Cases

FAQ

VALVES & FITTINGS



Brass Gate Valves Cast Iron Gate Valves Cast Steel Gate Valves Forged Steel Gate Valves Stainless Steel Gate Valves Rising Stem Gate Valves Non-rising Stem Gate Valves Double Disk Parallel Gas Gate Valves Knife Gate Valves Bellows Sealed Gate Valves

Globe Valves



Cast Iron Globe Valves Cast Steel Globe Valves Forged Steel Globe Valves Stainless Steel Globe Valves Brass Globe Valves

Butterfly Valves



Wafer Type Butterfly Valves Flange Type Butterfly Valves Eccentric Butterfly Valves Lug Type Butterfly Valves

Check Valves



Cast Steel Check Valves Cast Iron Check Valves Stainless Steel Check Valves Brass Check Valves Lift Check Valves Swing Check Valves Forged Steel Check Valves

Ball Valves



Cast Iron Ball Valves Cast Steel Ball Valves Stainless Steel Ball Valves Brass Ball Valves Fully Welded Ball Valves Electric Ball Valves Ceramic Core Ball Valves Multiport Ball Valves Rotary Valves Top Entry Ball Valves Floating Ball Valves High Pressure Ball Valves High Temperature Ball Valves V-port Ball Valves

Control Valves



Globe Control Valves

Plug Valves



Cast Iron Plug Valves

Regulating Valves



Cast Iron Regulating Valves

Balance Valves



Cast Iron Butterfly Balance Valve Cast Iron Internal Thread Globe Balance Valve Brass Balance Valve Number-lock Balance Valve

Safety Valves



Closed Spring Loaded Full Bore Type Safety Valve Closed Spring Loaded Low Lift Type Safety Valve High Temperature And High Pressure Safety Valve Pilot Operated Safety Valve Spring Full Bore Type Safety Valve With Radiator Spring Full Bore Type With Lever Safety Valve Spring Loaded Low Lift External Thread Type Safety Valve Spring Loaded Low Lift Type Safety Valve Spring Loaded Low Lift Type With Lever Safety Valve Stainless Steel Spring Loaded Full Bore Type Safety Valve With Handle Twin Spring Type Safety Valve

Instrument Valves



Needle Valves Other Valves

LNG Cryogenic Valves & Accessories



LNG Filling Nozzle Cryogenic Gas Return Nozzle Cryogenic Gas Refueling Receptacle Cryogenic Gas Relief Valve Cryogenic Gas Shut-off Valve Cryogenic Gas Breakaway Coupling Cryogenic Gas Pressure Regulator Cryogenic Gas Check Valve

Pipeline Filters



Cast Iron Filter Cast Steel Filter Stainless Steel Filter Brass Filter

Pipeline & Fittings



Fittings

Flanges



Blind Flange Lap Joint Flange Long Welding Neck Flange Slip-on Flange Socket Welding Flange Threaded Flange Welding Neck Flange Plate Flange Spectacle Blind Orifice Flange Tube Sheet Anchor Flange Swivel Flange Reducing Flange Loose Flange

Customization



Two Way Distributing Valve Rotary Discharge Valve

The Function for Single-port Exhaust Valve and the Double-ports Exhaust Valve

Exhaust valve is a special valve used to prevent negative pressure in the process of stopping the pump water hammer. It is installed in the raised part of the pipeline, inhale air when the pipeline's pressure is below atmospheric pressure; exhaust air when the pipeline's pressure rises above atmospheric pressure. Such valves don't allow fluid to escape into the atmosphere and have the function of closing automatically when removing air from the pipe.

There are single-port exhaust valve and the double-ports exhaust valve two kinds, their function as below:

Single-port exhaust valve is different with double-ports exhaust valve. The single-port one is opened and closed rely on the gravity of the buoy to move the lever up and down; the double-ports exhaust valve make the piston open and close rely on the air discharge and valves ponding.

The Function for Single-port Exhaust Valve and the Double-ports Exhaust Valve

Introduce for single-port exhaust valve:

On the state of exhausting, because of the gravity function, the buoy will pull down one end of the lever, the lever is in the tilt state at this moment and will be a gap in the contact part between lever and the exhaust hole. So the air will be discharged through the gap. As the air discharging, the water level rises, the buoy rises based on water, the lever’s seal face presses the upper of exhaust hole gradually until all exhaust hole are blocked.

The Function for Single-port Exhaust Valve and the Double-ports Exhaust Valve

When the water start to fill in the pipe, plug stays in the open position and exhaust a lot. When the air all exhaust out, valves ponding, float ball is floating, the plug stays in the closed position, stop exhaust air. When the water in the pipe is normally transported, if small amount of air gathered to a certain extent, the water level drops and floating ball drops with it. The air is discharged from the small ball at this time. When the pump stops, the water in the pipe is empty or caused the negative pressure, the plug will be opened quickly and will inhale air to ensure the pipeline is completed.

The Function for Single-port Exhaust Valve and the Double-ports Exhaust Valve