Up ] NRV ] FTV ] BFV ] [ HGC ] WCV ]

 

NORMEX Hydrodynamic Guided Closing (HGC)

 

Fine application difference of check valves compelled Normex to come up with a new check Valve design named as Hydrodynamic Guided Closing (HGC). The closing mechanism in guided and backed with return spring for quick closing. This valve has inherent ability to arrest water hammer. Normex has succeeded in keeping very low pressure losses in this valve also.

 

 

n Low pressure drop (Hydrodynamic)

n Perfect sealing (Guided closing)

n Eliminates water hammer

n Can work vertically, horizontally or angular

n Compact Size, Silent Operation

          

 

HGC Non-Return Valves

 

 

Principle :

When the pump starts, the disc moves upward and the specially designed profile of the disk and body gives passage to the liquid / air without causing change in its velocity. This gives the aero / hydro dynamic effect, which results in minimum pressure drop (See fig.). When the pump stops, the disc moves backward quickly (Mouse over  fig.). Because of long axial guide there is no displacement of the disc while closing. This & the concentric machining results in perfect sealing. In addition, as the valve is closed before the back flow starts, the problem of water hammering is eliminated.

 

Dimensions

 

Size(A) (mm) D W H
40 150 85 85
50 165 105 100
65 185 128 120
80 200 156 140
100 220 194 170
150 285 264 230
200 340 346 290
250 406 430 355
300 457 500 398
350 527 600 475
400 578 686 560

 

 

 

     

 

 

 

 

Part List / Materials of Construction

 

Part

Description

Standard

Special

1

Body

Cast Iron

Cast Steel / St. Steel

2

Closing disc

S. G. Iron

Cast Steel / St. Steel

3

Guide

Cast Iron

Cast Steel / St. Steel

4

Sealing ring

Nitrile Rubber

Neoprene, Viton, Teflon etc.

5

Seat ring

L. T. Bronze

St. Steel / Teflon (PTFE)

6

Guide brush

L. T. Bronze

St. Steel / Teflon (PTFE)

 

Pressure rating

Size  150 - 300 mm = PN 16

                 350 mm = PN 16

Body test : 1.5 times rated Pressure

Seat test  : 1.1 times rated Pressure

 

Technical Comparison

 

Check valve - Hydrodynamic Guided Closing (HGC)

&

Conventionally used Flap type

Normex HGC model H-01

Conventional Flap type

Innovative design, focused to eliminate all constraints of conventional one and offer optimum performance

Conventional design carries lot of constraints.

Internals designed in such a way that laminar flow is not disturbed to a large extent.

Turbulance is generated in fluid flow due to design limitations.

Very low pressure drop acros the valve which saves energy, reduces pump cycle time duration

Comparatively high pressure losses, requires more energy increases pump cycle time duration.

Valve closing mechanism is guided by precise guide & plunger mechanism which ensures perfect sealing.

Hing-pin-disc closing mechanism has lot of play which results in leakages.

Closing mechanism supported by spring force eliminates hammer to a large extent.

Closing mechanism is by back force of fluid hence maximum effect of hammer which causes many a times damage of pump or bursting of pipes.

Compact space saving design. Reduces face-to-face length. Light weight hence easy handling.

Standard full length valve higher in weight.

Vertical or horizontal installation is easily possible.

Installation recommended for horizontal position.

Symmetrically shaped design hence no top or bottom side selection for installation.

Cover side should be always on top for installation.

Material used is of grade FG 260 having higher tensile strength (26 N/mm2)

Material recommended is FG 200 having lower tensile strength (20 N/mm2)

For more details contact Normex.

 
Up ] NRV ] FTV ] BFV ] [ HGC ] WCV ]