Powder manufacturing technology. Raw materials for making washing powder

Powders - solid dosage form for internal and external use, consisting of one or more crushed substances and having the property of flowability.

There are simple powders (boric acid, potassium permanganate, magnesium sulfate) and complex (licorice powder, Karlovy Vary artificial salt, powders for children, amikazole, galmanin).

Classification:

1.for internal use (LF from solid individual dry particles of various degrees of grinding, with the property of flowability):

· M. B. dyes, flavors;

2.for external use (LF from solid individual dry particles of varying degrees of grinding, having the property of flowability):

· M. B. single and multi-dose;

3.Effervescent:

· M. B. single and multi-dose;

· For dissolution in water;

4.for inhalation:

· M. B. single and multi-dose;

· For more efficient use of them DV d. B. mixed with a carrier;

· Are used with an inhaler;

5. for the preparation of injectable drugs and infusions (sterile solid substances placed in appropriate containers and, when an appropriate sterile liquid is added, forming a transparent and particle-free solution or a homogeneous suspension) (often lyophilized powders);

6. nasal (for introduction into the nasal cavity through a suitable device);

7. powders and granules for the preparation of syrups, solutions, suspensions.

Requirements:

Grinding of DV and auxiliary;

Looseness;

Stability;

Uniformity of the AR content (for single-dose powders for internal use with an AR content of less than 2 mg or 2℅ of the total weight;

Mass homogeneity (for single-dose powders for internal use; if OSDV was carried out, then it is not used).

Powder production diagram

BP1.2. Staff training

TP1. Shredding → loss

TP2. Sifting → loss

TP3. Mixing → loss

TP4. Sifting → loss

TP5. Dosing → losses

TP6. Standardization

Shredding - the process of mechanical division of solids into parts, as a result of which the surface area increases, the degree of dispersion, which ultimately leads to an increase in biological effects.

Grinding goals:

· To achieve uniform mixing of all components;

· To eliminate large aggregates, clumping and sticking materials;

· To increase biological and technological effects.

Grinding methods(depending on the physicochemical properties of the crushed material):

Crushing (mechanical force is applied from above);

· Blow (from above with a jerk);

· Abrasion (from above and from the side progressively);

Splitting (suddenly above and below);

· Sawing (with teeth at an angle progressively);

· Cutting (from above with a jerk);

· Breaking.

If the material hard and brittle, then use the methods of crushing and impact; hard and viscous- crushing and sawing; for brittle and medium hardness- impact, splitting, abrasion; for tough and medium hardness- abrasion, sawing, abrasion and impact.

The initial drugs are ground to the optimum degree of grinding, depending on the purpose of the finished product (crystalline substances for making solutions - 0.2-0.3 mm, powders - 0.09-0.093 mm, if the degree of grinding is not specified - no more than 0.160 mm). Some materials (waxes, resins, gums, solid fats) are ground with cooling - to increase the fragility of the material, some (camphor, boric acid) - with the addition of alcohol or ether.

Grinding machines (shredders) are classified into:

1) Mills (fine and ultrafine grinding) and crushers (coarse, medium and fine grinding).

2) Machines for pre-crushing and ashina for final crushing.

3) By grinding method:

Ripping and sawing action (grass cutters, root cutters, machines with circular knives);

Splitting and crushing action (jaw crushers);

Crushing action (roller crushers);

Abrasive crushing action (disk mills, "Excelsior");

Impact type (hammer, jet mills, disintegrators, dismembranators);

Shock-abrasive action (ball and drum mills);

Colloidal grinders (vibration and jet mills).

Screening has the purpose of separating the crushed material into fractions with the same particle diameter.

Screening machines are divided into:

Wicker sieves and stamped sieves;

Swinging, drum and vibrating (inertial, hygration, electro-vibration) sieves.

Mixing - a mechanical process that ensures the distribution of particles of one solid material among particles of other or other materials.

In factory powder technology, the following principles are used:

If the substances of lists A or B are included in the powder in small quantities, then they are crushed beforehand

Substances of lists A or B are mixed with excipients (lactose monohydrate)

The substance prescribed in a very small amount is preliminarily dissolved, the powder mass is sprayed, mixed, dried

Mixing starts with the smallest prescribed ingredient.

