How to determine silumin. How to tell a good mixer from a bad one

Engineering systems 12.06.2019

Engineering systems

4821

11/10/2017 Irina RYABOVA.

Instead of a brass faucet, a man was sold a silumin faucet at the market. Can a simple layman distinguish one from the other and how not to “get into a mess”, the WB journalist found out.

Evgeniy I bought a mixer on the "bird". The seller assured him that it was brass. But the mixer quickly broke down. Then Eugene realized that he had been deceived.

“Probably it was made of powdered silumin. There was no time to deal with all this, and I “released everything,” Evgeny told WB.

After some time, the mixer was required by relatives. This time, Eugene approached the issue of buying a device scrupulously: he read on the Internet how to distinguish one from the other.

- It turned out that they are marked differently: on silumin, after letters and numbers, there is also the letter “B”. Armed with knowledge, I come to the market and ask the seller: “Is it really brass?” He says yes. I look at the label. It looks like the person is lying.

Then Eugene asked to see the product catalog, but received a response from the seller: "if you don't like it, don't take it." Another story repeated itself. Only the third showed the desired markings. According to Eugene, many people face similar problems.

"VB" asked the sales assistant of one of the stores Alexandra selling plumbing, how to avoid fraud when buying a faucet.

Today, mixers are sold from two materials: silumin (an alloy of aluminum and silicon) and brass (an alloy of copper and zinc). The former are of lower quality, as they are more fragile. We issue a 5-year warranty for brass mixers, and a year for silumin mixers. Usually silumin mixers weigh less and are cheaper. But this is optional. Some manufacturers mix more than heavy metals to increase the weight. So in appearance and weight it is not always possible to distinguish cheap material from real brass;
The marking itself will also not help to recognize brass and silumin faucets. Not always in a product from silumin there will be a letter "B". Marking will help only in one case: if the seller has a product catalog in which it is easy to find the product by number and read about it detailed information. Knowing the article, you can find information on the Internet;
Tip one: buy goods in trusted places, from reliable sellers. In this case, they will show you the catalog, and they will issue a guarantee, and a check.

plumber Vladimir, who, on duty, deals with various mixers, told us the following:

- On the market, silumin faucets are often slipped to people instead of brass ones. To the common man it is impossible to figure it out, even a specialist will not always notice the difference. Although usually brass is heavier. Recently, I changed a mixer for a woman, which had stood for 30 years. I unscrewed it, I was afraid that the eccentrics would break, because it had “boiled” for so many years. This power is felt, even with a glance. And there is only one advice: buy a mixer in a reliable store.

The situation was commented Chief Specialist, Commissioner for Consumer Rights Protection of the Department of Trade and Services of the City Executive Committee Natalya Petukhova:

– It should be noted that the consumer very correctly and competently approached the purchase plumbing equipment, having previously studied the information about the product that you decided to purchase, taking into account your preferences and wishes.

To say that sellers, by selling silumin mixers, deceive buyers, according to Natalya Petukhova, is wrong. If the product has been certified, has documents confirming its quality, then it cannot be said that it is of poor quality and cannot be sold.

- But it is unacceptable for the seller to mislead the consumer by providing incomplete or inaccurate information about the product. Fortunately, this practice is not a system. In the Department of Trade and Services, applications from citizens with a claim on the quality of sanitary equipment for Last year not received.

What does the law say?

the consumer has the right to free choice of goods of good quality at a convenient time for him, taking into account the seller's working hours;
The seller is obliged to provide the consumer with the necessary and reliable information about the offered goods in a timely manner;
The consumer has the right to return the goods of proper quality within 14 days from the date of transfer of the non-food product to him. The demand of the consumer to return the goods is subject to satisfaction if the goods were not in use, its consumer properties are preserved and there is evidence of its purchase from this seller.

When buying a colored faucet, it is very difficult to determine by the shade of the surface what material it is made of. However, this difficulty is also present for buyers of chrome-plated, nickel-plated and other plumbing models, the color coating simply more reliably hides the source material. By weight, it is also not always possible to distinguish the base material of the mixer, since individual manufacturers have learned to make stampings from alloys specially weighted with lead and other similar metals.

How to determine the quality of a color mixer and find out what it is made of?

First of all, you should pay attention to the accuracy and correctness of the shape of the parts. Brass products are made exclusively by casting, and most often by centrifugal casting. Due to this method of production, the quantity possible defects castings (shells, cracks, surface irregularities) tends to a minimum, respectively, the quality of the mixer is very high. Even if a part of two halves is used for the mixer body, they must be machined, and it is impossible to find the joint under the coating. Cheap silumin mixers are made by stamping without subsequent machining, and the junction line of the stamps is perfectly visible even under the coating.

When choosing, you can also focus on the wall thickness (if the design of the model allows you to determine this). Cast blanks cannot be very thin-walled, this is contrary to the principles of the production method. Stamped parts, on the contrary, are made with a minimum wall thickness to save material.

