Индукционная закалка внутренних шлицевых зубов
Ⅰ. Watch Internal Spline Induction Hardening in Operation
Видео: Localized induction heating of internal spline teeth using a customized bore inductor.
The video shows a circular metal component with internal spline teeth machined into its central bore. A compact induction coil is positioned near the splined opening, directing heat toward the internal tooth region.
Во время нагрева, the spline area becomes visibly red-hot while much of the surrounding component remains comparatively dark.
The demonstration highlights the use of a compact inductor for localized heating inside a toothed bore.
Детали приложения
| Элемент | Описание |
|---|---|
| Заготовка | Circular metal component with internal spline teeth |
| Treatment Area | Internal spline bore |
| Процесс | индукционное упрочнение |
| Метод нагрева | Локальный индукционный нагрев |
| Индуктор | Compact bore-type induction coil |
| Hardening Objective | Specified hardness distribution across the required internal spline surfaces |
The video identifies the process as induction hardening and describes consistent hardness across the spline teeth as a process objective. The visible footage shows the heating stage; the subsequent quenching method and final hardness results have not been verified.
Ⅱ. Suitable Workpieces and Industrial Applications
Internal splines provide a mechanical connection between mating components for torque transmission. Their tooth surfaces may experience contact pressure, repeated loading and relative movement during operation.
Для подходящих закаливаемых сталей, induction hardening can be used to treat selected spline surfaces without requiring the entire component to undergo the same hardening cycle.
Typical Workpieces
— Internally splined hubs.
— Splined sleeves and couplings.
— Transmission components with internal splines.
— Drivetrain components with splined connections.
— Custom mechanical parts requiring localized spline hardening.
Relevant Industries
Automotive and Drivetrain Manufacturing
Selected transmission and constant-velocity joint components contain internal splines. Induction hardening may be used where their design specifies localized hardened tooth surfaces.
Power Transmission Equipment
Splined hubs, couplings and related components transfer torque between connected shafts and assemblies. Surface hardening may be required according to their loading and wear conditions.
Construction and Heavy Machinery
Heavy-duty transmission components may incorporate internal splines. The required treatment depends on the steel grade, tooth geometry and operating conditions.
General Machinery Manufacturing
Custom splined sleeves, hubs and mechanical connections can also be evaluated for localized induction hardening.
The specific end use of the workpiece shown in the video has not been confirmed. These industries represent potential applications rather than verified uses of the demonstrated component.
Ⅲ. Customized Inductor Design for Internal Spline Hardening
Конструкция индуктора is a central consideration when heating internal spline teeth.
The tooth profile creates different electromagnetic coupling conditions at the tips, flanks and roots. A suitable inductor must work within the available bore space while producing a heating pattern appropriate to the specified hardened region.
Bore Geometry and Coil Clearance
The induction coil must be matched to the internal spline diameter, axial length, tooth profile and surrounding workpiece geometry.
Limited space inside the bore also affects coil construction, electrical connections and cooling arrangements.
Heating Distribution Across the Teeth
The required hardening pattern may cover the tooth flanks, корней, tips or a specified combination of these surfaces.
Heating conditions are influenced by coil geometry, рабочая частота, power and heating duration. These parameters must be evaluated together rather than selected independently.
A visibly heated spline does not establish that every part of the tooth profile has reached the required hardening condition.
Workpiece Fixtures and Positioning
The fixture supports and locates the workpiece relative to the inductor.
The mechanical arrangement must provide suitable access to the bore and maintain the required position during processing. Different spline sizes or profiles may require separate inductors and tooling.

Ⅳ. Heating Methods and Quenching Arrangement
The appropriate hardening method depends on spline length, required treatment area, material and production conditions.
Stationary Induction Heating
In a stationary arrangement, the workpiece and inductor remain at a defined relative position during heating.
This method may be suitable for a relatively short treatment region when the coil can produce the required heating pattern.
Scanning Induction Hardening
For longer spline bores or a defined axial treatment length, relative movement between the workpiece and inductor may be required.
The heating power, scanning speed and quenching sequence must be coordinated to obtain the specified hardened region.
The demonstrated video does not establish whether a complete stationary or scanning hardening sequence was used.
Quenching the Internal Spline Surfaces
Для подходящих закаливаемых сталей, the required surface region must reach the appropriate austenitizing condition before controlled quenching produces the intended hardened structure.
Internal tooth geometry affects how the quenchant reaches the heated surfaces. The cooling arrangement must therefore account for the tooth profile, bore access, required hardened depth and dimensional requirements.
Depending on the selected process, the system may use an integrated heating and quenching inductor assembly or a separate quenching arrangement.
The final hardness profile depends on the combined heating and quenching conditions, not on the induction power supply alone.
Ⅴ. Induction Hardening Equipment and Control Configuration
KOTRON supplies induction hardening equipment solutions that combine the heating system, customized tooling, quenching equipment and necessary control functions.
The equipment scope is selected according to the workpiece, hardening specification and production requirements.
| Системный компонент | Рекомендации по настройке |
|---|---|
| Индукционный источник питания | Power and frequency selected for the workpiece and heating requirements |
| Internal Bore Inductor | Customized to the spline profile, bore dimensions and treatment area |
| Workpiece Fixture | Support, locating and clamping arrangement |
| Система закалки | Quenchant delivery and cooling conditions matched to the process |
| Motion System | Stationary positioning or scanning movement where required |
| ЧПУ / PLC Control | Coordination of heating, movement and quenching operations |
| Охлаждение оборудования | Cooling arrangement matched to the electrical equipment and inductor |
| Production Automation | Загрузка, unloading and handling according to production needs |
Induction Power Supply and Digital Control
The power supply must be electrically matched to the selected inductor and provide the required heating output.
