What is the difference between a breather valve and a flame arrester?

A breather valve controls the pressure and vacuum inside a storage tank — it opens and closes to allow the tank to breathe safely. A flame arrester prevents flame from travelling through the vent opening. On flammable liquid storage tanks both are needed together. They are available as separate devices or as a combined flame arrester cum breather valve in one fitting.

What sizes of breather valves does Flow Industries manufacture?

Flow Industries manufactures breather valves from half inch to 12 inch (40mm to 300mm). Body material is aluminium alloy for sizes 2 inch, 3 inch and 6 inch, and cast steel for sizes 8 inch, 10 inch and 12 inch. We are based in Ankleshwar GIDC, Gujarat, India.

What is API 2000 for breather valves?

API 2000 is the American Petroleum Institute standard for venting atmospheric and low-pressure storage tanks. It defines the required venting capacity based on tank size, fluid type and filling and emptying rates. Flow Industries breather valves are designed in accordance with API 2000 guidelines.

Can breather valves be used for acid or corrosive chemical storage tanks?

Yes. For corrosive chemical service including acids, alkalis and chlorinated solvents, Flow Industries supplies breather valves with stainless steel SS 316 pallets, seats and internals, and PTFE or Viton seals. Please specify the chemical name, concentration and temperature when requesting a quotation.

What is the difference between a pressure vacuum relief valve and a conservation vent?

They are the same device. A pressure vacuum relief valve (PVRV) and a conservation vent are both names for a breather valve. The term conservation vent emphasises the vapour saving function — by only opening at a set pressure or vacuum it reduces evaporation losses compared to an open vent pipe.

Do you supply breather valves to Ankleshwar and Panoli GIDC chemical plants?

Yes. Flow Industries is located at Plot No. 115, Yogi Industrial Estate, GIDC, Ankleshwar, Gujarat and regularly supplies breather valves to chemical and pharmaceutical plants in Ankleshwar GIDC, Panoli GIDC, Jhagadia GIDC and Dahej SEZ. Call us at +91 98244 66603.

Can a breather valve and flame arrester be supplied as one combined unit?

Yes. Flow Industries manufactures a flame arrester cum breather valve — a single fitting combining both functions. This is the most popular choice for flammable liquid storage tanks as it reduces the number of tank nozzles used and simplifies installation and maintenance.

Breather Valve Manufacturer in Ankleshwar, Gujarat — Pressure & Vacuum Relief Valves for Storage Tanks

Name: Breather Valve
Brand: Flow Industries
Availability: InStock

Flow Industries is a leading breather valve manufacturer based in Ankleshwar, GIDC, Gujarat, India. We manufacture pressure and vacuum relief valves — also known as conservation vents or tank breather valves — designed to protect fixed roof storage tanks and process vessels from over-pressure and vacuum conditions caused by product movement, temperature changes and tank filling and emptying operations.

Our breather valves combine pressure relief and vacuum relief functions in a single fitting. Available in sizes ½" to 12" (40mm to 300mm), manufactured in aluminium alloy body for sizes 2", 3" and 6", and cast steel body for sizes 8", 10" and 12". Widely used in chemical, petrochemical, pharmaceutical, oil & gas, distillery and storage terminal industries across India.

ISO 9001:2015 certified. Over 20 years of manufacturing experience. Trusted by Sun Pharma, Pidilite, Hindalco, GFL, Navin Fluorine, Alembic and 100+ leading industries across Gujarat and India.

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Pressure Relief

Vacuum Relief

Conservation Vent

½" to 12" Sizes

Aluminium Alloy Body

Cast Steel Body

Flanged Ends

Tank Breathing Protection

Vapour Conservation

Types of Breather Valves We Manufacture

Standard Pressure Vacuum Relief Valve (PVRV)

The standard breather valve combines pressure and vacuum relief in a single body. It is the most widely used tank safety device for fixed roof storage tanks handling flammable liquids, chemicals and petroleum products. The pressure pallet opens when tank pressure exceeds the set point and the vacuum pallet opens when vacuum exceeds the set point — both functions in one compact fitting.

pressure vaccum relief manufacturer Ankleshwar Gujarat India Flow Industries

Parameter	Details
Applications	Fixed roof storage tanks — petroleum, chemical, pharma
Standards	API 2000, EN ISO 28300
Operating Temp	-20°C to +150°C
End Connection	Flanged ANSI 150# / BS / DIN; Screwed BSP/NPT

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Key Features:

Combined pressure and vacuum protection in one fitting
Adjustable pressure and vacuum set points
Aluminium alloy body — lightweight for tank-top installation
PTFE / Viton seals for chemical resistance
Weatherproof design for outdoor installation
Low fugitive emissions — reduces vapour loss significantly
Available with stainless steel internals for corrosive service

Applications:

Petroleum product storage tanks — diesel, petrol, crude
Chemical storage tanks — solvents, acids (with SS internals)
Pharmaceutical solvent storage vessels
Edible oil and food grade storage tanks
Distillery and alcohol storage tanks

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Flame Arrester Cum Breather Valve

The flame arrester cum breather valve combines both functions — pressure vacuum relief and flame arrest — in a single compact unit for tank top installation. This eliminates the need for separate flame arrester and breather valve fittings, reducing installation cost and nozzle usage on the tank roof.