The inside of the faucet is usually not galvanized and has the natural color of the original material. Therefore, the golden hue of brass on the inner surfaces will help the user determine the quality of the product, but there may be nuances here too - for example, the silumin alloy is given a color close to the color of brass with the help of additives.

So, when choosing a color mixer, you should pay attention to such details:

material color on internal surfaces;
product weight;
Wall thickness;
the presence is clearly visible joints half parts.

If the product seems heavy, has a characteristic golden hue inside, the walls are smooth or with traces of machining and have a thickness of at least 1 mm, then you have a high-quality brass model in your hands.
If in doubt, it is better to compare several models from different price categories and ask the manager - savings in this matter can cause significant costs later, when a fragile silumin mixer causes a “flood” in the apartment.

How to determine the quality of a color mixer and find out what it is made of?

First of all, you should pay attention to the accuracy and correctness of the shape of the parts. Brass products are made exclusively by casting, and most often by centrifugal casting. Due to this method of production, the number of possible casting defects (shells, cracks, surface irregularities) tends to a minimum, respectively, the quality of the mixer is very high. Even if a part of two halves is used for the mixer body, they must be machined, and it is impossible to find the joint under the coating. Cheap silumin mixers are made by stamping without subsequent machining, and the junction line of the stamps is perfectly visible even under the coating.

So, when choosing a color mixer, you should pay attention to such details:

material color on internal surfaces;
product weight;
Wall thickness;
the presence of clearly visible joints of the halves of the parts.

Hello.
An eccentric with a facing washer was used to supply a stainless heated towel rail to the pipe; in just 4 years of operation, the eccentric rotted and burst. It is clear from the chip that the eccentric is not brass, but silumin. If in doubt, rub the “nickel-plated” part of the part with a nail file or needle file, scratch it with a nail, and if the scratches shine yellow, then this is brass, if the scratch is white or gray, then this is silumin. Also, silumin faucets or parts are unusually light. Silumin is a strong, but fragile material, highly porous, the use in plumbing ALWAYS ends badly, without exception.

An accident occurred in a private house: at first, the heating system began to lose water and the owner was surprised that he had to wait for a leak somewhere, then the door swelled and the culprit was discovered. It is very interesting that the eccentric is completely overgrown with scale from the inside in just a few years of operation, this does not happen with brass fittings. When trying to unscrew the remnants of the part, the eccentric crumbles because it is rotten and brittle.

Our work is as follows:
1/ remove tile adhesive, remove sealant.
2/ cut and chip the rest of the eccentric from the fitting in such a way that small fragments do not fall into the heating pipe.
3/ replace the eccentrics with brass ones in both taps (on the supply and return) and start the heating system.

Lessons learned:
1/ hire craftsmen with contracts so that you have the opportunity to hold the contractor responsible for flooding, for a swollen door and alteration. Poor quality service can be revealed in a few years after the work.
2/ a beam heating system in a private house is more convenient than a one-pipe or two-pipe system, because with a beam system, one of the beams is blocked during the search for help and repairs, and the heating in the house is functioning
3/ install water softeners. pay due attention to water treatment.
4/ brass parts will not be cheap, de-emphasize the price of the goods.
5/ both the supply and return to the heating system must have mud filters, each filter must be finished with ball valves on both sides of the filter, yes, it is more expensive in terms of materials, but then you will not have the floor in the boiler room flooded with water when cleaning the filter (as at this address)
6/ Never install pressed paper doors covered with shiny colored paper or film. If the door leaf, frame or MDF panel absorbs a little water, then the door will instantly swell and then it ... just change it, and you will also have to pick out the DOOR FRAME from the tiles !!! and change the panelka (Imagine that you have buckwheat grain swelled up and turned into buckwheat porridge- are there any means to dry buckwheat to the reverse size of dry grain?). At this address, the door is from natural veneer over natural wood, this can be seen from the photo, so the customer will have to wait until the water dries, but rather they will have to remove the door and deepen the grooves under the canopies by 0.5 millimeters for easy closing, or you may have to remove 1 millimeter door leaf at the bottom of the door.

Oh, by the way, I almost forgot to say:
- you will buy the correct brass parts from us
- masters who work with tiles, doors and plumbing are also with us
- we will bring you the right veneered doors and tiles for your home.

Please buy from us.

Silumin is an alloy of aluminum and silicon. The chemical composition is 4-22% Si, the base is Al, a small amount of impurities Fe, Cu, Mn, Ca, Ti, Zn, and some others. The material is brittle, crumbles during processing without the formation of long flexible chips, unlike aluminum and copper. The disadvantage of silumin is the high porosity and coarse coarse-grained eutectic of castings, which greatly affects the reproducibility (stability) of the strength properties of the parts obtained.