Mixers: bladed, auger, "drunken barrel".

Dosage is carried out according to a given volume corresponding to a certain mass of powder with dispensers of various designs: screw, chamber vacuum.

For packaging multi-dose powders use polymer containers, single-dose - paper bags.

Collection - a mixture of several types of crushed, less often whole medicinal plant raw materials, sometimes with admixtures of salts, essential oils, etc.

Classification:

1) Simple and complex

2) Non- and metered

3) Non- and extruded

4) By method of application: for internal, external, inhalation use

Charge production scheme

BP1 → BP1.1. Preparation of premises

BP1.2. Staff training

BP1.3. Equipment preparation

BP1.4. Pharmaceutical preparation. substances, auxiliary substances

TP1. Shredding → loss

TP2. Sifting → loss

TP3. Mixing → loss

TP4. Adding essential oils and salts (not always)

TP5. Dosing (not always) → losses

TP6. Standardization

At shredding MP must take into account the localization of DV and the orphological and anatomical structure (for example, belladonna leaf veins are poorly powdered, they cannot be discarded, but you need to achieve maximum grinding, since there are most alkaloids). The medicinal product should be crushed without residue, because the distribution of DV in plant tissues is uneven. Usually medicinal plant raw materials are also dried to a residual moisture content of 6-8%.

In the preparations for the preparation of infusions and decoctions, the degree of grinding is established: leaves, flowers, herbs no more than 5 mm (bearberry no more than 1 mm); stems, bark, roots, rhizomes no more than 3 mm; fruits and seeds no more than 0.5 mm. In preparations for baths, poultices and in emollient preparations, the degree of grinding is 2 mm.

For grinding, jaw and hammer crushers DM-400, dismembranators and disintegrators using splitting, grinding, impact action (roots of rhubarb, soapwort, eleutherococcus, chaga, viburnum bark, rhizome of zamaniha, fern), grass and root cutters (plantain leaf, rhizomes valerian).

At salt administration they are dissolved in a minimum volume of water, the collection from a spray bottle is sprayed with the resulting saturated solution, then dried in an oven at 40-60 ° C. If the collection includes a significant mass of salt, then one of the vegetable ingredients of the collection (preferably with mucous substances) is selected, it is moistened with water, sprinkled with salt powder, and dried. The hygroscopic raw materials are added to the harvest last, after spraying and drying. Essential oils dissolve in alcohol 1:10, spray the collection, dry. After drying, the mass of the collection should be equal to the mass of all ingredients excluding solvent.

Fees pack in boxes lined with parchment paper, or in a double paper bag of 50, 100, 150, 200 g. The composition and preparation method are indicated on the package.

9. Characteristics of tablets. Types of tablets, technological requirements for them. Quality control. Characteristic subsidiary

A tablet is a solid dosage formulation of Lf containing 1 dose or more in its composition. - c, obtained by direct tableting of auxiliary and acting in or using granulation.

T. There are different shapes (flat, flat-cylindrical, doubly convex, etc.), different diameters (4-25 mm, if the diameter is more than 9 - there is a risk on the surface (notch), the height should be 30-40% of the diameter ).

Classification: A) by purpose.

1. For oral administration: DV are released in the oral cavity (sublingual T, T for sucking, cheek, for biting, for chewing, for a tooth socket); T for swallowing (DV is released in the stomach; in small intestine; T with modified release rate); effervescent T and T for diagnostic purposes.

2. For introduction into the body cavity (vaginal, rectal)

3. For extraintestinal use: T for the preparation of RDI, T for implantation.

B) Depending on the presence of the sheath: covered and uncoated.

C) depending on the dose of DV: mite is the minimum dose of DV for a minimally pronounced therapeutic effect, semi is an average, forte is the maximum dosage for a large therapeutic effect.

Technological requirements.

1. Looseness - the ability of a powdery mass to pour out of a container or flow under its own gravity and thereby ensuring uniform filling of the matrix channel.