This combined unit is the most common tank safety fitting for flammable liquid storage tanks in chemical, petrochemical and petroleum industries — providing complete tank breathing protection and ignition prevention in one device.

arrester cum breather manufacturer Ankleshwar Gujarat India Flow Industries

Parameter	Details
Applications	Flammable liquid storage tanks — chemical, petroleum, distillery
Standards	API 2000, EN 12874, EN ISO 28300
End Connection	Flanged ANSI 150# / BS / DIN
Vacuum Setting	Adjustable as per tank design

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Key Features:

Single unit replaces separate flame arrester + breather valve
Saves one tank nozzle — lower installed cost
Stainless steel flame element — corrosion and fouling resistant
Pressure and vacuum pallets independently adjustable
All-weather design — UV resistant seals
Suitable for Group IIA and IIB flammable vapour service

Applications:

Flammable solvent and chemical storage tanks
Petroleum storage tanks — crude, diesel, petrol, naphtha
Alcohol and ethanol storage tanks in distilleries
Hazardous liquid storage in pharmaceutical plants
Tank farm storage terminals

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Vacuum Breather Valve

A vacuum breather valve — also called an emergency vent or vacuum relief valve — provides vacuum protection only, without a pressure relief function. It is used on tanks where the primary risk is vacuum collapse rather than over-pressure, or where a separate high-capacity pressure relief vent is already installed.

vaccum breather valve manufacturer Ankleshwar Gujarat India Flow Industries

Parameter	Details
Applications	Tanks with separate pressure relief — vacuum protection only
Standards	API 2000
Operating Temp	-20°C to +120°C
End Connection	Flanged ANSI 150# / BS / DIN; Screwed

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Key Features:

Vacuum protection only — no pressure pallet
High flow capacity for rapid tank emptying protection
Suitable for large volume storage tanks
Lightweight aluminium body for tank-top mounting
Stainless steel internals available for corrosive service

Applications:

Water and non-flammable liquid storage tanks
Tanks with separate emergency pressure vents
Large storage tanks requiring high vacuum flow capacity
Underground tanks with vacuum collapse risk

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Breather Valve Selection Guide

Use this guide to select the right breather valve for your storage tank application.

Tank Fluid	Flame Risk	Recommended Device
Pharmaceutical solvents	High	Flame arrester cum breather valve
Alcohol / distillery	High	Flame arrester cum breather valve
Corrosive chemicals (HCl, H₂SO₄)	Check	PVRV with SS 316 / PTFE internals
Edible oil, food grade	None	Standard PVRV — SS internals

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Pressure and vacuum setting guide:

Tank Type	Typical Pressure Setting	Typical Vacuum Setting
Higher pressure vessel	Customer specified	Customer specified
Low pressure storage tank	+2 oz/sq.in to +8 oz/sq.in	-1 oz/sq.in to -4 oz/sq.in
Atmospheric cone roof tank	+0.5 oz/sq.in to +2 oz/sq.in	-0.5 oz/sq.in to -1 oz/sq.in

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Note: Always verify pressure and vacuum settings with your tank design engineer before ordering. Settings must not exceed the tank shell design pressure.

Where Our Flame Arrester Are Used

Chemical & Petrochemical

Solvent storage tanks, acid and alkali storage vessels (SS internals), chemical feed tanks, intermediate chemical storage, process vessel conservation vents.

Pharmaceutical

Solvent storage and day tanks, solvent recovery vessel vents, pharmaceutical intermediate storage, API storage tanks in bulk drug manufacturing.

Oil & Gas

Crude oil tanks, diesel and petrol storage tanks, naphtha tanks, lube oil storage vessels, fuel oil tanks at power plants, loading and unloading terminal storage tanks.

Water & Wastewater Treatment

Non-flammable liquid storage tanks, chemical dosing tank vents, water storage tank vacuum protection.

Paint & Coatings

Solvent tank conservation vents, thinner storage tanks, raw material storage in paint manufacturing plants.

Distilleries

Ethanol and spirit storage tanks, molasses storage vessels, fermented wash holding tanks, alcohol blending tank vents.

Why Choose Flow Industries Flame Arresters?

ISO 9001:2015 Certified Manufacturing

Every breather valve manufactured under a certified quality management system with complete documentation, material traceability and functional testing before dispatch.

Combined Pressure & Vacuum in One Fitting

Our standard breather valve handles both pressure relief and vacuum relief in a single body — reducing tank nozzle usage, installation complexity and maintenance points.

Complete Range — Single Unit to Combined Type

Standard PVRV, flame arrester cum breather valve and vacuum-only types — all manufactured in-house at our Ankleshwar GIDC plant. Custom pressure and vacuum settings available.

Chemical Resistant Materials

PTFE, Viton and Neoprene seal options. SS 304 and SS 316 internals for corrosive chemical service. Suitable for acids, solvents, alkalis and aggressive petroleum fractions.

Trusted by Major Gujarat Industries

GFL, Navin Fluorine, Alembic Pharma, Jubilant Life Sciences, Pidilite — Gujarat chemical and pharmaceutical industry leaders trust Flow Industries for tank safety equipment supply.

Local Manufacturer — Fast Delivery

Based in Ankleshwar GIDC — close to the major chemical belt of Bharuch, Panoli, Jhagadia and Dahej. Fast delivery, local support and on-site availability for urgent requirements.

FAQs

Breather Valve

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A breather valve controls the pressure and vacuum inside a storage tank — it opens and closes to allow the tank to breathe safely. A flame arrester prevents flame from travelling through the vent. On flammable liquid storage tanks, both are needed together — the breather valve controls when the vent opens and the flame arrester prevents ignition. They are available as separate devices or as a combined single unit.
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Your Application

Looking for a breather valve or conservation vent for your storage tank? Share your requirements and we will recommend the right type, size and pressure setting with a competitive quotation.

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✓ ISO 9001:2015 Certified

📞+91 98244 66603

📞+91 98245 66603

✉️info@flowindustriesindia.com

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