The most ancient alloys used by people are bronze and brass. They differ significantly in their composition, but their scope is similar. Modern alloys are significantly different from those used by our ancestors. Colors and composition of the current metal connections have undergone significant changes over time.

Archaeologists find samples of bronze objects made about 25 centuries ago. These are sculptures, various decorations, armor, weapons, numerous household utensils, dishes, as well as coins. Along with them, brass products were also actively used, which are sometimes very difficult to distinguish from things made of bronze. Acquainted with appearance materials can be on the corresponding photos. To understand how to distinguish bronze from brass or other materials, you need to familiarize yourself with their parameters.

Characteristics of brass

Brass alloy is obtained by combining zinc with copper, to which nickel, iron, manganese, tin, and lead are sometimes added. Typically the material consists of 70% copper component, with 30% zinc component. Almost half of the produced alloy consists of secondary zinc. Technical metal contains about 50% zinc part with 4% lead.

There is also a special type of brass connection called “tompac”. In it, the copper component reaches 97%, and zinc - from 10 to 30%. From this compound, excellent jewelry, various art products, insignia, and accessories are obtained.

A couple of centuries ago, brass alloys were often used as counterfeit gold, which was achieved by using pure zinc rather than ore. Such a connection was very difficult to recognize by inexperienced users. It has become widely used in various industrial fields thanks to unique properties. These alloys have high ductility, abrasion resistance and good corrosion resistance.

The difference between copper and brass

Copper has features that make it popular in the manufacture of various decorative elements. In addition, it has good electrical parameters, as a result of which it is used in the manufacture of electrical apparatus. At home, there are several ways to distinguish copper elements from brass ones.:

color;
hardness;
marking;
area of use.

Color

To determine the metal, it should be cleaned. metal surface is freed from contaminants with a solution of plain water with vinegar. This removes not only dirt, but also an oxidizing film. Under a white light source, the product being tested is carefully examined. A brass thing differs from copper by a simple visual observation. A copper object will have a brownish-red color of a uniform appearance, while brass will look lighter, with multi-color tints. This heterogeneity indicates the presence of several metals in the composition, which determine the color shade. Identify copper under lamp yellow color or in daylight it is practically impossible.

Hardness

To understand how to distinguish copper from brass, you should tap them lightly. A copper product makes a muffled sound when it hits a hard area. This is due to the special softness of the metal. Brass objects are characterized by a sharp, ringing sound of impact. This check is used for large items.

Marking

Some items have special markings on their surface. For brass products, the letter "L" is used. On copper elements, the designation is practically not put. Some parts may be marked with the letter "M" with a numerical addition. In this case, special reference books are used to determine the specific composition of the material.

Application area

Distinguish between these materials and the area of use. Brass alloys are often used for the manufacture of various constituent parts, details. Copper is an ideal element for the production of electrical wires and other electrical parts. This is due to its excellent electrical parameters.

The difference between bronze and brass

Bronze, like brass, is based on a copper component. Some grades of these alloys have a similar color parameter, but completely different properties. The bronze item has a structure of a coarse-grained type with a dark brown or reddish tint, in contrast to yellowish brass with a fine-grained form. It should be taken into account that the presence of tin in the bronze alloy in in large numbers gives it almost White color. Modern compositions contain an alloying tin component or any other (beryllium, lead, aluminum, silicon with zinc). Numerous things made of brass and bronze have differences, which can be determined by knowing their technical parameters.

Metal objects made of brass and bronze are distinguished by weight. A bronze item is heavier than a brass one, however, before determining the alloy, it is necessary to take items of approximately the same size for comparison. To determine what material a thing is made of, you must try to bend it. A brass object can succumb slightly, and bronze can break. You can try to make a small saw with a hacksaw, in which the bronze part will give small chips. It will not change its characteristics when heated.

To understand how to distinguish brass from bronze, you can apply chemical method. A small number of chips of both alloys are placed in different glass containers with dilute type nitric acid (parts 1 to 1). It is necessary to wait some time so that the bulk of the metal has time to dissolve in chemical composition. The liquid that does not reach a boil is kept on low heat for half an hour. In the composition with bronze shavings, a whitish tin precipitate is formed.

Bronze is used for the manufacture of large items, as it is more resistant to abrasion. In addition, a variety of marine accessories are also made from this alloy, which is not afraid of exposure to salt water, is not subject to oxides and does not rust.

The difference between silumin and brass

The silumin material consists of an aluminum base with the addition of silicon, as well as a small amount of copper, iron, and manganese. It has good wear resistance and strength in relation to aluminum things. The difference between silumin and brass is brittleness this material and application features. They are used for casting many products used in various fields, including for household goods, as well as for the manufacture of costume jewelry. Silumin object is characterized by high porosity and low strength. During processing, silumin begins to crumble, which clearly distinguishes it from brass things.