What is the process of induction
Induced labour | Pregnancy Birth and Baby
What is an induced labour?
Labour normally starts naturally any time between 37 and 42 weeks of pregnancy. The cervix softens and starts to open, you will get contractions, and your waters break.
In an induced labour, or induction, these labour processes are started artificially. It might involve mechanically opening your cervix, breaking your waters, or using medicine to start off your contractions — or a combination of these methods.
In Australia, about 1 in 3 women has an induced labour.
What are the differences between an induced and a natural labour?
An induced labour can be more painful than a natural labour. In natural labour, the contractions build up slowly, but in induced labour they can start more quickly and be stronger. Because the labour can be more painful, you are more likely to want some type of pain relief.
If your labour is induced, you are also more likely to need other interventions, such as the use of forceps or ventouse (vacuum) to assist with the birth of your baby. You will not be able to move around as much because the baby will be monitored more closely than during a natural labour.
You will only be offered induced labour if there is a risk to you or your baby's health. Your doctor might recommend induced labour if:
- you are overdue (more than 41 weeks pregnant)
- there is a concern the placenta is not working as it should
- you have a health condition, such as diabetes, kidney problems, high blood pressure or pre-eclampsia
- the baby is making fewer movements, showing changes in its heart rate, or not growing well
- your waters have broken, but the contractions have not started naturally
- you are giving birth to more than one baby (twins or multiple birth)
Not everyone can have an induced labour. It is not usually an option if you have had a caesarean section or major abdominal surgery before, if you have placenta praevia, or if your baby is breech or lying sideways.
Can I decide whether to have an induced labour?
If you are overdue, you might decide to wait and see if labour will start naturally.
However, if there is a chance you or your baby are at risk of complications, you might need to consider induced labour before your due date.
When making your decision, discuss the risks and benefits with your doctor. Do not be afraid to ask lots of questions, such as:
- Why do I need an induction?
- How will it affect me and my baby?
- What will happen if I do not have the induction?
- What procedures are involved and how will you care for me and my baby?
You might need to consider several other health concerns. For example, there is a higher risk of stillbirth or other problems if your baby is not born before 42 weeks, and an increased risk of infection if your waters break more than 24 hours before labour starts.
What can I expect with an induced labour?
During the late stages of your pregnancy, your healthcare team will carry out regular checks on your health and your baby's heath. These checks help them decide whether it is better to induce labour or to keep the baby inside.
Always tell your doctor or midwife if you notice your baby is moving less than normal.
If they decide it is medically necessary to induce labour, first your doctor or midwife will do an internal examination by feeling inside your vagina. They will feel your cervix to see if it is ready for labour. This examination will also help them decide on the best method for you.
It can take from a few hours to as long as 2 to 3 days to induce labour. It depends how your body responds to the treatment. It is likely to take longer if this is your first pregnancy or you are less than 37 weeks pregnant.
What options are there to induce labour?
There are different ways to induce labour. Your doctor or midwife will recommend the best method for you when they examine your cervix. You may need a combination of different strategies. You will need to provide written consent for the procedure.
Sweeping the membranes
During a vaginal examination, the midwife or doctor makes circular movements around your cervix with their finger.
This action should release a hormone called prostaglandins. You do not need to be admitted to hospital for this procedure and it is often done in the doctor's room. This can be enough to get labour started, meaning you will not need any other methods.
Risks: This is a simple and easy procedure; however, it does not always work. It can be a bit uncomfortable, but it does not hurt.
Oxytocin
A synthetic version of the hormone oxytocin is given to you via a drip in your arm to start your contractions. When the contractions start, the amount of oxytocin is adjusted so you keep on having regular contractions until the baby is born. This whole process can take several hours.
Risks: Oxytocin can make contractions stronger, more frequent and more painful than in natural labour, so you are more likely to need pain relief. You will not be able to move around much because of the drip in your arm and you will also have a fetal monitor around your abdomen to monitor your baby.
Sometimes the contractions can come too quickly, which can affect the baby's heart rate. This can be controlled by slowing down the drip or giving you another medicine.
