An air vent might seem like a simple component, but in reality, it protects the entire tank structure.
Without it, even the strongest stainless steel tank could face structural strain or worse, or collapse due to pressure imbalance.
This report explains why air vents are crucial and what can happen if they are not taken care of properly.
In this blog, we’ll break down what an air vent actually is, and why stainless steel tanks need them. We will also look at the functions they perform, the different types available, and the best solution.
By the end, you’ll see why such a small part deserves big attention. Let’s dive in!
An air vent is a controlled opening that allows air to move in and out of a water tank during operation. You can also think of it as a pressure equaliser.
Here’s how it works.
When water pours into a tank, the air inside needs to have some room to escape; otherwise, the pressure starts building up. You can imagine it getting to a point where the tank is going to burst.
The same thing happens the other way round, when water is being pulled out of the water tank. The air needs to come inside to fill up the space that's been emptied. If it can't, then you get a vacuum forming inside.
Try to picture this: trying to take a sip from a bottle that hasn't been opened properly, the water will come out unevenly with a glugging sound. This will happen because the air can't get into the bottle to fill the space.
The same thing is happening in a water tank, without an air vent to let air in and out. The tank can't balance the pressure inside and outside, which puts loads of stress on the panels and joints.
It can get so bad that the pressure difference starts to warp the tank walls, or even worse, makes them collapse over time.
Having an air vent / multiple air vent valves, though, solves this problem. It allows the air to just swirl in and out as needed, keeps the pressure in balance, the structure safe, and the tank working just fine.
Now, you might wonder, stainless steel tanks are incredibly durable, so why bother about something as simple as an air vent?
The truth is, strength alone isn’t enough when pressure forces are at play.
Let’s consider a few scenarios.
In stainless steel water tanks, which are often modular and built with precision-fit panels, these pressure changes can cause noticeable distortions. Over time, that can compromise both aesthetics and function.
When tanks are properly vented, they perform quietly, efficiently, and safely. When they’re not, problems often go unnoticed until it’s too late.
Air vents do more than just let air move. They perform several small but critical jobs that keep the tank balanced and long-lasting.
When water fills the tank, the trapped air must escape. The air vent releases this air gradually to prevent a build-up of pressure that could push against the tank walls.
When the tank empties, the space left behind must be filled with air to balance the pressure. The vent allows outside air to flow in, preventing the vacuum that can crush panels inward.
Tanks “breathe” - not in the literal sense, but through air exchange as water levels change. This constant movement of air ensures the system operates smoothly without sudden pressure changes.
Without pressure balance, seams, bolts, and welds take unnecessary stress. Over time, this can cause leaks or warping. The vent prevents that by equalising pressure on both sides.
A well-designed air vent keeps dust, insects, and debris out while allowing air movement. It helps maintain clean storage conditions and supports water hygiene.
Many people panic when they see water spilling slightly from the vent during tank filling. In fact, that’s perfectly normal. It means the vent is doing its job, releasing internal pressure as the tank reaches capacity.
Types of Air Vents Used in Water Tanks
There’s no single type of air vent that fits every tank. The right one depends on size, use, and environmental factors.
ABS (Acrylonitrile Butadiene Styrene) vents are a popular choice for stainless steel tanks because the material is strong, lightweight, and corrosion-resistant. Beltecno, for example, uses imported ABS air vents for durability and consistent quality.
Beltecno uses two main vent sizes based on tank capacity:
This sizing ensures the right airflow for each tank volume, preventing under- or over-ventilation.
3. Passive and Active Vents
Passive vents rely on open pathways covered by mesh to let air move freely. Active vents include valves that open and close under specific pressure conditions, are ideal for systems where pressure variations are significant.
Besides ABS, some manufacturers use stainless steel, aluminium, or polycarbonate depending on the tank environment. For stainless steel tanks, corrosion resistance and durability are top priorities.
The vent is usually positioned at the topmost point of the tank, where air naturally collects. Proper placement ensures efficient air movement and prevents stagnant zones.
Even a perfectly designed vent can underperform if it’s not installed correctly. That’s why good manufacturers, like Beltecno, ensure the vent’s location, size, and fitting are integrated into the tank design from the start.
Read about: Beltecno’s Lightweight yet Strong and Durable Stainless Steel Water Tanks
Here’s a quick comparison table to highlight the difference:
|
Feature |
Generic Air Vent |
Beltecno Air Vent |
|
Material |
Basic plastic or mild steel |
Imported ABS (Acrylonitrile Butadiene Styrene) |
|
Origin |
Local or generic |
Imported from Japan |
|
Sizes |
One-size-fits-all |
NB 100 for big tanks, NB 50 for smaller ones |
|
Durability |
Prone to cracking or corrosion |
Long-lasting and weather-resistant |
|
Design precision |
Standard |
Custom-engineered for Beltecno modular tanks |
|
Hygiene control |
Basic mesh |
Enhanced air balance and hygiene-focused design |
|
Integration |
Added after fabrication |
Built as part of the tank system |
This attention to detail shows why Beltecno’s tanks are trusted for safety, performance, and hygiene.
Even a small part like the air vent/ air vent valves reflects the same philosophy that drives their entire manufacturing process, quality through precision.
Read About: Stainless Steel Tank Benefits
Q1) What is the difference between Air Vent and Air Vent Valves?
An air vent is a simple opening that lets air move in and out of a tank to balance the air pressure. On the other hand, an air vent valve is a mechanical device that automatically
opens or closes to release trapped air or admit air when needed, commonly used in pressurised systems.
