Many patients who have had a heart attack, as well as their relatives, ask the doctor the question: how many years can one realistically live after such an attack? But it’s difficult to give an exact answer; there are many reasons for this. The first and most important aspect is age. Old people are less likely to survive up to 10 years after a heart attack, because it is often accompanied by other diseases. For young people, the chances are more encouraging. There are other important points that should also be taken into account.

After an attack, the most difficult and significant in terms of life expectancy are the first month and a year later.

What determines life expectancy?

Aspect two, which is directly related to the length of years – kinds . They are divided into early and late. If the lesion is small, then there will be fewer complications.

Early consequences:

1. Pulmonary edema.
2. Heart rhythm failure.
3. Acute heart failure.
4. Thrombosis.

Most often, the disease affects the left ventricle of the heart, which is why failure occurs in this department. Its characteristic symptom is breathing problems. Forms of heart rhythm disturbances are also dangerous. Doctors say that long-term complications are not as dangerous to health as acute ones, but they appear much more often.

Late complications:

1. Cardiosclerosis.
2. Pleurisy.

Cardiosclerosis is a characteristic disease for all heart patients, and directly affects life expectancy after an attack. This condition is associated with how quickly the cardiac scar heals; in the diffuse form, deviations in the activity of the heart muscle begin.

A separate list includes complications during the death of heart cells:

1. Thromboembolism.
2. Thromboendocarditis.
3. Rupture of one of the ventricles.

So, the maximum opportunity to live after a heart attack for a long number of years remains for patients whose health is not complicated by other diseases and unpleasant consequences. If you follow the recommendations during recovery, it is quite possible to significantly reduce the risk.

A procedure such as stenting, when the walls of the arteries are cleared of atherosclerotic plaques, also prolongs the life of heart attack patients. The blood flow is restored, the heart continues to work without overstrain.

If the patient copes with an attack at 60-80 years of age, the mortality rate in the first year after the attack is 35%.

How long do they live depending on the type of heart attack?

The first recommendations of doctors are to protect the patient from severe stress. Fear, joy, fright - any shock can become fatal for the body, even with positive prognosis. If such nervous shocks have happened often in the past, and promise to happen in the future, it is problematic to talk about the patient’s long life expectancy. But in their assessments, doctors also take into account the forms of the disease.

After a micro-infarction

Most often it occurs in men, starting from the age of 30, women last longer. In addition, they rarely pay attention to the symptoms of the disease, attributing it to general malaise or fatigue. Meanwhile, the consequences are no less dangerous, since the next stage may be a heart attack.

Characteristic features:

• pain behind the sternum, radiating to left hand;
• , feeling of lack of air;
• heart rhythm disturbances.

With proper treatment, it is possible to recover and live for more than one year. The patient does not feel any sharp restrictions after a microinfarction; only strong physical activity and stress are prohibited.

After a heart attack

After a heart attack, recovery is much more problematic, because part of the heart tissue dies. When a large part of the organ suffers, it affects the general condition of the patient. According to statistics, the process of destruction in most heart attack patients is observed in the right ventricle. If necrosis covers up to 10 cm in width, blood flow in the coronary artery is severely impaired.

The statistics of life after a heart attack are very sad. Only if the assistance was provided competently and at a high level, we can talk about good chances. If a person lives for 10 years after an attack, then his life expectancy is equal to that of a healthy person.

Studies have proven that if a patient survives a month after the first attack, the chances of surviving another year are 85%, the probability of up to 5 years is estimated at 70%.

The second attack is much more dangerous, most often occurring in sufferers. This disease is detected in all heart attack patients and is often accompanied by asthma and heart rhythm disturbances. This time the symptoms will be less noticeable, since the affected organ reacts much weaker. In 80% of cases, a repeated heart attack is provoked by atherosclerosis.

Symptoms:

• pain radiating to the arm;
• severe suffocation;
• pressure decreases;
• fainting.

It is difficult for doctors to predict whether there will be a relapse or not, since it depends on the general health of the patient and how well he follows his diet and daily routine. A distinction is made between repeated and recurrent infarction. In the first case, a heart attack may occur a couple of months after the first one. In case of relapse, this may happen earlier. Moreover, the survival rate after a second or recurrent heart attack is low.

To avoid such manifestations and live for more than one year, you must try to reduce the amount of bad cholesterol in the blood and on the tongue. medical terms– low density lipoproteins. Drug treatment and traditional methods will help with this.

Extensive myocardial infarction affects all layers of cardiac muscle tissue, epicardium, myocardium, and endocardium.

