F.A.Q.
VAISHNAVI HYDRAULICS PVT. LTD.  |  INDIA  
Click OK
Search Our Other Websites
    You Are Here : Home / Needle Valves
Check Valves, Non Return Valves
check valves manufacturers, check valve non return valve
Designation & Symbol - CV
  • Check valves are also known as Non Return Valves
  • Check valves are self-activating safety valves that permit gases and liquids to flow in only one direction, preventing process flow from reversing.
  • They are classified as one-way directional valves.
  • Fluid flow in the desired direction opens the valve, while backflow forces the valve closed.
  • The mechanics of check valve operation are relatively simple.
  • Most check valves contain a ball that sits freely above the seat, which has only one through-hole.
  • The ball has a slightly larger diameter than that of the through-hole.
  • When the pressure behind the seat exceeds that above the ball, liquid is allowed to flow through the valve; however, once the pressure above the ball exceeds the pressure below the seat, the ball returns to rest in the seat, forming a seal that prevents backflow.
  • Check valves use a variety of technologies to allow and stop the flow of liquids and gases.
  •  Single-disc swing valves are designed with the closure element attached to the top of the cap.
  • Double-disc or wafer check-valves consist of two half-circle disks hinged together that fold together upon positive flow and retract to a full-circle to close against reverse flow.
  • Lift-check valves feature a guided disc.
  • Spring-loaded devices can be mounted vertically or horizontally.
  • Silent or center guide valves are similar to lift check valves, with a center guide extending from inlet to outlet ports.
  • The valve stopper is spring and bushing actuated to keep the movement "quiet".
  • Ball check valves use a free- floating or spring loaded ball resting in a seat ring as the closure element.
  • Cone check valves use a free-floating or spring loaded cone resting in the seat ring as the closure element.
  • Selecting check valves requires an analysis of performance specifications, materials of construction, connection types, and media.
  • Performance specifications include valve size, pressure rating, media temperature, and valve flow coefficient.
  • Most check valves are made of acetal polymers, aluminum, brass, bronze, cast iron, chlorinated polyvinyl chloride (CPC), ductile iron, copper, polyethylene (PE), polypropylene (PP), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), rubber, steel, or stainless steel.
  • Connections for check valves can use threads, compression fittings, tube fittings, bolt flanges, clamp flanges, butt welds, socket welds, and union connections.
  • In terms of media, check valves are rated for air, compressed air, water, hot water, cold water, potable water, salt water, wastewater, gasoline, diesel fuel, high-purity gas, liquefied petroleum gas (LPG), natural gas, sour gas, corrosive gas, abrasive material, acids, corrosive chemicals, adhesives, concrete, grout, coolants, hazardous materials, high-viscosity fluids, hydraulic fluids, liquid metal, lubricants, oil, powders, solids, rendering wastes, sludge, slurry, ash slurry, or steam.
  • Check valves are available in Steel, Stainless Steel, Brass Materials & can be applicable for Low pressure Application, High pressure Application & for water.


  • Check Valves Series Sizes For Threads Types of Threads Available CLICK to Submit
    Check valves with Female Threads 3000 6000 1/4" up to 2" BSPP/BSPT/NPT/UNF Enquiry Form
    Check valves with Male Threads 3000 6000 1/4" up to 2" BSPP/BSPT/NPT/UNF Enquiry Form
    Check valves with Metric Tube Od 3000 6000 6 mm upto 42 mm od Metric Threads with Nut + Ferrule Enquiry Form
    Check valves with UNF Tube Od 3000 6000 1/4" od up to 2" od UNF Threads with Nut + Ferrule Enquiry Form
    Check valves with Tube to Thread End 3000 6000 6 mm upto 42 mm od Metric to Bspp threads Enquiry Form


    custom check valves, plastic check valves
    Check Valves, Non Return Valves
    Materials
    • Valve Body - Steel Phosphatised / Yellow chromatize / trivalent Zinc Blue Passivation
    • Valve Body - STAINLESS STEEL -304 / 316
    • Valve Spindle - Steel , Stainless Steel 304 / 316
    • SEALING - WITH O RING -NBR - ( Viton - O ring - On Request at Extra Cost only)
    • W.P. = Low Pressure = 200 bar & High Pressure up to 400 bar
    • All other Parts are trivalent Zinc with Blue passivation


    Non Return Valves - Tube to Tube End - For Hydraulic Applications
  • Non Return valves tube to tube end are applicable for the systems where we have use Seamless tubes ( Metric / Inch Od / Inch NB types ) & to connect this tube end to this Non Return valves with Tube end & to Provide Nut & Ferrule Ring to get this tubes Grip with Non Return Valves Body.
  • Non Return vales with Hydraulic tube end utilise in Paper Industry, Steel Plant manufacturer, Power Pack Manufacturer, Aircraft construction equipments, SPM, Process Machineries, Hydraulic Power Booster Units.

