US20090033008A1 - Quality warranty system in induction heat treatment facilities - Google Patents

Quality warranty system in induction heat treatment facilities Download PDF

Info

Publication number
US20090033008A1
US20090033008A1 US12/238,103 US23810308A US2009033008A1 US 20090033008 A1 US20090033008 A1 US 20090033008A1 US 23810308 A US23810308 A US 23810308A US 2009033008 A1 US2009033008 A1 US 2009033008A1
Authority
US
United States
Prior art keywords
heat treatment
products
hardened layer
treatment facilities
induction heat
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US12/238,103
Inventor
Takeaki Kokudai
Shintaro Suzuki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NTN Corp
Original Assignee
NTN Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NTN Corp filed Critical NTN Corp
Assigned to NTN CORPORATION reassignment NTN CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KOKUDAI, TAKEAKI, SUZUKI, SHINTARO
Publication of US20090033008A1 publication Critical patent/US20090033008A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/34Methods of heating
    • C21D1/42Induction heating
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/06Surface hardening
    • C21D1/09Surface hardening by direct application of electrical or wave energy; by particle radiation
    • C21D1/10Surface hardening by direct application of electrical or wave energy; by particle radiation by electric induction
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D11/00Process control or regulation for heat treatments
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D11/00Process control or regulation for heat treatments
    • C21D11/005Process control or regulation for heat treatments for cooling
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/28Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for plain shafts
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/40Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rings; for bearing races
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/25Process efficiency