KOTRON’s available equipment includes DSP-controlled induction power supplies. According to the selected configuration, digital control supports regulation of heating parameters such as power, current and operating time.
For applications requiring production records, optional monitoring functions may include operating-parameter display, кривыми процесса, parameter-limit alarms and historical records.
These functions assist process supervision but do not directly establish the finished workpiece’s hardness or effective case depth.
Эталонные модели индукционных источников питания
Several induction power supply models are available for evaluating internal spline hardening applications. The appropriate selection depends on the spline geometry, Материал, требуемую закаленную область, case depth and production cycle.
The following models provide reference configurations for initial equipment selection.
| Модель | Мощность | Диапазон частот | Potential Application |
|---|---|---|---|
| XG-80 | 80 кВт | 20–40 кГц | Smaller internal spline components |
| XZG-160SCZ | 160 кВт | 1–50 кГц | Medium-sized internal spline applications |
| XZG-200SCN | 200 кВт | 5–20 кГц | Larger internal spline and internal-tooth components |
| XZG-250SCN | 250 кВт | 5–20 кГц | Larger workpieces with higher heating power requirements |
These configurations are provided as selection references rather than fixed recommendations for particular spline sizes.
The required power and frequency must be evaluated together with the inductor design, heating conditions and quenching process. A higher power rating does not automatically provide greater case depth or a more uniform hardened profile.
The power supply used in the video demonstration has not been identified as one of these models.
Specialized Power Supply Options
For certain tooth profiles, simultaneous dual-frequency heating may be evaluated to influence heating distribution across the tooth geometry.
Its suitability for internal splines depends on the workpiece, inductor and required hardening pattern. The demonstrated video does not establish the use of dual-frequency technology.
Where hardening and tempering are required in a coordinated production process, suitable multi-station and multi-frequency arrangements may also be evaluated.
Machine Movement and Automation
The mechanical arrangement may range from a manually loaded heating station to an integrated hardening system with controlled movement and automated handling.
Possible project-specific functions include programmable positioning, сканирование, automatic loading and unloading, and coordinated heating and quenching control.
The required configuration depends on component size, скорость производства, changeover requirements and existing production facilities.
Ⅵ. Selecting the Right Equipment for Internal Spline Teeth
Equipment selection begins with the internal spline geometry and the required hardening result.
The bore diameter alone is not sufficient to determine the induction power, frequency or coil design.
| Фактор выбора | Инженерное рассмотрение |
|---|---|
| Material and Steel Grade | Hardenability and required heat-treatment cycle |
| Bore Diameter | Available space and inductor clearance |
| Spline Tooth Profile | Heating distribution across tooth tips, flanks and roots |
| Spline Length | Heating coverage and possible scanning requirements |
| Требуемая защищенная зона | Position and extent of the treatment |
| Целевая твердость поверхности | Требуемые свойства обрабатываемой поверхности |
| Эффективная глубина корпуса | Heating and quenching process requirements |
| Производственные требования | Equipment layout, processing sequence and automation |
Hardness and Case-Depth Verification
For components requiring a defined hardness profile, the process should be established through suitable trials and inspection.
Depending on the specification, verification may include surface hardness measurements, hardness traverses and examination of the hardened layer.
Inspection positions should reflect the required functional surfaces of the spline, including the tooth flanks and roots where specified.
Results established for another gear, spline or internal bore cannot automatically be applied to a new workpiece.
For internal splines and other internal bores, KOTRON also offers a dedicated internal bore induction hardening machine for automotive and motorcycle precision components. Externally splined shafts can be treated with the spline shaft induction hardening machine.
Ⅶ. Часто задаваемые вопросы
Нажмите на вопрос, чтобы развернуть ответ.
Can induction hardening treat both the tooth flanks and roots of an internal spline?
A customized process can be developed for a specified hardening pattern that includes these regions. The achievable result depends on tooth geometry, Материал, heating conditions and quenching. Hardness distribution should be verified against the workpiece specification.
Does every internal spline require a specially designed induction coil?
The inductor must match the bore dimensions, required hardened area and available clearance. Different workpieces may share an inductor where their geometries and process requirements are compatible, but tooling suitability must be evaluated.
Is dual-frequency induction heating necessary?
Нет. Single-frequency heating may be suitable for an internal spline application. Dual-frequency technology is an additional option for selected tooth profiles and hardening requirements.
Can the system process different spline components?
Different parts may be processed within the designed mechanical and electrical range of the equipment. Changes in spline size or tooth profile may require different inductors, приспособления или настройки процесса.
Can the equipment be supplied with automatic handling and quenching?
Да. The equipment scope can include suitable quenching systems, programmable movement, process control and automated workpiece handling. These are configured according to the production application.
Ⅷ. Request a Customized Internal Spline Hardening Solution
For internal spline induction hardening, the most useful starting point is the workpiece drawing and the required treatment area.
Пожалуйста, пришлите нам:
— Чертеж или фотографии заготовки.
— Материал или марка стали.
— Spline bore diameter and length.
— Spline tooth profile or dimensions.
— Требуемая площадь закалки.
— Production quantity or cycle requirement.
Если уже определено, please also include the target surface hardness and effective case depth.
На основании этих подробностей, KOTRON can evaluate the induction power supply, customized bore inductor, оснастка для заготовки, quenching arrangement and required machine control or automation.
Need induction hardening for internal spline teeth?
Send your workpiece drawing and KOTRON will evaluate a customized internal spline induction hardening solution.