Risk factors

There are a number of factors that affect how long a person can live after an attack.

In this list:

1. Nature of the disease. Some people have one large scar on their heart after a heart attack, while others have several small ones.
2. The appearance of atherosclerotic plaques that block the arteries.
3. In men, cardiovascular diseases are caused by a lack of large quantity estrogen in the blood, which is why heart attacks occur more often in them than in women. But this situation is typical only up to 70 years of age, then the incidence rate is the same.
4. Diabetes or excess weight, which greatly overloads the heart muscle.
5. Heavy loads during the recovery process.

How to maximize life after a heart attack?

It is difficult to give an exact figure for how many years people live after a heart attack, since personal, characteristics organism, severity of the disease, heredity.

Helps the body return to normal, live for several years with a competent menu and giving up alcohol and cigarettes. You also need to regularly do special exercises; swimming and walking can help restore recovery. But all physical activity is only on the recommendation of a specialist.

To maximize your life after an attack, you need to avoid stress and other tangible stress.

It is difficult to predict the chances after a heart attack; it all depends on how sensitive a person is to his health. It is very important to undergo diagnostics on time and consult with specialists. If the disease is recognized at an early stage, such a patient has a much greater chance of recovering quickly and without consequences.

The heart and brain are more closely connected than previously thought. The devastating effects of myocardial infarction also affect the brain. In fact, a heart attack causes the death of neurons in the brain stem, which leads to insomnia.

Sleep plays a crucial role in rehabilitation after a heart attack, according to scientists from the University of Montreal.

During the two weeks following myocardial infarction, periods of paradoxical sleep were observed less frequently and did not last long. This phenomenon occurred due to the death of cholinergic neurons that control paradoxical sleep as a result of apoptosis or programmed cell death.

A previous study by Goodbot and Russo's team found that myocardial infarction affected the limbic system, which controls mood. This explains the depression that is often observed after heart attacks. Since depression is often accompanied by insomnia, the scientists wanted to test whether there was damage to neurons in the brain stem.

It turned out that myocardial infarction causes not only depression, but is also associated with the action of factors that generate inflammation of tissues such as the brain, especially in the areas that control sleep and its paradoxical phase. The specific function of this phase activates the areas of the brain responsible for the integration of emotions. This is how the risk of depression increases.

Poor sleep is a known risk factor for cardiovascular disease. Therefore, insomnia can worsen rehabilitation, cause complications, and increase the risk of relapse.

An excellent way to improve sleep are herbal sedatives, consisting of several plants. For example, one of the collections involves three ingredients - oregano, tansy and calendula. Take equal amounts of all dried herbs; for half a liter of water you will need a large spoon of the mixture. The drink is prepared in the usual way - the collection is poured with boiling water, infused and then filtered. Drink half a glass three times a day.

Sometimes, due to anxiety, it is very difficult for a person to fall asleep, in which case another calming herbal mixture will come in handy. St. John's wort, hop cones, chamomile, mint and lemon balm are mixed. A teaspoon of the mixture is brewed in a thermos for two hours; after straining, a healthy drink is ready. It is advisable to drink it in three doses before bed. This tea will allow you to relax and fall into a restful sleep.

A good night's sleep will come from a mixture of water trefoil, valerian and peppermint. The herbs should be crushed and mixed, then a spoonful of the mixture is poured with boiling water and infused in a thermos. The drink will be ready to drink in half an hour. You need to strain it and take half a glass before bed. It is advisable for nervous people to drink this tea two or three times a week; it is very calming, but it should not be consumed in the morning, as it may cause drowsiness and lethargy.

If you need to relieve nervous tension, soothing herbal teas containing cumin, valerian and chamomile are used. The drink prepared in the usual way should be taken in the morning and evening. This will ensure good mood during the whole day. To put the nervous system in order, tea from these herbs is consumed for a month. Then the course is repeated periodically.

The following collection helps perfectly: meadowsweet, hop cones and mint. These herbs are dried, mixed and stored in a linen bag. If you have poor sleep, brew tea from this mixture and drink it in the evening before bed. If the taste seems too strong, add a little sugar or honey.

How to live if there was a myocardial infarction? Statistics on life expectancy after a heart attack. Permissible loads and lifestyle recommendations.

This article is intended for persons over 18 years of age

Have you already turned 18?

How long do they live after a heart attack?

Many reasons contribute to the “rejuvenation” of myocardial infarction:

• foods high in cholesterol;
• smoking;
• sedentary lifestyle;
• improper use or selection of hormonal contraceptives;
• stress in the workplace.