  • Non Return Valves with tube to tube end connection are available in below types & sizes:

    Non Return Valves - Tube to Tube End W.P.- BAR Series Sizes for Threads Types of Threads Available CLICK to Submit
    6 MM to 15 MM OD 250 Light 6 MM to 15 MM Metric Threads both end Enquiry Form
    18 MM to 22 MM OD 160 Light 18 MM to 22 MM Metric Threads both end Enquiry Form
    28 MM to 42 MM OD 100 Light 28 MM to 42 MM Metric Threads both end Enquiry Form
    6 MM to 12 MM OD 630 Heavy 6 MM to 12 MM Metric Threads both end Enquiry Form
    14 MM to 25 MM OD 400 Heavy 14 MM to 25 MM Metric Threads both end Enquiry Form
    30 MM to 38 MM OD 250 Heavy 30 MM to 38 MM Metric Threads both end Enquiry Form

    flow check valves, industrial check valves suppliers
    Needle Valve
    Materials
    • Valve Body - Steel Phosphatised / Yellow chromatize / trivalent Zinc Blue Passivation
    • Valve Body - STAINLESS STEEL -304 / 316
    • Valve Spindle - Steel , Stainless Steel 304 / 316
    • SEALING - WITH O RING -NBR - ( Viton - O ring - On Request at Extra Cost only)
    • W.P. = Low Pressure = 200 bar & High Pressure up to 400 bar
    • All other Parts are trivalent Zinc with Blue passivation


    Non Return Valves - Tube to Tube End - For Instrumentation Tube systems
  • Non Return valves tube to tube end are applicable for the systems where we have use Seamless tubes ( Metric / Inch Od / Inch NB types ) & to connect this tube end to this Non Return valves with Tube end & to Provide Nut & Ferrule Ring to get this tubes Grip with Non Return Valves Body.
  • Ball valves with Instrument Tube end utlise for Oil & gas Industry, Marine Application, Petrolium Equipments, Oil Refineries, Water Industry.

  • Ball Valves with tube to tube end connection are available in below types & sizes:

    Non Return Valves with Tube to Tube End W.P.- BAR Series Sizes for Threads Types of Threads Available CLICK to Submit
    1/8" od up to 2" od Tube Size 400 Heavy 1/8" up to 2" UNF Threads both end Enquiry Form
    6 mm up to 50 mm od Tube Size 400 Heavy 6 mm up to 50.8 mm UNF Threads both end Enquiry Form

    check valves manufacturers, plastic check valves
    Non Return Valves - Tube to Tube End - For Instrumentation Tube systems
    Materials
    • Valve Body - Steel Phosphatised / Yellow chromatize / trivalent Zinc Blue Passivation
    • Valve Body - STAINLESS STEEL -304 / 316
    • Valve Spindle - Steel , Stainless Steel 304 / 316
    • SEALING - WITH O RING -NBR - ( Viton - O ring - On Request at Extra Cost only)
    • W.P. = Low Pressure = 200 bar & High Pressure up to 400 bar
    • All other Parts are trivalent Zinc with Blue passivation


    Non Return Valves - Tube to Male End - For Hydraulic Applications
  • Non Return valves tube to tube end are applicable for the systems where we have use Seamless tubes (Metric / Inch Od / Inch NB types) & to connect this tube end to this Non Return valves with Tube end & to Provide Nut & Ferrule Ring to get this tubes Grip with Non Return Valves Body.
  • The other side of the Non Return Valves has Male / Female threads like BSPP / BSPT / NPT as per connection required to the end users.
  • Non Return vales with Hydraulic tube end utilise in Paper Industry, Steel Plant manufacturer, Power Pack Manufacturer, Aircraft construction equipments, SPM, Process Machineries, Hydraulic Power Booster Units.

  • Non Return Valves with tube to Male Thread end connection are available in below types & sizes:
    Non Return Valves - Tube to Male End W.P.- BAR Series Sizes for Threads Types of Threads Available CLICK to Submit
    6 MM to 15 MM OD 250 Light 6 MM to 15 MM Metric X Bsp Threads Enquiry Form
    18 MM to 22 MM OD 160 Light 18 MM to 22 MM Metric X Bsp Threads Enquiry Form
    28 MM to 42 MM OD 100 Light 28 MM to 42 MM Metric X Bsp Threads Enquiry Form
    6 MM to 12 MM OD 630 Heavy 6 MM to 12 MM Metric X Bsp Threads Enquiry Form
    14 MM to 25 MM OD 400 Heavy 14 MM to 25 MM Metric X Bsp Threads Enquiry Form
    30 MM to 38 MM OD 250 Heavy 30 MM to 38 MM Metric X Bsp Threads Enquiry Form

    check valve tube to tube end, flow check valves
    Non Return Valves - Tube to Male End - For Hydraulic Applications
    Materials
    • Valve Body - Steel Phosphatised / Yellow chromatize / trivalent Zinc Blue Passivation
    • Valve Body - STAINLESS STEEL -304 / 316
    • Valve Spindle - Steel , Stainless Steel 304 / 316
    • SEALING - WITH O RING -NBR - ( Viton - O ring - On Request at Extra Cost only)
    • W.P. = Low Pressure = 200 bar & High Pressure up to 400 bar
    • All other Parts are trivalent Zinc with Blue passivation



    All Right Reserved
    CEO 'S DESK ....
    Click OK
    VE-LOCK® Product Warranty
    All VE-LOCK® Brand Make Products Stands for 12 Months Warranty of any defects in material or improper workmanship.The Warranty Stands for Replacements of determined Defective parts only.