Elliptic diaphragm control valve

VACOMASS® elliptic diaphragm control valve

• Diaphragm control valve with elliptical control aperture and falling flow axis
• Optimized for high airflow volumes at low pressure loss
• Low operating noise due to integrated pressure wave breaker (patent pending)
• 0-100% control span, bubble-tight in closed position
• Electric actuator for sensitive aeration control is standard feature
• Valve optimized for minute control steps of less than 0.2% of flow

VACOMASS® elliptic diaphragm control valve

The VACOMASS® elliptic diaphragm control valve is a technically optimized diaphragm control valve with an elliptical aperture for precise, lowpressureloss control and distribution of aeration air in wastewater treatment plants. It closes bubble-tight. For sensitive control of axial and tangential flows (e.g. after elbows) the flow axis moves downward and is designed for compliance with DIN EN 60534-2-3.

The diaphragm control valve has a stable, apertureproportional control curve in the usual control range and can be positioned from 0-100% open. Differential pressure loss, as measured according to ATV guidelines, less than 10 mbar (0.145 psi) at specified flow and 100% open.

The diaphragm control valve body consists of two identical halves that are designed for use as a wafer valve or end-of-pipe. A groove between the body halves holds the seal. The prismatic PTFE/carbon seal seals the diaphragm and simultaneously acts as a guide for the diaphragm. The pairing of the stainless diaphragm plate with the PTFE/carbon seal provides a vibration-free guide and prevents jamming.

Important features include:

• Bubble-tight shut-off for applications such as swing zones and process optimization – saves a separate automatic isolation valve and associated costs
• Sizing based on customer airflow rates; specification of the valve size is targeted towards optimal performance at average flow rates.
• At 100% the entire pipe cross section is open, reducing pressure losses
• Due to the shape of the control diaphragm, the control range for airflows is much greater than comparable triangular, square, pentagonal or hexagonal diaphragms
• Designed with falling flow axis to direct flow towards the wall. This supports pressure recovery for a relatively low pressure loss – saves energy costs
• Pipes must be reduced/expanded for measurement and control to achieve optimal performance.
• The diaphragm control valve is designed and built with a stainless steel diaphragm plate and seals made of Teflon/carbon/Viton for environmental and media temperatures up to 1500C (3000F), selflubricating spindle for dry operation, and hermetic sealing of the spindle against moisture and dust – reduces operations and maintenance costs
• Comes with a VACOMASS electric actuator for sensitive control of air from -400C to +600C (-400F to 1400F) (optionally up to +800C/+1750F), flanged directly to the valve; besides AUMA and Rotork other manufacturers are available as long as they meet technical specifications
• Can be combined with a VACOMASS flow meter for aeration control
• Despite space needed for pipe reduction/expansion, special calibration of the flow meter for compact installation provides a relatively short measurement and control section – ideal for upgrading existing installations.