AL-DK-D
Válvula de haste
- the device is used for automatic venting and breathing of floating roof tanks in the low position of the floating roof
- robust construction and therefore long lifetime
- when converting from operating to maintenance position, the lift pipe must be extended; adjustment is made by means of an adjustment option using a locking pin
- the valve is not flame transmission proof
- depending on requirements, two or four deflagration- and endurance burning-proof atmospheric flame arresters can be installed to ensures flameproof venting of the tank
Função e descrição
PROTEGO® lift-actuated vent valves type AL-DK-D provide automatic venting of floating roof tanks when the floating roof is lowered onto its supports and the tank is either drained or refilled. When the floating roof is in its lowest position, the valve is forced to open through lift actuation, which prevents inadmissible vacuum during final draining or inadmissible pressure during refilling.
Lift-actuated vent valves PROTEGO® AL-DK-D can be combined with atmospherically deflagration-proof and endurance burning-proof vent caps.
The PROTEGO® AL-DK-D valve consists of a housing (1) with a sheet metal panel to be welded onto the floating roof or a flange for mounting on a mating flange, two or four flanged connection nozzles (2) for installation of vent caps, cover (3), lift (4) including valve disc (5), lift pipe (6), and the condensate drain valve (7) which can be designed to be flame transmission proof. The condensate drain is sealed by a flat gasket attached to the valve disk (5). The cover (3) is sealed by a sealing cord (8).
As the lowest position of the floating roof varies for operation and assembly, specify the dimensions h1 and h2:
h1:Distance between the lower edge of the connection of the equipment and the tank bottom at the lowest level of the floating roof in the operating position (operating position with an empty tank).
h2: Distance between the lowest level of the floating roof in the maintenance position and the lowest level of the floating roof in the operating position (operating position with an empty tank).
If the floating roof supports are changed from operating position to maintenance position, the lift has to be extended as well. This is done with an adjustable locking pin that is secured with a split pin.
The valve is not flame transmission proof.
Based on a hazard analysis with regard to material selection and function, the valves have no potential ignition sources. As a result, they are not subject to the European Explosion Protection Directive (ATEX) when used in explosive atmospheres.
Material
| Housing | Steel |
| Valve guide | Stainless Steel |
| Gasket | FPM |
Dados necessários para a especificação
Produto armazenado
Diâmetro do tanque (m)
Altura do tanque (m)
Altura do suporte h1 (posição de operação com tanque vazio)
Altura do suporte h2 (posição de montagem elevada)
Pressão máxima admissível do tanque pT (mbar)
Potência da bomba (m³/h)
Seleção e Desenho
The required quantity and nominal size DN will be defined based on the calculated flow rate from the thermal venting and pumprate in lowest floating roof position (Nm³/h or CFH) and based on the maximum acceptable tank pressure pT (mbar / inch W.C.) according to the flow capacity charts. Special models are available on request.Flow rates and pressure losses of vent caps PROTEGO® EB or PROTEGO® BE/HR-400 have additionally to be taken into account according to the appropriate charts in the relevant data sheetsor operating instructions.
Tipo de conexão flangeada
| EN 1092-1, forma B1 ou DIN 2501, forma C, PN 16 , a patir DN 200 PN 10 | EN ou DIN |
| ASME B16.5 CL 150 R.F. | ASME |
Versão e especificação
Two designs are available:
Vent valve with two connections | AL-DK-D |
Vent valve with four connections | AL-DK-D-4 |
Diagrama de vazão
Este diagrama de vazão foi determinado em uma bancada de medição de vazão calibrada e certificada pela TÜV. A vazão V em m³/h se refere ao estado técnico padrão de ar, conforme ISO 6358 (20°C, 1bar). Para conversão em outras densidades e temperaturas, veja o cap. 1: Bases técnicas.
Lift-actuated vent valves of type PROTEGO® AL-DK-D can be combined with vent caps type PROTEGO® BE/HR-400 or PROTEGO® EB .
