Abstract: A ventilation system is disclosed comprising a main duct (101) connected to at least one motorized fan (105), and further connected to at least one workplace (Wa; Wb; Wc) via a local duct arrangement (102a; 102b; 102c). The local duct arrangement comprises an asymmetrical bend duct section (106). A first and a second pressure sensor (120,122) are arranged on different positions on the outside of the bend duct section and in communication with the interior thereof. The pressure sensors are configured to communicate with a control computer (200) configured to determine a pressure difference between the positions of the sensors and to control the speed of the fan. Further, a method of operating a ventilation system is disclosed and also an asymmetric bend duct section and the use thereof.

Abstract: A ventilation system is disclosed comprising a main duct (101) connected to at least one motorized fan (105), and further connected to at least one workplace (Wa; Wb; Wc) via a local duct arrangement (102a; 102b; 102c). The local duct arrangement comprises an asymmetrical bend duct section (106). A first and a second pressure sensor (120,122) are arranged on different positions on the outside of the bend duct section and in communication with the interior thereof. The pressure sensors are configured to communicate with a control computer (200) configured to determine a pressure difference between the positions of the sensors and to control the speed of the fan. Further, a method of operating a ventilation system is disclosed and also an asymmetric bend duct section and the use thereof.

Abstract: A back pressure flap valve arrangement is disclosed. The arrangement comprises a housing (101) having an inlet opening (102) and an outlet opening (103) adapted for connection of the housing (101) to a ducting (200), and at least one side wall (104) extending along a flow direction through the housing (101) from the inlet opening (102) to the outlet opening (103). A flap (1) is pivotably hinged about a shaft (5) thereby being movable between an open position and a closed position, said shaft (5) extending transverse the flow direction. At least one locking device (10) is fixedly mounted to the side wall (104) and comprises a locking pin (14) and a stopping member (12). The locking pin (14) is movable between a retracted position and a locking position, and being biased towards said locking position.

Abstract: A back pressure flap valve arrangement is disclosed. The arrangement comprises a housing (101) having an inlet opening (102) and an outlet opening (103) adapted for connection of the housing (101) to a ducting (200), and at least one side wall (104) extending along a flow direction through the housing (101) from the inlet opening (102) to the outlet opening (103). A flap (1) is pivotably hinged about a shaft (5) thereby being movable between an open position and a closed position, said shaft (5) extending transverse the flow direction. At least one locking device (10) is fixedly mounted to the side wall (104) and comprises a locking pin (14) and a stopping member (12). The locking pin (14) is movable between a retracted position and a locking position, and being biased towards said locking position.

Abstract: Described are embodiments of a safety arrangement for a fluid piping system with a check flap associated with the piping system, where said check flap enables a medium to flow in the piping in an unblocked direction from an area onto which flow occurs into an area off of which flow occurs and where in a blocking position said check flap counteracts flow in a blocked direction opposite to the unblocked direction by abutting a sealing face of the piping system, characterized in that in the rest position of the sealing face when there is no flow in the piping system the check flap is at a distance from the sealing face and starting from the rest position only comes to abut the sealing face on the application of pressure in the blocked direction.

Abstract: The invention relates to a device for cleaning the filter surface of a filter element, through which the liquid to be filtered flows, during a filtration operation using a pressurised cleaning fluid. According to an improvement of the invention, a distribution device is provided which delivers an essentially even pressure distribution of the cleaning fluid over the entire area of the filter surface to be cleaned.

Abstract: A device for tearing-up and stoking straw into a burner unit. A reciprocating slide is provided under a magazine shaft for straw bales, the slide having mutually staggered teeth on its upper side in a forward part of the slide and elongated fins extending in the direction of movement of the slide in a rear part. The part closest to the stoking channel constitutes a piston means for the conveyance and compression of comminuted straw. The straw is torn-up during the initial advance movement of the slide towards the channel because the teeth are in engagement with the bottom of the lowermost bale, whereas the bale is upheld by the teeth and the fins during the return movement of the slide. The piston means ensures that the shredded straw is pushed into a stoking channel for the combustion chamber of a boiler. Very compressed straw bales are thereby very uniformly comminuted and compressed before being fed into a burner unit.