Artificial rupture of membranes ('breaking your waters')
Artificial rupture of membranes (ARM) is used when your waters do not break naturally. Your doctor or midwife inserts a small hook-like instrument through your vagina to make a hole in the membrane sac that is holding the amniotic fluid. This will increase the pressure of your baby's head on your cervix, which may be enough to get labour started. Many women will also need oxytocin to start their contractions.
Risks: ARM can be a bit uncomfortable but not painful. There is a small increased risk of a prolapsed umbilical cord, bleeding or infection.
Prostaglandins
A synthetic version of the hormone prostaglandins is inserted into your vagina to soften your cervix and prepare your body for labour. It can be in the form of a gel, which may be given in several doses (usually every 6 to 8 hours), or a pessary and tape (similar to a tampon), which slowly releases the hormone over 12 to 24 hours.
You will need to lie down and stay in hospital after the prostaglandins is inserted. You may also then need ARM if your waters have not broken, or oxytocin to bring on the contractions.
Prostaglandins gel is often the preferred method of inducing labour since it is the closest to natural labour. Tell your midwife or doctor straight away if you start to experience painful, regular contractions 5 minutes apart for your first baby, or 10 minutes apart for subsequent babies, or if your waters break, because these are both signs that your labour is beginning.
Risks: Some women find their vagina is sore after the prostaglandin gel, or they might experience nausea, vomiting or diarrhoea. These side effects are rare and there is no evidence that induction using prostaglandin is any more painful than a natural labour.
Very rarely, the contractions can come too strongly, which can affect the baby's heart rate. This can be controlled by giving you another medicine or removing the pessary.
You need to let your doctor or midwife know immediately if you start bleeding, or if your baby is moving less, because this could be a sign that something is wrong.
Cervical ripening balloon catheter
A cervical ripening balloon catheter is a small tube attached to a balloon that is inserted into your cervix. The balloon is inflated with saline, which usually puts enough pressure on your cervix for it to open. It stays in place for up to 15 hours, and then you will be examined again.
Tell your midwife or doctor straight away if you start to experience painful, regular contractions 5 minutes apart for your first baby, or 10 minutes apart for subsequent babies, or if your waters break, because these are both signs that your labour is beginning.
You may also need ARM or oxytocin if you are using a cervical ripening balloon catheter.
Risks: Inserting the catheter can be a bit uncomfortable but not painful.
You also need to let your doctor or midwife know immediately if you start bleeding, or your baby is moving less, because this could be a sign that something is wrong.
Can I have pain relief during induced labour?
Induced labour is usually more painful than natural labour. Depending on the type of induction you are having, this could range from discomfort with the procedure or more intense and longer lasting contractions as a result of the medication you have been given. Women who have induced labour are more likely to ask for an epidural for relief.
Because inductions are almost always done in hospital, the full range of pain relief should be available to you. There is usually no restriction on the type of pain relief you can have if your labour is induced.
Are there any risks with inducing labour?
There are some increased risks if you have an induced labour. These include that:
- it will not work — in about 1 of 4 cases, women go on to have a caesarean
- your baby will not get enough oxygen and their heart rate is affected
- you or your baby get an infection
- your uterus tears
- you bleed a lot after the birth
What happens if the induction does not work?
Not all induction methods will work for everyone.
Your doctor may try another method, or you might need to have a caesarean. Your doctor will discuss all of these options with you.
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Labor induction - Mayo Clinic
Overview
Labor induction — also known as inducing labor — is prompting the uterus to contract during pregnancy before labor begins on its own for a vaginal birth.
A health care provider might recommend inducing labor for various reasons, primarily when there's concern for the mother's or baby's health. An important factor in predicting whether an induction will succeed is how soft and expanded the cervix is (cervical ripening). The gestational age of the baby as confirmed by early, regular ultrasounds also is important.
If a health care provider recommends labor induction, it's typically because the benefits outweigh the risks. If you're pregnant, understanding why and how labor induction is done can help you prepare.
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Why it's done
To determine if labor induction is necessary, a health care provider will likely evaluate several factors. These include the mother's health and the status of the cervix. They also include the baby's health, gestational age, weight, size and position in the uterus. Reasons to induce labor include:
- Nearing 1 to 2 weeks beyond the due date without labor starting (postterm pregnancy).