Important! Most birth control pills contain high concentrations of hormones that promote blood clotting. If a woman has a tendency to form blood clots, some pills are contraindicated for her. The selection of hormonal contraceptives should be carried out only by her gynecologist, carefully collecting anamnesis.

Survival statistics are divided into three time periods:

• first day;
• first month
• a year after the heart attack.

According to statistics, on average, every third of all patients dies within the first hour after an attack before receiving medical care.

During the first month, 15 to 25% of all patients who suffer myocardial damage die. Changes in the structure of the heart muscle create the conditions for new heart attacks. There is a high risk for a person not to survive a second heart attack.

About 10% of patients die within one year. If the patient's age exceeds 65 years, the mortality rate among such people reaches 35%.

Due to the shift in the age range of heart diseases, the prognosis, rehabilitation and prevention of heart diseases are becoming even more relevant. How many years a person lives depends on many factors:

• patient's age;

• timeliness of assistance provided, use of necessary medications;
• elapsed time since myocardial injury;
• the extent of myocardial damage.

At a younger age, patients can more easily tolerate any disease, including diseases of the cardiovascular system. If a patient is 45 years old, he has a greater chance of surviving a myocardial infarction for 5-10 years than, for example, a patient who suffered an attack at 80 years old. Younger people experience relative recovery faster.

The more time has passed since the onset of ischemic heart damage, the better the prognosis for life. As a rule, gradual adaptation of the heart muscle to scar changes occurs. This adaptation indicates the high potential of the body's reserve forces.

A heart attack causes necrosis of the muscular walls of the heart, which leads to changes:

• loss of contractile potential of the heart;
• conduction disturbance;
• the occurrence of arrhythmias.

For older people, the combination of chronic pathologies of other organs and a scar on the myocardium, conduction disturbances creates suitable conditions for repeated heart attacks, and increases the risk of sudden cardiac death. There are often situations when surgical intervention is indicated, for example, the installation of stents. If it is not followed, as a result, the person may die from repeated attacks.

The basis for success in the first hours of the onset of the disease is timely thrombolytic therapy. In the first month, there remains a possibility of developing a recurrent myocardial infarction. There is a risk of new blood clots breaking off against the background of a weakened myocardium. The formation of scar tissue lasts 1-2 months.

How long a person will live depends on the extent of the lesion. Transmural necrosis of the posterior or anterior wall of the left ventricular myocardium has a worse prognosis than small-focal necrosis. With small focal lesions, a smaller volume of cardiac tissue is affected. Accordingly, the damage heals easier and faster.

Life after a heart attack

How to continue to live with myocardial infarction? What will you have to give up? A person can do a lot himself to increase his chances of survival, regardless of age and in the absence of mental disorders. In addition to following all the doctor’s instructions and the rehabilitation course, you need to change your lifestyle.

A reminder on how to behave after myocardial infarction and stenting includes the following points:

1. Taking all medications prescribed by the cardiologist, performing surgical operations as indicated.
2. Exercise therapy course.
3. Physical activity.
4. Eliminating the source of stress.
5. Rejection of bad habits.
6. Diet.

Some medications prescribed by cardiologists must be taken for life. This is especially true for patients suffering from hypertension and atherosclerosis.

Important! Despite the relief that comes after taking the medications, you cannot stop them on your own.

Very often, patients who have suffered a heart attack have hypertension or coronary heart disease, problems with blood clotting. The following drugs are prohibited for use:

• capable of increasing blood pressure;
• vasoconstrictors;
• psychostimulants;
• promoting blood thickening.

Most of the drugs will not be prescribed by any doctor who knows about the history of heart disease. However, if you are a follower of traditional medicine and often like to experiment with herbs, you need to know dangerous plants. These include:

• nettle;
• yarrow;
• viburnum bark;
• arnica;
• Lagohillus intoxicating;
• guarana;
• ginseng;
• tea bush, lemongrass;
• oregano;
• immortelle.

The components of these herbs can increase blood clotting and increase blood pressure. They do not directly lead to the development of new heart damage, but create a very favorable background for more serious factors.