2. Compressibility - the ability of a tabletted powder under the influence of pressure to take and maintain a certain shape and size of a tablet.

3. Bulk weight - the mass of a unit volume of free bulk powder material.

4. Relative density - characterizes the packing density of particles in the powder and is the ratio of the density of the powder to the density of the compact material and is expressed in%.

5. Porosity is the volume of free space between powder particles. It is determined based on the values ​​of the bulk and true density.

Quality control.

Uniformity of the content of DV in a unit of dosed solid drug - for T with an DV content of 2 mg or less or less than 2% of the tablet weight. (The content of DV in each selected unit is 85-15% of the average content of the minerals)

Disintegration - the time during which the tablet is immersed in the corresponding liquid to disintegrate / dissolve, and no tablet particles remain on the calico with an average hole diameter. (T without a shell - not b. 15 minutes, T for sucking 15-60 minutes, T PO - not b. 30 minutes, T enteric-soluble - do not disintegrate in acid for 120 minutes, in alkali - not b. 60 minutes)

Dissolution (can be used to assess bioavailability) - the amount of DV, which, under standard conditions, over a certain period of time will go into solution from the solid dosage form of the drug. (70-115% DV of the content specified in the "Composition" section should go into the solution).

Abrasion resistance (for T uncoated). Less than 0.65g - 20 tablets, 0.65 and more - 10 tablets. There should be at least 99% of the mass after 100 revolutions in the apparatus.

Compressive strength - by measuring the force required to break the tablets. (depends on the diameter)

Auxiliary islands.

Klichstvo d.b. the minimum possible. D. meet the appointment of LF. Show your properties as much as possible. D to ensure the manifestation of the necessary pharmacological action of DV, taking into account their famakokinetics. D. b. technological. Do not have toxic, irritating and allergic effects, do not interact with DV, with materials of the container, with technological equipment... D. have chemical and bacteriological purity. Wherever possible, be economically affordable.

The role is to provide the required mass and volume, contribute to the successful implementation of the technological process, and ensure the bioavailability of the DV.

From the function performed: lubricating component (hydrophobic), granulating, hydrophilic filler and disintegrating.

From destination: linking(purified water, starch paste, sugar syrup), loosening(swelling - starch, pectin; gas-forming - sodium carbonate and bicarbonate; improving wettability and water permeability- starch, lactose), antifriction(sliding - starch, talc, aerosil; anti-stick - stearic acid, talc), fillers(diluents - glucose, dextrin, mannitol).

10. Comparative characteristics tablet machines. Double pressing machines.

Machines: skid, intermediate (shoe) and rotary.

Sled- the composition of the hopper, which moves when the machine is running on a special slide. Main e-you: matrices and punches. The die is attached to the die table and is limited from below by the lower punch. Pressing is carried out by the upper punch according to the impact type.

Shoe- are close to sled ones in design and principle of operation. They differ from them by the immobility of the loading funnel. Filling - with a movable shoe. Upper punch pressing.

Rotary- composition of a matrix table with matrices. Upper and lower punch on pressing rollers. The hopper is stationary. Pressing occurs simultaneously with the upper and lower punch. (RTM-12; 41; TP-40M, “Drycota”).

"Drycota" - for the production of multilayer tablets, for the production of coated tablets by pressing.

RTM-24D - for producing facing tablets, consists of two rotary machines connected by a transporting device (the first rotor for producing a tablet core)

Powder-crushing shops (departments) pharmaceutical companies In addition to meeting the needs of their enterprise (tablet shop, shop for extraction preparations), they produce a large number of powders for pharmacies. Basically, these are powders of plant origin (powders of leaves, roots, seeds, etc.), which are necessary in everyday recipes for the preparation of powders, pills, suppositories, etc. Along with this, enterprises produce a significant amount of complex powders according to prescriptions regulated by the FS , VFS or MRTU.

Features of factory production of powders

The production of powders in the factory consists of the same operations as when preparing them in a pharmacy. However, due to the large quantities and volumes of raw materials used and specific properties (many of them), which are especially evident when processing large quantities, factory production of powders has its own characteristics.