- When labor doesn't begin after the water breaks (prelabor rupture of membranes).
- An infection in the uterus (chorioamnionitis).
- When the baby's estimated weight is less than the 10th percentile for gestational age (fetal growth restriction).
- When there's not enough amniotic fluid surrounding the baby (oligohydramnios).
- Possibly when diabetes develops during pregnancy (gestational diabetes), or diabetes exists before pregnancy.
- Developing high blood pressure in combination with signs of damage to another organ system (preeclampsia) during pregnancy. Or having high blood pressure before pregnancy, developing it before 20 weeks of pregnancy (chronic high blood pressure) or developing the condition after 20 weeks of pregnancy (gestational hypertension).
- When the placenta peels away from the inner wall of the uterus before delivery — either partially or completely (placental abruption).
- Having certain medical conditions. These include heart, lung or kidney disease and obesity.
Elective labor induction is the starting of labor for convenience when there's no medical need. It can be useful for women who live far from the hospital or birthing center or who have a history of fast deliveries.
A scheduled induction might help avoid delivery without help.
In such cases, a health care provider will confirm that the baby's gestational age is at least 39 weeks or older before induction to reduce the risk of health problems for the baby.
As a result of recent studies, women with low-risk pregnancies are being offered labor induction at 39 to 40 weeks. Research shows that inducing labor at this time reduces several risks, including having a stillbirth, having a large baby and developing high blood pressure as the pregnancy goes on. It's important that women and their providers share in decisions to induce labor at 39 to 40 weeks.
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Risks
Uterine incisions used during C-sections
Uterine incisions used during C-sections
A C-section includes an abdominal incision and a uterine incision. After the abdominal incision, the health care provider will make an incision in the uterus. Low transverse incisions are the most common (top left).
Labor induction carries various risks, including:
- Failed induction.
An induction might be considered failed if the methods used don't result in a vaginal delivery after 24 or more hours. In such cases, a C-section might be necessary. - Low fetal heart rate. The medications used to induce labor — oxytocin or a prostaglandin — might cause the uterus to contract too much, which can lessen the baby's oxygen supply and lower the baby's heart rate.
- Infection. Some methods of labor induction, such as rupturing the membranes, might increase the risk of infection for both mother and baby. The longer the time between membrane rupture and labor, the higher the risk of an infection.
-
Uterine rupture. This is a rare but serious complication in which the uterus tears along the scar line from a prior C-section or major uterine surgery. Rarely, uterine rupture can also occur in women who have not had previous uterine surgery.
An emergency C-section is needed to prevent life-threatening complications.
The uterus might need to be removed. - Bleeding after delivery. Labor induction increases the risk that the uterine muscles won't properly contract after giving birth, which can lead to serious bleeding after delivery.
Labor induction isn't for everyone. It might not be an option if:
- You've had a C-section with a classical incision or major uterine surgery
- The placenta is blocking the cervix (placenta previa)
- Your baby is lying buttocks first (breech) or sideways (transverse lie)
- You have an active genital herpes infection
- The umbilical cord slips into the vagina before delivery (umbilical cord prolapse)
If you have had a C-section and have labor induced, your health care provider is likely to avoid certain medications to reduce the risk of uterine rupture.
How you prepare
Labor induction is typically done in a hospital or birthing center. That's because mother and baby can be monitored there, and labor and delivery services are readily available.
What you can expect
During the procedure
There are various ways of inducing labor. Depending on the circumstances, the health care provider might use one of the following ways or a combination of them. The provider might:
-
Ripen the cervix. Sometimes prostaglandins, versions of chemicals the body naturally produces, are placed inside the vagina or taken by mouth to thin or soften (ripen) the cervix. After prostaglandin use, the contractions and the baby's heart rate are monitored.
In other cases, a small tube (catheter) with an inflatable balloon on the end is inserted into the cervix. Filling the balloon with saline and resting it against the inside of the cervix helps ripen the cervix.