Particular attention must be paid to dental procedures. Before dental treatment, preparation is necessary. If the patient experiences stress when going to the dentist, it is necessary to take sedatives. It is better to prescribe the drug to a cardiologist together with a dentist. The medication should not harm the patient. Increased attention should be paid to the following dental procedures:

1. Anesthesia.
2. Tooth extraction.
3. Removing dental plaque.
4. Preparation of teeth for crowns.

Important! The dentist must know about pathologies of the cardiovascular system. Since anesthesia is often required, the doctor should choose an anesthetic with little or no epinephrine. Adrenaline constricts blood vessels, increases blood pressure, and can contribute to a hypertensive crisis.

You should not refuse pain relief. Painful shock can trigger a heart attack. Sometimes, when taking impressions for crowns, special threads soaked in adrenaline are used. The concentration of adrenaline on these threads may fluctuate. The dentist should choose a floss without impregnation.

What people with a stent and heart pathologies should not do:

• take part in competitive sports;
• intense cardio exercise without heart rate control (running, swimming);
• lift weights;
• perform endurance loads (long heavy hikes, performing exercises without a break);
• be in conditions of lack of oxygen;
• drinking alcohol;
• smoke.

Physical activity is allowed, but only if the load algorithm is developed by a specialist in exercise therapy. There are certain heart rate indicators that limit the intensity of exercise. For an elderly person, quiet, accompanied walks in the fresh air will be quite enough.

Since heart attacks occur in fairly young people, the question of intimate life after the disease surprises few people. Doctors note a pattern that women have more problems in the intimate sphere after heart disease. Nevertheless, sexual activity is possible, but there are nuances that should be explained by a cardiologist. General rules to renew intimate relationships:

1. Abstinence from sex for 30 days from the date of discharge from the hospital.
2. Mandatory monitoring of blood pressure and heart rate.
3. Intimate relationships can begin in a calm environment with minimal stress.

Important (especially for men)! Most patients experience a deterioration in the quality of their sexual life before or after a heart attack. Many men have no erection. There are many drugs that can normalize this function for a while. These medications have a side effect of increasing blood pressure. The drugs can only be used with the approval of a cardiologist.

A diet for pathologies of the heart and blood vessels excludes the following foods:

• pork;
• legumes;
• milk;

• meat and fish broths;
• flour products;
• marinades;
• smoked meats;
• salty cheeses.

Important! The emphasis in nutrition should be on food containing vegetable fats, low-fat meat, fish, and vegetables. Culinary processing involves steaming, baking, boiling without the use of spices and with a small amount of salt.

How to live after a massive heart attack

How long people live after a myocardial infarction depends solely on the type of heart attack, the extent and timeliness of assistance in the first hours. After scar formation, life expectancy is influenced more by the person himself. Small focal necrosis will have less serious consequences than an extensive infarction of the posterior or anterior myocardial wall, but without compliance with the cardiologist’s prescriptions, its prognosis is unfavorable. Reviews from a large number of people indicate an increase in the incidence of survival and an improvement in the quality of life of the majority of patients when all medical recommendations are followed.

To summarize, we can state that the following changes will occur in your life after a heart attack:

• leaving a job that involves heavy physical activity or stress, no matter how interesting or profitable it may be;
• a course of exercise therapy after discharge from the hospital;
• Lifelong use of blood pressure lowering drugs, statins.
• mandatory light physical exercise with heart rate control;
• restriction of activity. Some forms of active recreation are not available, sexual activity should be less intense;
• giving up alcohol and smoking;
• food restrictions.

Life must be changed completely. In addition to material costs, enormous willpower is also required. All activities cannot guarantee a successful outcome, but the chances will be significantly higher, as will the quality of life.

Modern protection of metals from corrosion is based on the following methods:

increasing the chemical resistance of structural materials,

insulation of the metal surface from an aggressive environment,

reducing the aggressiveness of the production environment,

reduction of corrosion by applying external current (electrochemical protection).

These methods can be divided into two groups. The first two methods are usually implemented before the start of production operation of the metal product (selection of structural materials and their combinations at the stage of design and manufacture of the product, application of protective coatings to it). The last two methods, on the contrary, can only be carried out during the operation of the metal product (passing current to achieve a protective potential, introducing special inhibitor additives into the process environment) and are not associated with any pre-treatment before use.

When using the first two methods, the composition of steels and the nature of the protective coatings of a given metal product cannot be changed during its continuous operation in conditions of changing aggressiveness of the environment. The second group of methods allows, if necessary, to create new protection modes that ensure the least corrosion of the product when their operating conditions change. For example, in different sections of the pipeline, depending on the aggressiveness of the soil, different cathode current densities can be maintained or different inhibitors can be used for different types of oil pumped through pipes of a given composition.

However, in each case it is necessary to decide which of the means or in what combination of them can obtain the greatest economic effect.