Q2) What is the purpose of air vents in tanks?
Air vents in tanks are essential because they let air in and out as the water level changes. This stops the pressure from building up or creating a vacuum, the sort of thing that can cause all sorts of damage to your tank. They also help the water flow smoothly & keep the tank running quietly & safely.
Q3) What's the difference between a vented and an unvented water tank?
A vented water tank is basically one that lets air move in and out through an opening in the side; it keeps the pressure in check in there. An unvented tank is sealed up tight & uses valves to control the pressure inside. Unsurprisingly, vented tanks are a fair bit simpler and safer to store, while unvented ones are a bit trickier to manage & are usually used in systems that need a bit of pressure.
It’s easy to overlook an air vent when looking at a massive stainless steel water tank. But that small component is doing some heavy lifting behind the scenes.
So the next time you’re evaluating a stainless steel tank, ask one simple question: What kind of air vent does it use? The answer will tell you a lot about the quality and reliability of the system.
To order or to enquire about your perfect stainless steel water tank, Contact Us!
Stainless steel, an alloy known for its corrosion resistance, is the material of choice for stability are invaluable. Welded steel storage tanks can safely store both hot and cold energy. They offer a dependable option for industries that want a sustainable way to manage their energy use.
TES tanks store hot or cold energy during off-peak hours, optimizing energy usage and reducing costs.
Unlike pre-fabricated tanks, welded steel storage tanks are highly customizable. They can be designed to fit specific capacity, shape, and dimensional requirements, making them suitable for unique operational needs.
Welded steel storage tanks can be designed to handle high pressure and tough environmental conditions. They can meet the strict demands of many industrial processes. This flexibility is particularly useful for industries like manufacturing, where space constraints and custom storage needs are common.
TES systems store energy as heat or cold for later use. When energy demand is low, they use the extra energy to create heat or cold and then store it in tanks filled with water or a phase change material.
When energy demand peaks, the stored thermal energy is released, reducing the load on traditional power sources. This load management is especially beneficial for energy-intensive industries, where energy costs fluctuate widely.
TIG welding is very effective for making welded steel storage tanks used in thermal energy storage systems. It offers high precision and strong welds, which are important for tanks that must handle heat and pressure.
This method uses a tungsten electrode and an inert gas like argon or helium to protect the weld from contamination. The welds are clean, smooth and durable, with very few defects.
TIG welding reduces problems like porosity and small gaps that can cause heat loss or leaks. This is important for TES systems because even small flaws can affect temperature control and reduce energy efficiency.
The smooth and corrosion resistant weld seams also help the tank handle repeated heating and cooling cycles. This improves the long term performance of tanks that store both hot and cold energy.
Because TIG welding creates strong and precise joints, the entire tank stays stable under high temperatures and pressure. The method also works well with stainless steel, which has low thermal conductivity. This reduces the need for extra insulation.
Overall, TIG welding and stainless steel make welded tanks highly efficient for TES. They help preserve stored energy, maintain steady temperatures and support clean, energy saving industrial operations.
India’s industrial sector is growing fast, and that growth puts real pressure on the country’s energy and water resources. As India moves toward its sustainability goals, the need for smarter, more efficient infrastructure becomes hard to ignore.
Welded steel storage tanks, especially those designed for thermal energy storage, fit neatly into this shift. They support cleaner energy use, reduce waste and help industries cut their overall environmental footprint.
Welded steel storage tanks are also widely used for storing water, a critical resource in industrial and commercial settings. Their corrosion-resistant properties make them ideal for ensuring clean, uncontaminated water storage. Additionally, by incorporating TES systems, industries can reduce their dependence on non-renewable energy sources and contribute to a more balanced energy grid.
Industries in India are subject to stringent environmental regulations, making compliance a significant factor in storage solutions.
Welded steel storage tanks meet high safety and hygiene standards, making them compliant with regulations in sectors like pharmaceuticals, food processing, and manufacturing. Stainless steel tanks offer the benefit of easy maintenance and frequent sanitization.
The upfront cost of welded steel storage tanks can be higher than other options, but they tend to pay for themselves over time. Their long service life and low maintenance needs cut down on unexpected repairs and replacement expenses.
Industries also see fewer disruptions, which keeps operations running smoothly. For companies that value sustainability and steady performance, welded steel storage tanks are a practical and financially smart choice.
Choosing welded steel storage tanks for TES and other industrial uses reflects a clear move toward cleaner and more efficient infrastructure.
These tanks make it easier to store thermal energy, which helps industries tap into renewable sources more effectively and support global sustainability efforts.
Sectors like power, manufacturing, and food processing gain a lot from this approach. When companies invest in welded steel storage tanks, they strengthen their operations while cutting down their overall energy use. It’s a practical step that supports India’s broader focus on sustainable growth.
Read more about the use of thermal storage tanks in data centers to go green & efficient.
Welded steel storage tanks offer unmatched durability, corrosion resistance, and thermal efficiency, making them the ideal choice for industries that require reliable storage solutions. Their application in thermal energy storage further enhances their value, enabling businesses to manage energy more effectively and support sustainable practices.
As India’s industrial landscape expands, welded steel storage tanks are becoming essential for meeting rising energy and water storage needs. Their long-lasting, sustainable performance makes them a vital part of modern infrastructure.
By choosing Beltecno welded steel storage tanks, industries can ensure they’re investing in quality, sustainability, and the future of energy management.
If you want to learn more about how we can assist you in getting your perfect SS tank please Contact Us.