 2 (D)
UNIONS FOR STRAIGHT SEAMED DUCTS
New exclusive design ideal for installations of industrial extractions of solid residue carry-over (textiles, wood, paper, etc), executed with straight seamed ducts with a 7 mm folded lip.
They are manufactured in Galvanized Steel DX51 D + Z 275 MA from Ø 100 mm to Ø 1000 mm.
The joint is made by the combination of 2 components: an inverted steel “V” with its closure system (screw or latch fitting) and a M-1 rubber o-ring. This ensures a high airtightness Class D that equals level D. Standard execution is carried out with screw closure M-6 / M-8. Optionally with a latch fitting closure (with 2 types of safety seals: disposable plastic or reusable in metal).
Splicing and sealing in ultrafast construction “without tools” (latch fitting closure). Easy and quick disassembly for the facilities maintenance and cleaning. Maximum reliability in the union. High finish level.
Simplicity, practicality and economy merge to give rise to a product with the best quality / price ratio in the market.
Patented product totally designed and manufactured in Spain.
We also manufacture special executions in STAINLESS STEEL AISI 304/316 or with ceramic joint M-0 for high temperatures.
Since the manufacture of the straight seamed duct allows small variations of measurement according to the used manufacturing process, we recommend them to be made according to the following sketch so that they fit perfectly to the diameters of our joining flanges and prevent protrusions on the welding zone of the lip (check out photo below):
MESUREMENTS
Measurements for the construction of the duct.


Avoid protrusions on the 7 mm lip. Anomalies such as those in the following photo cause leaks:


ASSEMBLY PROCESS OF THE STRAIGHT SEAMED DUCT UNION
The improvement of this product to achieve a better seal determines that we supply it in two pieces: the “V” rubber gasket prepared as an o-ring piece and the closure “V”.
First, the closure “V” is placed on the assembled section of duct and also the rubber gasket with the “V” facing outwards and near the flange at its end:
la junta “V” de goma preparada como pieza tórica


Next, we make the two lips of the ducts to be joined to exactly match:


Continuedly, the rubber gasket is turned over the two lips with the “V” inwards:


And, lastly, the “V” is mounted on the rubber to then fix the closure to the desired pressure (maximum tightening pair 3 Nm):


Leakage test of Class ATC 2 (D) with three 200 mm diameter joints:


Detail of the airtightness level reached that oscillates between ATC 1 and ATC 2:


Worst rapport obtained in which ATC Class 2 (D) is guaranteed:


CLOSURE FLANGE RINGS WITH BRIMS FOR STRAIGHT SEAMED DUCTS JOINT M1 – FROM Ø 100 mm TO Ø 450 mm
LASTEST NOVELTY !!! Reinforced design in one single size from Ø 100 mm to Ø 450 mm. Two models of closure available on the flanges for straight seamed ducts: screw and latch fitting. Nicer aesthetic finish suitable for exposed installations.


IMAGE GALLERY OF EXAMPLES IN VARIOUS INSTALLATIONS WITH STRAIGHT SEAMED TUBE
Several examples of extraction and ventilation installations of straight seamed duct joined by the RAMI-SYSTEM® closure flange rings with rubber gasket:
Photos of the installations seen in this section have been provided courtesy of MUNTATGES AIRGES, S.L.