The following basic security solutions are widely used metal structures from corrosion:

1. Protective coatings

Metal coatings.

Based on the principle of protective action, anodic and cathodic coatings are distinguished. Anodic coatings have a more negative electrochemical potential in an aqueous solution of electrolytes than the protected metal, while cathodic coatings have a more positive one. Due to the potential shift, anodic coatings reduce or completely eliminate corrosion of the base metal in the pores of the coating, i.e. provide electrochemical protection, while cathodic coatings can increase corrosion of the base metal in the pores, but they are used because they increase the physical and mechanical properties of the metal, such as wear resistance and hardness. But this requires significantly greater thicknesses of coatings, and in some cases additional protection.

Metal coatings are also divided according to the method of their preparation (electrolytic deposition, chemical deposition, hot and cold application, thermal diffusion treatment, spray metallization, cladding).

Non-metallic coatings

These coatings are obtained by applying various non-metallic materials to the surface - paints, rubber, plastic, ceramic, etc.

The most widely used paint coatings, which can be divided according to purpose (weather-resistant, limited weather-resistant, water-resistant, special, oil-and-gasoline-resistant, chemical-resistant, heat-resistant, electrical insulating, conservation) and according to the composition of the film-forming agent (bitumen, epoxy, organosilicon, polyurethane, pentaphthalic, etc.). )

Coatings obtained by chemical and electrochemical surface treatment

These coatings are films of insoluble products formed as a result of the chemical interaction of metals with the external environment. Since many of them are porous, they are used primarily as sublayers for lubricants and paint coatings, increasing the protective ability of the coating on the metal and providing reliable adhesion. Application methods - oxidation, phosphating, passivation, anodizing.

2. Treatment of a corrosive environment in order to reduce corrosive activity.

Examples of such processing include: neutralization or deoxygenation corrosive environments, as well as the use of various types of corrosion inhibitors, which are introduced in small quantities into an aggressive environment and create an adsorption film on the metal surface, inhibiting electrode processes and changing the electrochemical parameters of metals.

3. Electrochemical protection of metals.

By cathodic or anodic polarization from an external current source or by attaching protectors to the protected structure, the metal potential shifts to values ​​at which corrosion is greatly slowed down or completely stopped.

• 4. Development and production of new metal structural materials with increased corrosion resistance by removing impurities from the metal or alloy that accelerate the corrosion process (removing iron from magnesium or aluminum alloys, sulfur from iron alloys, etc.), or introducing new components into the alloy, greatly increasing corrosion resistance (for example, chromium in iron, manganese in magnesium alloys, nickel in iron alloys, copper in nickel alloys, etc.).
• 5. Transition in a number of structures from metal to chemically resistant materials (plastic, high-polymer materials, glass, ceramics, etc.).
• 6. Rational design and operation of metal structures and parts (elimination of unfavorable metal contacts or their insulation, elimination of cracks and gaps in the structure, elimination of areas of stagnation of moisture, impact action of jets and sudden changes in flow rates in the structure, etc.).

Design issues anti-corrosion protection building structures are given serious attention both in our country and abroad. When choosing design solutions, Western companies carefully study the nature of aggressive influences, operating conditions of structures, and the moral service life of buildings, structures and equipment. In this case, the recommendations of companies that produce materials for anti-corrosion protection and have laboratories for research and processing of protective systems from the materials they produce are widely used.

The relevance of solving the problem of anti-corrosion protection is dictated by the need to preserve natural resources, protection environment. This problem is widely reflected in the press. Scientific works, prospectuses, catalogs are published, and international exhibitions for the purpose of exchanging experience between developed countries peace.

Thus, the need to study corrosion processes is one of the most important problems.

Surface cleaning and preparation

Ideal corrosion protection of 80% is ensured proper preparation surface, and only 20% by the quality of the paints and varnishes used and the method of their application.

1. Cleaning steel and removing rust

The duration and effectiveness of the coating on steel surfaces depends to a very large extent on how carefully the surface is prepared for painting.

Surface preparation consists of preliminary preparation aimed at removing scale, rust and foreign matter, if any, from the steel surface before applying a shop primer or primer.

Secondary surface preparation is aimed at removing rust or foreign matter, if present, from the steel surface with a factory primer or primer before applying the anti-corrosion paint system.