- Sweep the membranes of the amniotic sac. With this technique, also known as stripping the membranes, the health care provider sweeps a gloved finger over the covering of the amniotic sac near the fetus.
This separates the sac from the cervix and the lower uterine wall, which might help start labor. -
Rupture the amniotic sac. With this technique, also known as an amniotomy, the health care provider makes a small opening in the amniotic sac. The hole causes the water to break, which might help labor go forward.
An amniotomy is done only if the cervix is partially dilated and thinned, and the baby's head is deep in the pelvis. The baby's heart rate is monitored before and after the procedure.
- Inject a medication into a vein. In the hospital, a health care provider might inject a version of oxytocin (Pitocin) — a hormone that causes the uterus to contract — into a vein. Oxytocin is more effective at speeding up labor that has already begun than it is as at cervical ripening. The provider monitors contractions and the baby's heart rate.
How long it takes for labor to start depends on how ripe the cervix is when the induction starts, the induction techniques used and how the body responds to them.
It can take minutes to hours.
After the procedure
In most cases, labor induction leads to a vaginal birth. A failed induction, one in which the procedure doesn't lead to a vaginal birth, might require another induction or a C-section.
By Mayo Clinic Staff
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| Induction is a cognitive procedure by means of which a statement generalizing them is deduced from a comparison of the facts at hand. In scientific search (see Methods of scientific knowledge) induction involves the movement of knowledge from single statements about individual facts to statements of a more general nature. In logic (see Logic), the term "induction" is used as a synonym for the more precise, but more cumbersome, term "inductive reasoning" and is understood in a narrower sense: as a conclusion in which a general conclusion is built on the basis of particular premises. The most widely used kind of inductive reasoning is enumerative reasoning, i.e. reasoning containing a transition from premises stating that all known objects from a certain collection A have the property P and unknown - objects from A have P . Another type of inductive reasoning that is widely used is reasoning that contains a transition from premises stating that some object A had the property P at every point in time before the present, to the conclusion that A will have P at the future. Induction is widely used in all areas of scientific knowledge, playing an important role in the construction of empirical knowledge and the transition from empirical to theoretical knowledge. Inductive reasoning distinguishes complete and incomplete induction:
These varieties of incomplete induction play an extremely important role in scientific knowledge. Incomplete induction allows you to reduce the scientific search and come to general provisions, the disclosure of patterns, without waiting until all the phenomena of this class are studied in detail. However, it also includes a significant limitation, which consists in the fact that the conclusion of incomplete induction most often does not provide reliable knowledge. Since induction is closely connected with the development of experimental knowledge, it began to be used already in ancient times, although theoretically its simplest forms began to be analyzed only in ancient philosophy, in particular by Socrates, who introduced the concept of inductive reasoning, and Aristotle, who considered them as auxiliary means of justification sendings syllogisms (see Syllogism). In Aristotle, the understanding of induction is associated with the generalization of observations and means, in essence, a method of inference through which the ascent from the particular to the general is made. This Aristotelian view was adopted by the philosophers of the Epicurean school, who defended induction against the Stoics as the only authoritative method of proving the laws of nature. nine0016 Further development of the theory of induction is noted only in modern times, when the active growth of science, due to the accumulation, generalization and systematization of extensive empirical material, raised the question of studying the methods of scientific discovery, and the types of inductive reasoning themselves began to be studied for their reliability. From a philosophical point of view, the most interesting problem is the justification of induction - finding a rational basis for recognizing the legitimacy of inductive reasoning. The importance of the problem is due to the importance of inductive reasoning for modern science. Its successful solution involves finding an answer to the question on what basis we recognize some of the inductive reasoning as acceptable, despite the fact that in any inductive reasoning the truth of the premises does not guarantee the truth of the conclusion. All answers proposed since D. Hume, who raised this question, have been unsuccessful - every attempt to justify induction offered up to the present moment implicitly assumed the legitimacy of induction. At present, the consideration of the problem of induction, proposed by P. Strawson, who claims that the project of substantiating induction is self-contradictory, enjoys a certain popularity. According to Strawson, justifying induction is tantamount to giving inductive reasoning the status of deductive reasoning. | |
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At the same time, sendings can confirm or imply truth, but do not guarantee its receipt. This is where induction fundamentally differs from deduction (see Deduction), by means of which true conclusions are always obtained from true premises, subject to the rules of logical inference. 
