Pietro Fiorentini ■ Dival 507/512 Pressure Regulators

Classification and Range of use The Dival 507/512 is a downstream direct-acting pressure regulator with balanced plug, for low, medium and high pressures. Suitable for previously filtered, gaseous, non-corrosive liquids; thanks to the concept of a balanced plug, you can achieve a high flow rate coefficient, highly accurate (even at maximum flow rates), a lock up zone and relatively low lock up pressure, no internal leakage at zero flow rate and reduced response times. The constancy of the regulated pressure and its accuracy, even with significant changes in the upstream pressure and/or flow rate,...

Pietro Fiorentini FEATURES Operating Features

The Dival 507/512 has been designed with a high degree of modularity for incorporating alternative devices and accessories in the basic version. SHUT-OFF DEVICE model LA/... This is a Safety Accessory that intercepts the gas flow when there are abnormal pressure conditions compared to that set during calibration of the dedicated pressure switch device. Calibration can be varied at will, according to the operating requirements, within the ranges on the table below, depending on the pressure switch model provided. For safety reasons the shut-off device can only be reset manually and inside the...

INCORPORATED RELIEF VALVE The Dival 507/512 series can be equipped with an incorporated relief valve that discharges the gas into the atmosphere when the regulator outlet pressure exceeds the set value. The events that can lead to the valve opening are: ¢¢ thermal expansion of the downstream gas in the absence of flow. ¢¢ pressure peaks caused by the downstream valve rapidly closing (in the event of small volumes). When the outlet pressure returns to below the set value, the relief valve closes again.

The MONITOR is a safety accessory that performs the functions of the service regulator when the main regulator fails. This is a regulator valve that is usually fully open during normal operation of the service regulator. The MONITOR is an emergency pressure regulator that is usually upstream, in the direction of the gas flow, of another pressure regulator that performs the function of a SERVICE regulator. So that a Dival 507/512 regulator can perform the MONITOR function, restriction of the internal pressure tap and activation of only an external pressure tap must be foreseen.

Pietro Fiorentini Control heads The pressure ranges are determined by the control heads. The table below summarises the heads available and the obtainable regulated pressure ranges in mbar. The obtainable pressure ranges are in mbar The regulator is usually chosen on the basis of the flow rate calculation determined through use of the flow rate coefficients (Cg or KG), as indicated by Standard EN 334. However, the analytical calculation method does not correctly size the regulator as the obtainable theoretical flow rate should not be considered, but only a percentage of it, which is variable...

TYPICAL CONNECTION DIAGRAMS The following examples are provided as a recommendation to get the best performance from the Dival 507/512 regulator. IN-LINE INSTALLATION Regolatore Regulator Presa d’impulso esterna External sensing line Manometer Manometro Pressure relief valve Valvola di sfiato 2 x DN I Valvola valve Shut-offdi intercettazione ANGLE INSTALLATION Regolatore Regulator Pressure relief valve Valvola di sfiato Manometro Manometer Presa d’impulso esterna External sensing line Valvola di Shut-off valve intercettazione The Regulator can have: ¢¢ internal sensing line ¢¢ internal + external...

RECOMMENDED INSTALLATIONS Basic position Vertical installation

Pietro Fiorentini Dival 507/512 DIMENSIONS + LA

The data are not binding. We reserve the right to make changes without prior notice.