A steel surface can be cleaned of rust in the following ways:

Wire brush cleaning:

Wire brushing, usually carried out with rotating wire brushes, is a common method not suitable for descaling but suitable for preparation welds. The main disadvantage is that the treated surface is not completely freed from corrosion products and begins to shine and become greasy. This reduces the adhesion of primers and the effectiveness of the paint system.

Stumping:

Chipping or mechanical chipping is usually carried out in combination with wire brushing. This is sometimes suitable for local repairs when using conventional or special paint systems. This is not suitable for general training surfaces for painting with epoxy and chlorinated rubber paints. Chipping can be used to remove thick layers of rust and provides savings in subsequent sandblasting.

Pneumatic Hammer:

Remove rust, paint, etc. from corners and protrusions to achieve a clean, rough surface.

Thermal method:

Flame surface cleaning involves removing rust by heat treatment when using special equipment (acetylene or propane with oxygen). This removes almost all the scale, but less so the rust. Therefore, this method cannot meet the requirements of modern painting systems.

Grinding:

Grinding involves the use of rotating wheels coated with abrasive material. It is used for minor repairs or to remove small foreign particles. The quality of these grinding wheels has been improved to a great extent and it can provide a good standard of surface preparation.

Mechanical cleaning:

A method of manual surface cleaning during which a primed and painted surface is roughened and any visible contamination is removed (with the exception of oil stains and traces of rust).

easy cleaning, purpose: roughening the new surface

Abrasive: fine (0.2-0.5mm)

heavy cleaning (ISO Sa1), purpose: removal of layers of old coating

Abrasive: fine to medium (0.2-0.5/0.2-1.5mm)

Sandblasting:

The collision of a stream of abrasive material with high kinetic energy with a prepared surface. This process is controlled either manually with a jet or automatically with a wheel and paddles, and is the most thorough method of rust removal. Sandblasting using centrifuge, compressed air and vacuum are well known types.

The particles are only substantially spherical and solid and must contain a minimum amount of foreign matter and irregularly shaped particles.

Primers used after shot blasting must be tested for their performance.

Coarse abrasive

The particles must have an angular shape with sharp cutting edges, and the “halves” must be removed. Unless otherwise stated in the specification, sand of mineral origin should be used.

Wet (abrasive) (sandblasting) cleaning:

Very high pressure wet cleaning

Pressure = over 2000 bar

cleaning speed = max. 10-12 m2/hour depending on the material to be removed.

Usage: complete removal of all coatings and rust. The result is comparable to dry sandblasting, but with flare-ups of rust after drying.

High pressure wet cleaning

Pressure = up to 1300 bar

Cleaning speed = max. 5 m2/hour depending on the material to be removed. Using much less pressure, this method is used to remove contaminants from any substrate.

Use: removal of salt and other contaminants, coatings and rust.

Wet abrasive low pressure sandblasting

Pressure= 6-8 kg/cm2

Cleaning speed = 10-16 m2/hour depending on the material to be removed.

Uses: reducing abrasiveness, reducing dust, removing salt, eliminating the risk of sparks. The result is comparable to dry sandblasting, but with flare-ups of rust after drying.

Steam cleaning: Pressure=100-120 kg/cm2

Use: Removal of water-soluble and emulsified contaminants: the substrate dries faster than when treating the substrate with water.

ISO standards:

When determining the exact degree of rust removal and cleaning of a steel surface before painting, use International standard ISO 8501-01-1988 and ISO 8504-1992.

ISO 8501-01 is used for scale. This means the following levels of rust infestation:

A - the steel surface is largely covered with scale, but to a small extent or not at all affected by rust.

B - a steel surface that has begun to rust and from which scale has begun to crumble.

C - steel surface from which scale has fallen off and can be removed, but with slight visible pitting.

D - steel surface from which scale has fallen off, but with slight pitting visible to the naked eye.

Degrees of surface preparation The ISO standard specifies seven grades of surface preparation.

The following standards are often used in specifications:

ISO-St Processing by hand and power tools.

Surface preparation manually and using power tools: scraping, wire brushing, mechanical brushing and grinding - is indicated by the letters "St".

Before cleaning by hand or power tools begins, thick layers of rust must be removed by chipping. Visible contamination from oil, grease and dirt must also be removed.

After cleaning by hand and power tools, the surface should be free of loose paint and dust.

ISO-St2 Thorough cleaning by hand and power tools

When viewed superficially with the naked eye, the substrate should appear free of visible traces of oil, grease and dirt and free of loose scale, rust, paint and foreign matter.

ISO-St3 Very thorough cleaning by hand and power tools

Same as for St2, but the substrate must be cleaned much more thoroughly until a metallic sheen appears.