In science, the basis of induction is experience, experiment and observation, during which individual facts are collected. Then, studying these facts, analyzing them, the researcher establishes common and recurring features of a number of phenomena included in a certain class. On this basis, he builds an inductive conclusion, the premises of which are judgments about single objects and phenomena with an indication of their recurring feature, and a judgment about a class that includes these objects and phenomena. As a conclusion, a judgment is obtained in which the attribute identified in a set of single objects is attributed to the entire class. The value of inductive inferences lies in the fact that they provide a transition from single facts to general provisions, allow you to detect dependencies between phenomena, build empirically based hypotheses, and come to generalizations. nine0016 
The conclusions of complete induction are deductive in the sense that the conclusion in them follows from the premises with logical necessity: if the premises are true, applying the known rules of logic, we cannot obtain a false conclusion. Full induction is applicable in cases where the class of objects under study is observable and all objects of this class can be enumerated. Thus, it implies the study of each of the objects included in the class, and on this basis, finding their common characteristics. However, in some cases there is simply no need to consider absolutely all objects of a particular class, in other cases it is impossible to do this due to the immensity of the class of phenomena being studied or due to the limitations of human practice. In such situations, incomplete induction is used. nine0053 
Thus, it implies the study of a limited number of objects of any particular class, since, as a rule, the number of all cases is practically incomprehensible, and a theoretical proof for an infinite number of these cases is impossible. Incomplete induction is no longer a logically justified reasoning, since from the point of view of logic only such conclusions are valid, for which no new information is required, except for that contained in the premises, but the conclusion of incomplete induction always says more than its premises can say . This, in fact, is the cognitive meaning of induction - the abstract work of thought helps to obtain new knowledge with a lack of existing [practical] knowledge. Incompleteness of induction can be determined not only by the number of premises (incompleteness with respect to the number of premises), but also by their nature (incompleteness with respect to the nature of premises). nine0005 There are two varieties of incomplete induction: popular induction (or enumeration induction) and scientific induction : 
The fixation of a new feature in a number of objects occurs here, as a rule, without a preliminary research plan: having found a similar feature in the first objects of a certain class that have come across and not having encountered a single contradictory case, they transfer the indicated feature to the entire class of objects. The absence of a contradictory case is the main reason for accepting an inductive inference. The discovery of such a case refutes the inductive generalization. The conclusion obtained by induction through a simple enumeration has a relatively low degree of certainty, and with continued research based on expanding the class of cases studied, it can often turn out to be erroneous. Therefore, popular induction can be used in scientific research when putting forward first and approximate hypotheses. It is often resorted to at the first stages of acquaintance with a new class of objects, but in general it cannot serve as a reliable basis for inductive generalizations obtained by science.
Such generalizations are built mainly on the basis of scientific induction. nine0053 
To a lesser extent, this applies to scientific induction, some varieties of which give reliable conclusions, but entirely to popular induction. Knowledge obtained in the framework of incomplete induction is usually problematic, probabilistic. This gives rise to the possibility of numerous errors, which are the result of hasty generalizations. This kind of generalization is especially characteristic of the early stages of scientific research. The problematic nature of most inductive conclusions requires their repeated verification by practice, comparison with the experience of the consequences derived from the inductive generalization. As these consequences coincide with the result of the experiment, the degree of reliability of the inductive conclusion increases. In this process, the justification of knowledge obtained by induction necessarily implies a movement from inductive generalizations to one or another particular case. Such a conclusion is already a deductive reasoning. Thus, induction is supplemented by deduction, which ensures the transition from probabilistic to reliable knowledge.
nine0016 
Of great importance in this regard were the works of F. Bacon, who began a systematic study of inductive procedures, considering them as the only scientific way of knowing and contrasting induction with speculative reasoning. Since the methods of Aristotelian syllogistic and induction through a simple enumeration of confirming cases could not be used to analyze empirical generalizations, Bacon, in contrast to Aristotle's Organon, creates his New Organon (1620), in which he sets out the "canons of induction" as methods for discovering new truths in science. Later, the theory of induction was developed in the works of J. St. Mill, who proposed five methods of inductive reasoning (Bacon-Mill canons of induction), through which conclusions are drawn about causal relationships between phenomena: the method of similarity; difference method; combined method of similarity and difference; residual method; concomitant change method. These inductive methods are known examples of plausible reasoning (see Reasoning plausible).