Powder forging

When powdering plant materials and other materials, the essential issue is the correct choice of the machine. First of all, it is necessary to take into account the strength of the crushed material, understanding it as its ability to resist destruction under the influence of external forces. Obviously, crushing rhubarb rhizomes will require some effort, and crushing sugar - others, incomparably less. In the first case, runners or a hammer mill are needed for grinding, while in the second, a disintegrator or a ball mill will be sufficient.

When powdering plant materials, it is necessary to take into account the morphological and anatomical features of the plant and the localization of active substances in it. Obviously, for fibrous roots (for example, marshmallow) one type of machine is required, and for non-fibrous (rhizome and valerian roots), another.

The moisture content of the crushed materials is of great importance in the preparation of powders of plant origin. It should be borne in mind that plant raw materials with a commercial moisture content provided for by GOST and pharmacopoeial articles are poorly powdered. Raw materials must be dried to a residual moisture content of about 6-8% (instead of the usual 12-14%). Drying is carried out in dryers taking into account the morphological and anatomical features of the raw materials and the stability of the active substances contained in it.

Finally, the choice of machine depends on the desired fineness. When determining it, proceed from the instructions of the GFC.

Dusting medicinal substances that form toxic or highly irritating dust(arsenous anhydride, Spanish fly, emetic root, etc.). In this case, the least dusty machines are used, most often ball mills. Powder coating is carried out in separate rooms. Machines are covered with casings, cases, covers. It is necessary to take personal safety measures (respirators, overalls).

Powder coating with cooling. When powdering soap, resins, ca-copper, waxes, solid fats, cooling is necessary to increase the fragility of substances. Grinding is carried out in disintegrators and hammer mills with the supply of cold air after pre-cooling in the refrigerator of the products themselves.

Powder coating after preliminary degreasing. The presence of fatty oil in objects due to its rancidity worsens the preservation of powders (for example, ergot). The oil is removed from the coarse powder by extraction with gasoline in a Soxhlet-type apparatus, after which the final powdering is carried out.

Powder after preliminary softening. It is used for seeds of chilibukha and salep tubers, the tissues of which need preliminary separation (separation from each other). Chilibuhi seeds are exposed to steam and hot water, after which they are cut into thin pieces, dried and only then powdered in a ball mill. Salep tubers are macerated with cold water, cut, dried and then powdered.

Powder coating with auxiliary substances. Substances that are difficult to powder directly are mixed with some grinding aid. With the addition of solids (sugar), for example, vanilla is powdered (sugar absorbs the moisture of vanilla). With the addition of liquid substances (alcohol, ether), camphor and boric acid are powdered.

Mixing. Joint grinding and mixing

The main issue in the preparation of complex powders is the uniformity of their mixing. A convenient way is joint grinding on runners, disintegrators, dismembrators and ball mills. Along with this, mixing is carried out in mixers. Drum mixers are most commonly used. In its simplest form, it is a cylindrical or multifaceted closed drum driven in rotary motion. In ribbon mixers, mixing is carried out by curved steel strips (belts) that move the materials to be mixed in a closed trough-shaped vessel from one end of the apparatus to the other. The plant material is mixed in two opposite directions due to the fact that the bands (two) are bent along the right and left helical lines. In addition, the material lifted by the rotating belts falls back into the mixing mass in the wrong place where it was taken from, which significantly contributes to homogenization. Werner-Pfleider machines with two sigmoid blades are also suitable for mixing powders. The substance lifted by one blade upwards, the other is directed downwards.

Screening

Sifting of one-component powders is carried out on the sieve mechanisms described on p. 76. GPC for most plant powders regulates not only the degree of grinding, but also the limiting amount of particles that do not pass through sieves with holes of specified sizes.

As for complex powders, the homogeneity of the mixture during sieving may be disturbed due to the stratification of the components, therefore the latter are sieved separately and only then mixed.

Dosing and packaging

In the factory, the operations of dosing and packaging of powders are combined production process and are carried out on one production line. Filling machines for powders work by volumetric and weighing methods. The simplest machine, the operation of which is based on the volumetric method, uses a screw for dosing, the number of revolutions of which regulates the amount of powder poured out. There are no valves in piston dosing machines for powders, the cylinder itself with a piston rotates.

