How to choose a membrane tank
Constantly changing temperature and pressure in the plumbing system can create problems for the apparatuses, for the functioning of which stability is necessary. Uninterrupted water supply may also be affected.
Membrane tanks are used to minimize the effect of fluid pressure on devices.
These designs are different not only in size, but also in operational properties, so before choosing a membrane tank you need to know all its varieties and functions. How to choose a membrane tank and not make a mistake, we will tell in this article.
Principle of action
With the help of the diaphragm all tanks are divided in half. In the first part of the product is the air compressed by a certain pressure. In the second half, coolant will flow after expansion under the action of temperature. The airbag creates high pressure when liquid enters the product.
When the coolant is cooled, returning to itself the initial volume, from the membrane tank, under the pressure of the air cushion, the excess is returned. Thus, the level of the coolant always remains stable, do not let the system fail.
Varieties
For the manufacture of membrane tanks using conventional and stainless steel. Volumes of these products range from 25 liters to 50. Membranes can be replaceable or non-replaceable. You can calculate the required volume, knowing the length of the water mains.
Replaceable membranes
Replaceable membranes используются во фланцевых баках.
Membrane tanks are vertical or horizontal.
It is interesting that the coolant, falling into such a product, is located in the central part, not in contact with the walls. Since the contact of the liquid with the inside of the product does not occur, there is no need for anti-corrosion coating. The membrane of the same technology can be changed through the flange, which is mounted on just a few fasteners.
Fixed membranes in tanks
Fixed such a membrane around the perimeter. The inner side of the wall is treated with epoxy paint to prevent corrosive processes. When the membrane is in the initial position, it is pressed very tightly against the walls by the air inside it. The obvious lack of a product is the impossibility of changing the membrane, but with careful treatment it will last a long time.
Open or closed?
Not so long ago, open tanks provided the heating system to the full, but they had many flaws.
- Since the system is open, air could enter it, which could interfere with circulation.
- Loud sounds in the pumps and piping accompanied the work of such products.
- The coolant could evaporate.
- An open system needed to be installed only in the upper points, which helped to get rid of interruptions in its work.
In the closed products of the similar plan these defects are eliminated. Largely due to the fact that the coolant is not in contact with the environment.
Let's see what needs to be considered when calculating and how to choose a membrane tank, based on our knowledge.
Membrane
The membrane is the main element on which the efficiency of the product depends, and its choice is based on the purpose of the system. Tanks that provide high-quality work of heating and water supply are similar in appearance, therefore some sellers confuse them, offering not what they need.
The main criterion when choosing a membrane - resistance to temperature and duration of operation. In the heating system of private houses, the heating of the working fluid is slow, which means that a large load on the tank is not expected. Sometimes the temperature of the liquid can reach 90 degrees, so you need to choose a product with high wear resistance. It is also important elasticity of the material.
Operating parameters
You will receive information on the selected tank from the indicators of operating temperature and permissible pressure. According to the manufacturers, modern closed-end products withstand up to 110 degrees, while the pressure - 8-10 bar.
When the coolant is heated by 10 degrees, its volume increases by 0.3%. That is, when the fluid is heated to 70 degrees, its volume will increase to 103%. The working volume you need can be calculated using the formula that each vendor should have.
Membrane tanks allow you to get rid of problems in the future. The use of such products reduces the number of breakdowns and helps avoid frequent repairs. Choosing a quality tank, you will get rid of the shortcomings of the heating and water supply system.
Video
The video tells how to choose a membrane tank (hydroaccumulator).