In this new article, we list the stainless steel accessories and safety valves used in tank setups, focusing on their functionality and utility. For better understanding, we can carefully observe the image above which shows a fully equipped stainless steel tank and provides
a complete list of generally used stainless steel accessories and valves, along with their positioning in the storage tank.
STAINLESS STEEL MANWAY DOORS AND STAINLESS STEEL MANHOLES
Stainless steel manway doors and stainless steel manholes are critical installation’ components in many industrial sectors, particularly those managing liquids or chemicals, as well as the food and pharmaceutical sectors.
Stainless steel manways are located on the lateral-bottom sides of tanks and containers; they are used for their inspection, washing and partial or complete emptying.
Stainless steel manholes are installed on the top of storage tanks and, as stainless steel manways, are available in various models with different features.
Some stainless steel manholes’ models have vent holes or anti-retention covers; the upper manhole with glass allows the inspection of the product processing inside the tank.
Stainless steel manways and stainless steel manholes must ensure an hermetic closure in order to prevent contamination and product loss; their structure must withstand the pressure exerted by the product stored in the stainless steel tank, and the material they are made of must be suitable for the technical needs of the application (e.g., AISI 304 or AISI 316 stainless steel).
To further explore the topic, we recommend reading our article: “Stainless Steel Manways and Manholes: Buying Guide.”
SAFETY VALVES
Here below, we describe the functioning of the main safety valves used in tanks, that are the discharge valve, vacuum valve spring loaded, double-action reflief valve, and bunging devide.
DISCHARGE VALVES
The discharge valves are installed at the top of stainless steel tanks.
They are used to stabilize internal pressure in case of overpressure situations according to the production process specifications, thus preventing damage to the tank and its accessories.
They can be categorized into free discharge valves and angle-body regulating valve.
Free discharge valves activate in overpressure scenarios, allowing gas to flow out and reduce internal pressure and temperature of the stainless steel tank. Angle-body regulating valve operates on the same principle of free discharge valves, but they direct fluids into a dedicated recovery conduit.
Both types of discharge valves are available as adjustable version – spring relief valve (where the user can set the opening pressure) and standard non-adjustable versions.
VACUUM VALVE SPRING LOADED
A vacuum valve spring loaded, protects tanks, cisterns, and installation’ systems from negative pressure (lower than atmospheric pressure). The vacuum valve spring loaded operates by constantly monitoring the differential between atmospheric pressure and internal tank pressure.
If this value falls below the operational differential of the vacuum valve spring loaded, or the user-set differential in adjustable vacuum valves, the valve will open and generate an air suction into the tank.
The vacuum valve spring loaded is fundamental in order to prevent damage from vacuum conditions, such as tank deformation or contraction (implosion).
DOUBLE-ACTION RELIEF VALVE
The double-action relief valve balances the internal tank pressure, preventing it from falling below atmospheric pressure (depression) or rising above a certain limit (overpressure), thus protecting the tank and its accessories from potential damage.
These safety valves are available in adjustable (for overpressure only) and standard non-adjustable versions too.
BUNGING DEVICE
A bunging device is a gas safety valve that opens when the internal tank pressure exceeds the user-set value. When activated, the gas in the tank escapes into a glass cup that surrounds the valve, restoring the proper pressure level inside the tank. For correct operation, the glass cup must contain water.
The bunging device also prevents oxygen from entering the tank, allowing for anaerobic fermentation, that is created without air.
As it is quipped with a pressure gauge, the bunging device allows continuous monitoring of the tank’s internal pressure.
Bunging devices are frequently used in tanks and fermenters for the producton of beer, sparkling wine, and any beverage or liquid that generates fermentation/gas.
OTHER ACCESSORIES FOR SETUP CIP-TOP TANK SAFETY VALVE
The cip-top tank safety valve is a combination of safety devices for overpressure, vacuum, CO2 discharge recovery and tank cleaning. This accessory is installed at the top of the tank; overpressure and vacuum values can be user-adjusted according to system needs.
Tank cleaning is done via a washing ball (which can be a rotating washing ball) installed at the CIP-TOP rod base, that will be inserted into the stainless steel tank or cistern.
STAINLESS STEEL ROUND MANHOLE WITH FULL SIGHT GLASS AND PERIPHERAL CLOSINGS
The stainless steel round manhole with full sight glass and peripheral closings is installed at the top of the tank. Thanks to the vision through the glass, this accessory allows you to inspect the working process of the product that take place inside the tank. It is used in particular to observate the fermentation process.
SAMPLING COCKS AND LEVEL COCKS
The sampling cock is a rod (made of glass or plexiglass) installed on the side wall of the stainless steel tank. It’s connected at its upper end to an upper level porter tap, and at its lower end it is connected to a lower level porter tap.
The level cock measures the liquid level inside the stainless steel tank or stainless steel cistern.
In order to permit the collection of the fluid from the stainless steel tank or the stainless steel cistern, the lower level porter tap, connected to the rod at its upper part and featuring a drain hole at the lower part, can be opened to draw a product sample.
SAMPLING COCK
A sampling cock is a stainless steel faucet installed on the tank or cistern’s side wall. This stainless steel accessory allows for sample collection of the liquid inside the stainless steel cistern in order to monitor the processing stages.
There are various types of sampling cock, for example those with hose fittings, sampling cocks with curved fittings, sampling cocks with GAS threaded connections, and sampling cocks with DIN connections.
In the Accessories section of our catalogue are listed the most used sampling cocks for tank setups.
BUTTERFLY VALVE
The butterfly valve is one of the most commonly used types of valves for regulating fluid flow.
It is called “butterfly” because its operation is based on a closing disc mounted on a central stem, and this shape resembles of a butterfly with open or closed wings. The opening and closing of the valve is achieved by rotating the stem on which the butterfly is mounted. The valve is open when the butterfly is positioned diagonally or perpendicularly to the diameter of the tube, thus allowing the fluid to flow, and is closed when the butterfly is positioned parallel to the diameter of the tube, because the butterfly closes the passage and stops the flow of fluid.
BALL VALVE
Ball valves are used in many types of installations, such as food, chemical and hydraulic plants, to manage the flow of liquid and semi-liquid products, allowing them to be closed, opened and reduced.
It is equipped with a spherical shutter with a central cylindrical hole, commonly called “ball”, and depending on the position of the central hole in relation to the axis of the valve, the closing, opening or partitioning of the fluid flow is achieved.
The valve is open and allows fluid to pass when the central hole of the ball is positioned in line with the valve axis, while the valve is closed and stops the flow of fluid when the central hole of the ball is positioned perpendicular to the axis of the valve.
SIGHT GLASS
The sight glass is a stainless steel accessory that allows you to create a transparent window (glass) through which you can visually inspect the flow of fluids inside an equipment, or to safely and reliably monitor the production process within a tank, or a tank.
For more information about stainless steel manways, stainless steel manholes, stainless steel accessories and sight glasses, you can view our products’ catalogue or you can contact us by phone on +39 0421-679996 or by mail at export@venetaacciai.it