Subsequently, they received a number of refinements in the works of other researchers. However, with the help of the "canons of induction" it was possible to make only relatively simple empirical generalizations and establish logical relationships between the observed properties of phenomena. When science began to explore deeper laws that reveal the essence and internal mechanisms of phenomena, it became obvious that empirical methods based on induction are not able to do this, if only because it requires an appeal to abstract, theoretical concepts. In this regard, the view of induction changed radically, and instead of the logic of discovery, it began to be considered as a method of testing and substantiating hypotheses. Within of the hypothetical-deductive method (see Hypothetical-deductive method), it is the empirically verifiable consequences of a hypothesis that can be tested and confirmed with the help of inductively established facts. This view of induction found its most striking expression in the neo-positivist concept, in which the context of justification is sharply opposed to the context of discovery.
The task of the logic and philosophy of science is reduced solely to the substantiation of new knowledge, while the process of discovery is entirely related to the psychology of scientific creativity. Since the conclusion of induction does not logically follow from the premises, only a probabilistic relationship can be established between them, which is defined as the semantic degree of confirmation of the conclusion by its premises. Hence, the task of induction is not to invent rules for the discovery of new scientific truths, but to search for objective criteria for confirming hypotheses by their empirical premises, and if possible, then determining the quantitative degree of confirmation. From this point of view, other non-deductive reasoning (analogy, statistical inference) can also be attributed to induction in the sense that their conclusions are only probabilistic in nature and can be analyzed within the framework of a broader probabilistic logic. However, this leaves behind the heuristic function of induction, which is widely used to obtain generalizations from facts.
nine0016 
At the same time, the main value of inductive reasoning is that - unlike deductively correct reasoning - they allow us to receive new information; thus, justifying induction is tantamount to saying that inductive reasoning, contrary to evidence, does not lead to new information, which, according to Strawson, is absurd. In recent years, attempts have been made to supplement the induction with some premises or permissive procedures that provide more reliable conclusions in specific areas of research. In the same direction, an analysis of reproductive reasoning is carried out, where the search goes not from hypotheses to consequences, but, on the contrary, from consequences to hypotheses. Such techniques reduce the risk of error during induction, but in principle, induction - excluding the full and mathematical - always remains a probabilistic inference. In modern logic and philosophy of science, interest in the theory of induction is supported by applied research. nine0016 
Analysts first and second. - M., 1952. 
- "Questions of Philosophy", 1968, No. 9. 
- Ivanovo, 1956. 
— Amsterdam, 1986. What is induction? - Inductotherm Group Russia
The Inductotherm Group uses electromagnetic induction for melting, heating and welding in various applications and industries.
But what is induction? And how is it different from other heating methods?
Watching a piece of metal in an inductor turn red in a matter of seconds may surprise those unfamiliar with induction melting. nine0005 For an engineer, induction is a great heating method. Watching a piece of metal in an inductor turn red in a matter of seconds can be surprising to those unfamiliar with induction heating. Induction heating equipment requires an understanding of physics, electromagnetism, power electronics and process control, but the basic concepts behind induction heating are fairly easy to understand.Basics
Discovered by Michael Faraday, induction originates from a coil of conductive material (eg copper).
As current flows through the coil, magnetic fields develop around the coil. The ability of a magnetic field to do work depends on the design of the coil, as well as on the current passing through it. nine0016 Magnetic fields are indicated as lines around and through the coil.
The direction of the magnetic fields depends on the direction of the current, so a change in the current flowing through the coil will cause the magnetic fields to change direction in the same proportion as the frequency of the new current. 60 Hz AC will cause fields that change direction 60 times per second. 400kHz AC will cause magnetic fields that change direction 400,000 times per second.