With a volumetric filling method, high accuracy cannot be achieved, since at the slightest shake of the dispenser, the mass easily changes (due to a denser packing of powder particles).

The weighing method is used in automatic scales (fig. 124). The main part of the scale is a rocker /, on one side of which a cup is suspended 2 for weights, and on the other - a dosage cup 3. Before putting the balance into work on the pan 2 place weights and finally set the mass of powder with the regulator 8 with movable weights 15 and22, and also fill the hopper with powder 4. Then the scale is operated with the handle. 17, which through the levers 6 and 7 opens the damper 10, and the powder begins to fill the balance through channel 5 3. As soon as the required mass has been reached, the arrow 18 touches the zero division of the scale - screw 21 through the levers 6 and 7 and flap 20 closes the damper 10. Simultaneously with levers 12 and 13 folds back the bottom of the cup 3 and a dose of powder is poured out through the funnel 14. Under the action of a counterweight 2/3 of the bottom of the cup 3 closes, the scales are out of balance, With using a screw 19 through the levers, the damper opens again 10 and the process is repeated. Regulator and rocker oscillate on a prism 16. The speed of the powder flow from the hopper is regulated by a flap 9. The balance can be temporarily stopped with lever 11 . The handle is used to stop the automatic scales. 17.

Private technology and nomenclature of powders

The industry produces from complex powders:

Complex licorice powder(Purvis Glycyrrhizae compositus). Composition (parts) according to GFH: licorice root and senna leaves - 20 each, fennel and sulfur - 10 each, sugar - 40. Powders of these substances are mixed in a mixer, sifted through a sieve with holes with a diameter of 0.2 mm and mixed again.

Artificial Karlovy Vary salt(Sal. Carolinum factitium). Prepare by mixing 44 parts of dried sodium sulfate, 36 parts of sodium bicarbonate, 18 parts of sodium chloride and 2 parts of potassium sulfate.

Alkaline salt rinse(Gargarisma alcalina). Consists of 5 parts of sodium chloride, 10 parts of sodium bicarbonate and 15 parts of sodium tetraborate.

Amikazole powder(Aspersio Amycazoli) 2 and 5%. For the first time, the recipe is included in the GFH. Filler - talc (98 and 95%) - Antifungal agent; List B.

Galmanin(Galmaninum). The composition of this disinfecting and drying powder includes: salicylic acid 2 parts, zinc oxide 10 parts, starch and talc in 44 parts.

Man has always strived for cleanliness, starting from ancient times, when people rinsed their clothes in rivers, and up to today, when in most cases machines take over this responsibility.

Of course, initially no one knew about detergents in their modern understanding, they used exclusively natural products and water. Soap appeared later, and in 1876 the first production in world history was created. washing powder... The manufacturer was the German factory Henkel & Cie headed by Fritz Henkel.

Our days: the powder market in Russia

Many years have passed since then, and the number of manufacturers has increased to hundreds of thousands around the world. There are certainly leaders among them. And in our country they are foreign companies, which occupy up to 80% of the entire Russian market.

Domestic large manufacturers of washing powder in Russia have a small share - about 10%. The remaining 10% is accounted for by small firms and is ideal for entry of newcomers who want to take their niche in this segment of detergents.

Of course, it is not easy to fight the giants of the market, which, moreover, have long won the trust of the majority of consumers. However, it is quite possible to win over some of them to your side. To do this, you need to prove yourself from the best side according to three main criteria: efficiency, safety and availability. Learn how to set up a powder making business in this article.

The range of basic questions on the organization of powder production

The production of washing powder is a rather complicated process from the point of view of technology, therefore, it requires a competent approach. This is due to the large variety of chemicals used to create it. Due to the multicomponent and the correct combination of elements, the detergent is able to effectively remove dirt without affecting the quality of the fabric. Thus, the main issues that need to be carefully thought out and properly organized are the technology and equipment for the production of washing powder. In addition, you must:

• choose a suitable room for a workshop / plant;
• collect the necessary permits;
• determine the sales market and think over a marketing strategy.

