Butterfly Valve

DENZ Water B13 Combined Butterfly check valves prevent reverse fluid flow in a variety of applications. The seating arrangement of these valves is similar to that of butterfly valves. The flow characteristics of butterfly check valves are similar to those of butterfly valves. Because of this, these valves are often used in piping systems with butterfly valves. By using the principle of pressure difference, butterfly check valves operate automatically. The valve disc opens when the suction pressure exceeds the outlet pressure. When the suction pressure drops, when there is backflow, or when the pump stops, the valve closes. Butterfly check valves prevent fluid from flowing backwards. Especially in water supply and food applications, reverse fluid flow can contaminate the fluid. Also, reverse fluid flow can cause damage to piping equipment like pumps. The basic structure of the overspeed safety valve is guaranteed by a robust construction and using materials tested in laboratories in the most adverse conditions. The valve is actuated by a dynamic oil actuator laterally flanged on the valve, consisting of a hydraulic cylinder for opening, and provided with a counterweight to guarantee automatic closing in the event of excessive driving speed. Optionally, the safety valve can be reset by means of an electrical control unit that allows the valve arm to be repositioned in the normal position. The set is made up of the following elements: • Double eccentricity butterfly valve. • Speed detector. • Hydraulic reset unit (different types • depending on model). • Electrical control panel (optional depending on the model). • Auxiliary elements. • There are different solutions for the speed detector depending on several criteria (accuracy, reliability, independence from power supply, etc.

• Body formed by double eccentricity butterfly valve (DENZ B10).

• Setpoint speed (maximum allowed flow) adjustable on the detector.

• Possibility of autonomously carrying out at least one complete maneuver (automatic closing, reset - preparation for a new closing).

• Closing by “shot” (controlled by the speed detector) of the counterweight, which makes a gradual movement to ensure complete closing even under the most severe conditions.

• Valve reset by hydraulic oil cylinder. • DENZ B13 Butterfly Check Valves can be used as control valves and for regulation purpose.

• ENGJS500-7 Ductile iron body and bonnet for high strength and impact resistance.

• Possibility of manual emergency control and possibility of closing modulation at speeds

• As a default, the sealing ring on the disc is EPDM. Various options are available, including NBR and VITON. • Double eccentric / double offset disc design prolongs the life cycle of the sealing and the valve. • A welding seat made of SS308 LSI grade stainless steel is manufactured on the body using automatic welding

machines and microfinished precision milling. The disc sealing ring applies equal pressure to all points of the welding seat once the disc is fully closed.

• Due to the double shaft design, pressure loss is minimized, and energy efficiency is increased. • The disc sealing ring applies equal pressure to all points on the welding seat when the disc is fully closed.

Drop-tight closure.

• Double O-ring feature on both shafts ensures high sealing. • The shafts are equipped with corrosion-resistant bronze bushings. • Maintenance free bronze shaft bearings • Additional limit switches can be adapted for hydraulic systems • Programmable Logic Controllers (PLC) and electric panels can be installed on or with the valve. • Drop-tight sealing is extended with a solid/one-piece block molded T-shaped disc sealing ring. • The counter lever length and weight can be adjusted to adjust the speed of the open/close. • The disc sealing ring applies equal pressure to all points on the welding seat when the disc is fully closed. • Internal and external coatings with an average thickness of 250 microns are applied to the disc and body. Depending on the application, higher coating thicknesses can be applied.

• Coatings that meet WRAS hygienic standards are available upon request. • Low torque requirements during operation. • A balanced position of lifting holes on the body makes transportation and installation easier. • 100% of the valves are subjected to Hydrostatic tests according to EN 12266-1. Pressure for seat: PN x 1.1 , for

shell: PN x 1.5