When a metal that is a conductor is placed in a variable magnetic field (for example, a field generated by alternating current), a voltage is generated inside the metal (Faraday's Law). The induced voltage will result in a flow of electrons: a current! The current passes through the working piece of metal in the opposite direction to the voltage in the inductor.
This means that we can control the frequency of the current in the metal by controlling the frequency of the current in the inductor. nine0016
Since the current flows through the medium, there will be resistance to the movement of electrons in it. This resistance shows up as heat (Joule Heating Effect) Materials with more resistance to the movement of electrons will show more heat when current flows through them, but it is also possible to heat very high conductivity metals (eg copper) using induced currents. This phenomenon is critical for inductive heating.
What do we need for Induction heating?
All of the above tells us that we need two basic things for induction heating to appear:
- Changing magnetic fields
- An electrically conductive metal placed in a magnetic field
How is induction different from other heating methods?
There are several methods for heating an object without induction. The most common in industrial practice are gas ovens, electric ovens and salt baths.
These methods are all based on the transfer of heat to an object from a source (burner, heating element, liquid salt) through convection or radiation. After the surface of an object is heated, heat passes inward through thermal conduction. nine0016
Induction heating of objects does not rely on convection or radiation to deliver heat to the surface of the object. Instead, heat is generated on the surface of the object through the flow of current. The heat from the surface is then transferred to the interior of the object by conduction. The depth at which heat is directly generated by current generation depends on a parameter called the Electrical Reference Depth.
The electrical reference depth is very dependent on the frequency of the emerging current flowing in the object. A higher frequency will give a shallow electrical reference depth and a lower frequency will result in a larger electrical reference depth. This depth also depends on the electrical and magnetic properties of the object.
nine0016 Electric reference depth of high and low frequencies.
The Inductotherm Group takes advantage of these physical phenomena to create custom heating solutions for special products and applications.
Precise control of power, frequency and coil geometry allows the Inductotherm Group to design equipment with high levels of process control and reliability, regardless of application.
Induction Melting
For most processes, melting is the first step in producing a useful product, induction melting is fast and efficient. By changing the geometry of the induction coil, induction furnaces can be of various sizes - from a small cup of coffee to hundreds of tons of molten metal. Further, by adjusting the frequency and power, the Inductotherm group of companies can process almost all metals and materials, including iron, steel and stainless alloys, copper and its alloys, aluminum and silicon and others. Induction equipment is made to order for each individual application in order to be used most efficiently.
nine0016
Induction Vacuum Melt
Because induction heating involves the use of magnetic fields, the object to be heated must be physically insulated from the inductor with refractory or other non-conductive material. Magnetic fields will pass through this material to excite a voltage in the load contained within. This means that the item or materials can be heated under vacuum or in a carefully controlled atmosphere. This makes it possible to process very active metals (titanium, aluminium), special alloys, silicon, graphite and any other sensitive conductive materials. nine0016
Induction heating
Unlike combustion methods, induction heating is precisely controlled regardless of the volume of the object being heated. By varying the current, voltage, and frequency in the inductor, finely tuned heating can be obtained, excellent for precision applications such as case hardening, tempering and hardening, annealing, and other forms of heat treatment. A high level of control accuracy is critical for some applications such as automotive, aerospace, fiberglass, military, wire hardening and tempering.
Induction heating is excellent for specialty metal applications involving titanium, precious metals and advanced composites. The precise heat control that induction heating provides cannot be achieved in any other way. In addition, using the same base as vacuum heating in a crucible, induction heating can be performed in the atmosphere with continuous application. For example for annealing stainless steel tube. nine0016
High Frequency Induction Welding
When induction occurs using High Frequency (HF) current, even welding is possible. This application uses as shallow an electrical reference depth as possible when using high frequencies. In this case, a strip of metal is formed continuously and then passed through precisely calculated rolls, the purpose of which is to press the edges of the passed metal strips together to initiate welding. Just before passing through the rolls, the metal passes through an induction coil. In this case, the current flows along the geometric V formed by the edges of the tape instead of going outside the formed channel.