Technology: how and from what to produce

The composition of the washing powder is distinguished by a variety of components. Almost all products on the market are made from the same chemicals, and the difference is due to the combination of various ingredients in certain proportions, which directly affects the quality of the finished product.

The correctly selected percentage determines how effectively the powder will remove stains, whether it will gently affect the quality of fabrics, their color, etc. In this matter, the role of a chemist is great. Therefore, make sure that there is a competent and experienced specialist in your production.

Chemical composition of washing powder: list of ingredients

As for the main components, most of the washing powders contain the following substances:

• surfactants - separates dirt from fabric (synthetic substances, soap);
• binding - eliminate water hardness, provide softness to fabrics, prevent the formation of scale in the washing machine (phosphates or, if they are phosphate-free washing powders, zeolites);
• whitening - due to the oxygen content, they give freshness to tissues, remove plant stains on clothes (sodium perborate, etc.);
• lipases - break down fatty impurities, amylases - starch, alkaline proteases - protein;
• anti-resorbents - prevent re-contamination of fabrics during washing, keeping the removed dirt in the solution;
• auxiliary - give freshness to linen, neutralize an unpleasant odor during washing.

Thus, in today's powder industry, as a rule, synthetic substances are used - perzolates. If detergent is intended for washing children's clothes, then soap shavings are usually added to its composition. It is absolutely harmless and environmentally friendly.

If the powder is intended for use in a washing machine, then defoamers are a mandatory component. These substances suppress the formation of foam during washing. V Lately phosphate-free washing powders, in which phosphates are replaced by zeolites, citrates and other harmless components, are becoming more and more widespread. The result is a product that is completely safe for environment and a person.

Raw materials for making washing powder

Raw materials for the production of powder are not cheap, but they are quite affordable. The chemical industry is well developed in our country and it is not so difficult to find domestic suppliers for a plant that is starting its work. If we talk about cost, then on average the price tag in Russia is as follows (per kilogram):

• sulfanol powder - about 100 rubles;
• surfactants - 80 rubles;
• soap shavings - 45 rubles.

Naturally, these are just the main components. There are many others, additional ones, which will also have to be purchased. However, the cost of one pack (500 grams), as a result of their combination, will be low.

Manufacturing process: powder preparation steps

We talked about the composition. What is the technology for the production of washing powder? It is from her correct organization and the success of the end result will depend. As mentioned earlier, the most important difference between products different manufacturers- not used components, but their combination with each other. It determines the good (or not so) composition of the powder and determines its quality characteristics. For example, some components enhance each other's action, while others reduce it. The formulation development process should take place in conjunction with competent chemists.

If we talk about the sequence of actions in the manufacture of powder, then it is as follows:

1. The paste resulting from the sulfonation of akibenzene combines with the rest of the heat-resistant ingredients.
2. The resulting mass is sprayed through the nozzles of the spray drying tower.
3. The hot air-dried droplets are converted into powder granules.
4. Next, the powder mass is mixed with non-heat-resistant ingredients (perborate, enzymes, etc.).
5. As a result of all these processes, washing powder is obtained, which is sent to packaging.

The production of powder itself is a fairly clear and well-defined process. The main thing is to successfully develop the composition of the detergent.

Powder compositions can be produced from metals and various alloys. They can be used in a wide variety of ways to protect workpieces and parts. Powder metallurgy is an actively developing field that has a huge number of features. This direction of metallurgy appeared over a hundred years ago.

Powder production

For the production of powder, a variety of technologies can be used, but they are united by the following points:

1. Profitability. Waste from the metallurgical industry can be used as raw materials. An example is dross, which is not used anywhere today. In addition, other wastes can be used.
2. High accuracy of geometric shapes. Products obtained using the considered technology of powder metallurgy have precise geometric shapes, no further mechanical processing is required. This point determines a relatively small amount of waste.
3. High wear resistance of the surface. Due to the fine-grained structure, the resulting products have increased hardness and strength.
4. Low complexity of powder metallurgy technologies.