ISO-Sa sandblasting

Surface preparation by sandblasting is indicated by the letters "Sa".

Before sandblasting can begin, thick layers of rust must be removed by chipping. Visible oil, grease and dirt must also be removed.

After sandblasting, the substrate must be cleaned of dust and debris.

ISO-Sa1 light sandblasting

When inspected with the naked eye, the surface should appear free of visible oil, grease and dirt stains and free of loose scale, rust, paint and other foreign matter.

ISO-Sa2 Thorough sandblasting

When inspected with the naked eye, the surface should appear free of visible oil, grease and dirt and free of most scale, rust, paint and other foreign matter. Any residual contamination must have a tight seal.

ISO-Sa2.5 Very thorough sandblasting

When inspected with the naked eye, the surface should appear free of visible oil, grease and dirt and free of most scale, rust, paint and other foreign matter. Any residual traces of infection should appear only in the form of barely noticeable spots and streaks.

ISO-Sa3 Sandblasting to visually clean steel.

When inspected with the naked eye, the surface should appear free of visible oil, grease and dirt and free of most scale, rust, paint and other foreign matter. The surface should have a uniform metallic luster.

Surface roughness after sandblasting:

To determine roughness, various notations are used, such as Rz, Rt Ra.

Rz - average elevation compared to the level of the plain = profile of abrasive material

Rt - maximum elevation relative to the level of the plain

Ra is the average distance to an imaginary center line that can be drawn between peaks and plains (ISO3274).

Abrasive profile (Rz) - 4 to 6 times C.L.A. (Ra)

Direct measurement of T.S.S. primers applied to sandblasted steel up to a thickness of 30 microns are very inaccurate. A primer with a dry layer thickness of 30 microns or more forms an average thickness, and not a thickness at the tops.

When the specifications mention abrasive profile Rz, sandblasting to ISO - Sa2.5 standard should be achieved using mineral sand unless nothing else is mentioned.

Above Ra at 17 µm (abrasive material profile R at T.C.S. 100 µm) it is recommended to use an additional layer of primer to cover the roughness.

If heavily rusted steel is sandblasted, a profile in excess of 100 microns is often achieved.

Metals have been used by humans since prehistoric times, and products made from them are widespread in our lives. The most common metal is iron and its alloys. Unfortunately, they are susceptible to corrosion, or rusting - destruction as a result of oxidation. Timely protection against corrosion allows you to extend the service life of metal products and structures.

Types of corrosion

Scientists have been fighting corrosion for a long time and have identified several main types:

• Atmospheric. Oxidation occurs due to contact with air oxygen and water vapor contained in it. The presence of pollutants in the air in the form of chemically active substances accelerates rusting.
• Liquid. It takes place in an aquatic environment; salts contained in water, especially sea water, accelerate oxidation many times over.
• Soil. Products and structures located in the ground are susceptible to this type. Chemical composition soil, groundwater and leakage currents create a special environment for the development of chemical processes.

Based on the environment in which the product will be used, suitable methods of corrosion protection are selected.

Typical types of rust damage

The following characteristic types of corrosion damage are distinguished:

• The surface is covered with a continuous rusty layer or individual pieces.
• The part has small areas of rust penetrating into the thickness of the part.
• In the form of deep cracks.
• One of the components in the alloy is oxidized.
• Deep penetration throughout the entire volume.
• Combined.

Due to their occurrence they are also divided into:

• Chemical. Chemical reactions with active substances.
• Electrochemical. Upon contact with electrolytic solutions, an electric current arises, under the influence of which the electrons of the metals are replaced, and the crystalline structure is destroyed with the formation of rust.

Metal corrosion and methods of protection against it

Scientists and engineers have developed many ways to protect metal structures from corrosion.

Corrosion protection of industrial and building structures, various types transport is carried out by industrial means.

They are often quite complex and expensive. To protect metal products in households, household methods are used that are more affordable and do not involve complex technologies.

Industrial

Industrial methods of protecting metal products are divided into a number of areas:

• Passivation. When smelting steel, alloying additives such as Cr, Mo, Nb, Ni are added to its composition. They contribute to the formation of a durable and chemically resistant film of oxides on the surface of the part, preventing the access of aggressive gases and liquids to the iron.
• Protective metal coating. A thin layer of another metal element is applied to the surface of the product - Zn, Al, Co, etc. This layer protects the iron from rusting.
• Electrical protection. Plates made of another metal element or alloy, so-called anodes, are placed next to the part to be protected. Currents in the electrolyte flow through these plates, not through the part. This is how they protect underwater parts of marine transport and drilling platforms.
• Inhibitors. Special substances that slow down or completely stop chemical reactions.
• Protective paint coating.
• Heat treatment.