Considering the most common technologies of powder metallurgy, we note that they are divided into two main groups:

1. Physicomechanical methods consist in grinding raw materials, due to which the particle size becomes small. Manufacturing processes of this kind are characterized by a combination of different loads that affect the raw materials.
2. Chemical and metallurgical methods are used to change the phase state of the raw materials used. An example of such production is the reduction of salts and oxides, as well as other metal compounds.

In addition, we highlight the following features of powder production:

1. The ball method involves processing scrap metal in a ball mill. Due to careful crushing, a fine-grained powder is obtained.
2. The vortex method involves the use of a special mill, which creates a strong air flow. The collision of large particles produces a fine powder.
3. The use of crushers. The load that is created when a heavy load falls, leads to crushing of the material. The shock load acts with a certain frequency, due to which the composition is fragmented.
4. Spraying raw materials in liquid form under the influence of compressed air. After receiving a brittle composition, the metal is passed through special equipment, which grinds it to obtain a powder.
5. Electrolysis is the process of recovering a metal from a liquid composition under the influence of an electric current. By increasing the brittleness index, the raw material can be quickly ground in special crushers. This processing method makes it possible to obtain dendritic grains.

Some of the above technologies of powder metallurgy have become widespread in industry due to their high productivity and efficiency, others are practically not used today due to the increase in the cost of the raw materials obtained.

Compacting

Powder metallurgy also provides for a procedure that is based on the production of semi-finished products in the form of bars and strips. After pressing, an almost ready-to-use product can be obtained.

The features of the compacting process include the following points:

1. A free-flowing substance is used as a raw material for the process under consideration.
2. After passing through compaction, the free-flowing powder becomes a compact material with a porous structure. The strength of the resulting product is acquired in the course of other processing processes.

Considering the process of pressing the powder, we note the use of the following technologies:

1. rolling;
2. slip casting;
3. isostatic pressing by applying pressure with a gas or liquid;
4. pressing from one or both sides using special metal dies;
5. injection method.

In order to speed up the compaction process, the powder is subjected to high temperatures. In most cases, the distance between individual particles is reduced by exposure to high pressure... Powders made of soft metals are highly durable.

Sintering

The final step in powder metallurgy is high temperature exposure. Almost any powder metallurgy method involves exposure to high temperatures. Sintering is carried out to achieve the following goals:

1. to increase the density of the product;
2. to impart certain physical and mechanical qualities.

For thermal exposure, special equipment is being installed. The protective environment is usually inert gases such as hydrogen. The sintering process can also be carried out in a vacuum to increase the efficiency of the applied technology.

The induction heating method is also very popular. It provides for the use of induction furnaces that are manufactured or made by hand. There is equipment on sale that can combine several technological processes: sintering and pressing.

Application of powder metallurgy products

Powder metallurgy is used in aviation, electrical engineering, radio engineering and many other industries. This is due to the fact that the applied production technology makes it possible to obtain parts of complex shapes. Besides, modern technologies powder metallurgy makes it possible to obtain parts with:

1. High durability. The dense structure provides increased strength.
2. Durability. The resulting products can serve in harsh operating conditions for a long period.
3. Wear resistance. If you need to get a surface that does not wear out under mechanical stress, then you need to consider the technology of powder forming.
4. Plasticity. You can also get workpieces with increased ductility.

Also, the spread of this technology can be associated with the low cost of the resulting products.

Advantages and disadvantages
The method of obtaining products from powders has become quite widespread due to the large number of advantages:

1. low cost of the resulting products;
2. the ability to produce large parts with complex surfaces;
3. high physical and mechanical qualities.

The metallurgical powder method is characterized by several disadvantages:

1. The resulting structure has a relatively low strength.
2. The structure is less dense.
3. The technologies under consideration provide for the use of specialized equipment.
4. If the production technology is violated, the parts are of poor quality.

Today powder metallurgy is actively used in various industries. In addition, developments are underway that are aimed at improving the quality of the products obtained.

In conclusion, we note that when small particles of various metals and alloys are combined, materials with special performance are obtained.