The corrosion protection methods used in the industry are very diverse. The choice of a specific corrosion control method depends on the operating conditions of the protected structure.

Household

Household methods of protecting metals from corrosion usually come down to applying protective paint and varnish coatings. Their composition can be very diverse, including:

• silicone resins;
• polymer materials;
• inhibitors;
• small metal filings.

A separate group includes rust converters - compounds that are applied to structures already affected by corrosion. They restore iron from oxides and prevent re-corrosion. Converters are divided into the following types:

• Soils. They are applied to a cleaned surface and have high adhesion. They contain inhibitory substances, allowing you to save finishing paint.
• Stabilizers. Convert iron oxides into other substances.
• Converters of iron oxides to salts.
• Oils and resins that envelop rust particles and neutralize it.

When choosing primer and paint, it is better to take them from the same manufacturer. This way you will avoid problems with compatibility of paints and varnishes.

Protective paints for metal

According to the operating temperature conditions, paints are divided into two large groups:

• conventional, used at temperatures up to 80 °C;
• heat resistant.

Based on the type of binder base, the paints are:

• alkyd;
• acrylic;
• epoxy.

Paint and varnish coatings for metal have the following advantages:

• high-quality surface protection against corrosion;
• ease of application;
• quick drying;
• many different colors;
• long service life.

Hammer enamels are very popular, not only protecting the metal, but also creating an aesthetic appearance. Silver paint is also common for metal processing. Aluminum powder is added to its composition. Metal protection occurs due to the formation of a thin film of aluminum oxide.

Two-component epoxy mixtures have exceptional coating strength and are used for components subject to high loads.

Metal protection at home

To reliably protect hardware from corrosion, the following sequence of actions should be performed:

• clean the surface of rust and old paint using a wire brush or abrasive paper;
• degrease the surface;
• immediately apply a layer of primer;
• After the primer has dried, apply two layers of base paint.

When working, you should use personal protective equipment:

• gloves;
• respirator;
• glasses or a transparent shield.

Methods for protecting metals from corrosion are constantly being improved by scientists and engineers.

Methods of resisting corrosion processes

The main methods used to counteract corrosion are given below:

• increasing the ability of materials to resist oxidation by changing its chemical composition;
• insulation of the protected surface from contact with active media;
• reducing the activity of the environment surrounding the product;
• electrochemical.

The first two groups of methods are used during the manufacture of the structure, and the second - during operation.

Methods for increasing resistance

Elements are added to the alloy to increase its corrosion resistance. Such steels are called stainless steels. They do not require additional coatings and are aesthetically pleasing. appearance. Nickel, chromium, copper, manganese, and cobalt are used as additives in certain proportions.

The resistance of materials to rust is also increased by removing corrosion-accelerating components from their composition, such as oxygen and sulfur from steel alloys, and iron from magnesium and aluminum.

Reduction of environmental aggressiveness and electrochemical protection

In order to suppress oxidation processes in external environment special compounds called inhibitors are added. They slow down chemical reactions tens and hundreds of times.

Electrochemical methods come down to changing the electrochemical potential of a material by passing electric current. As a result, corrosion processes slow down greatly or even stop altogether.

Film protection

The protective film prevents the access of active substance molecules to metal molecules and thus prevents corrosion phenomena.

Films are formed from paints, plastics and resins. Paint coatings are inexpensive and easy to apply. They cover the product in several layers. A layer of primer is applied under the paint, which improves adhesion to the surface and allows you to save on more expensive paint. Such coatings last from 5 to 10 years. A mixture of manganese and iron phosphates is sometimes used as a primer.

Protective coatings are also created from thin layers of other metals: zinc, chromium, nickel. They are applied by galvanic method.

Coating with a metal with a higher electrochemical potential than the base material is called anodic. It continues to protect the base material, distracting active oxidizing agents, even in the event of partial destruction. Coatings with a lower potential are called cathodic. If such a coating is damaged, it accelerates corrosion through electrochemical processes.

The metal coating can also be applied by spraying in a plasma jet.

Joint rolling of sheets of base and protecting metal heated to the plasticity temperature is also used. Under pressure, mutual diffusion of molecules of elements occurs into each other’s crystal lattices and the formation of a bimetallic material. This method is called cladding.