Definitions

  • the present invention relates to a quality warranty system for controlling a heat treatment quality for use in induction heat treatment facilities, in which metallic products, which will become component parts such as, for example, bearing parts, constant velocity universal joint parts, various shafts or engine parts, are heated through the induction heat treatment.
  • induction heat treatment hardening or tempering is carried out by means of an induction heating.
  • the surface hardness and the depth of an effective hardened layer are required to be checked, but those items are required to be checked with the use of a hardness testing machine and, therefore, products so inspected can no longer be used. Accordingly, it has been a general practice that the quality inspection is based on a sampling inspection, and, provided that products being monitored fall within the range of uppermost and lowermost values, which have been set up, as shown in FIG. 3 , as a result of measurement of processing conditions conducted during the production, those products are deemed to be acceptable.
  • a non-destructive inspection using an eddy current is available, in which the use is made of a probe 51 , as shown in FIG. 4A , to measure a product W.
  • the product W cannot be measured except for a localized portion thereof and, accordingly, the application of the non-destructive inspection using the eddy current is limited particularly where the product W has a plurality of locations to be inspected as shown in FIG. 4B .
  • Patent Documents 1 and 2 discloses monitoring the state of heat treatment.
  • the present invention is intended to provide a quality warranty system utilizable in induction heat treatment facilities, in which the reliability of quality warranty can be increased because of the clarity of the processing conditions and the depth of the hardened layer in each of the products which have been heat treated, and in which selection and identification of defective products once they occur can be facilitated.
  • the quality warranty system in induction heat treatment facilities in which heat treatment of metallic products are carried out by induction heating them by means of a heating coil, connected with a radio frequency power source, and cooling them with a cooling apparatus, according to the present invention includes a monitoring apparatus for monitoring processing conditions in the induction heat treatment facilities during the heat treatment of each of the products, and a recording apparatus for recording information on the processing conditions, monitored by the monitoring apparatus, against an identification code of each of the products.
  • the quality warranty system may also include a hardened layer inspecting apparatus for inspecting on a non-destructive basis the depth of a hardened layer formed in each of the products as a result of the heat treatment.
  • the recording apparatus records information on the depth of the hardened layer, inspected by the hardened layer inspecting apparatus, and the information on the processing conditions, monitored by the monitoring apparatus, against the identification code of each of the products.
  • the processing conditions out of the processing conditions of the products and the depth of the hardened layer thereof can be ascertained.
  • the processing conditions since at least the processing conditions is recorded for each of the products, the reliability of quality can be increased.
  • the processing record corresponds to each of the products, selection of defective products when the latter occur and identification of a cause of defectiveness can be accomplished.
  • the hardened layer inspecting apparatus referred to above may be of any type, provided that the depth of the hardened layer can be inspected on a non-destructive basis, and can be employed in the form of, for example, a hardened layer inspecting apparatus of an eddy current type. Other than it, a hardened layer inspecting apparatus of an ultrasonic type can also be employed.
  • the use of the marking apparatus for applying a marking of the identification code to each of the products is preferred.
  • FIG. 1 is an explanatory diagram showing a conceptual construction of a quality warranty system in induction heat treatment facilities according to a preferred embodiment of the present invention
  • FIG. 2A is an explanatory diagram showing the manner of control in the quality warranty system according to the embodiment of the present invention.
  • FIG. 2B is an explanatory diagram showing the conventional manner of control
  • FIG. 3 is an explanatory diagram showing the relation between manufacture of products and processing condition according to the conventional control
  • FIG. 4A is an explanatory diagram showing examples measurement performed with a hardened layer inspecting apparatus of an eddy current type
  • FIG. 4B is another explanatory diagram showing examples measurement performed with a hardened layer inspecting apparatus of an eddy current type.
  • FIG. 5 is an explanatory diagram showing the relation between the product manufacture and the quality according to the conventional control.
  • a quality warranty system for use in induction heat treatment facilities is of a type, in which a monitoring apparatus 3 , a recording apparatus 4 and a marking apparatus 5 and, optionally, a hardened layer inspecting apparatus 2 are provided for use in the induction heat treatment facilities 1 for heat treating products W.
  • the induction heat treatment facilities are where a heat treatment of metallic products W, including hardening thereof, is performed by induction heating them by means of a heating coil 7 , connected with a radio frequency power source 6 , and cooling them in a cooling apparatus 8 and may be of a type capable of performing, for example, a tempering subsequent to the hardening or only a hardening.
  • a heat treatment line is formed extending from the heating coil 7 to the cooling apparatus 8 and then to the hardened layer inspecting apparatus 2 and the marking apparatus 5 by a transport apparatus 12 for transporting the products W.
  • the transport apparatus 12 is made up of a plurality of conveyors and/or loading apparatuses.
  • the hardened layer inspecting apparatus 2 and the marking apparatus 5 may not be arranged in the order specified above. Also, the hardened layer inspecting apparatus 2 is not always essential and may therefore be dispensed with.
  • the products W may be any product, provided that they can be heat treated by means of an induction heating and may be mechanical component parts such as, for example, bearing parts (bearing rings and so on), constant velocity universal joint parts (joint members and so on), connecting rods, various shafts or engine parts.
  • bearing parts bearing rings and so on
  • constant velocity universal joint parts joint members and so on
  • connecting rods various shafts or engine parts.
  • the products W are supported by device 10 , for example, a support table relative to the heating coil 7 .
  • the support device 10 is of a type that is driven by a motor 11 to rotate the products W within the heating coil 7 .
  • the products W may be heated by the heating coil 7 either all at a time or one at a time.
  • the heating coil 7 may be of a type capable of induction heating the products W while the latter are relatively moved in a direction, for example, axially of each product.
  • the cooling apparatus 8 is an apparatus in which the products W, which have been heat treated, are cooled for hardening and includes a nozzle 8 a for discharging a coolant such as, for example, a cooling liquid onto the products W, a coolant supply source 8 b from which the coolant is supplied to the nozzle 8 a .
  • This cooling apparatus 8 may be of a type capable of cooling the products W while the latter are immersed in a bath of a cooling liquid.
  • a production control apparatus 20 is an apparatus for controlling the induction heat treatment facilities 1 in their entirety and controls, for example, the recording apparatus 4 and the marking apparatus 5 .
  • the monitoring apparatus 3 is an apparatus for monitoring the state of heating in the induction heat treatment facilities 1 during the heat treatment of the individual products W. Items of the heating state to be monitored by the monitoring apparatus 3 arc properly determined in dependence on, for example, the type of the products W and/or the heat treatment method used. Those items of the heating state to be monitored include at least one of the followings (a) to (c):
  • Monitoring of those items is carried out by monitoring respective outputs generated from detectors provided in the radio frequency power source 6 and the cooling apparatus 8 .
  • the hardened layer inspecting apparatus 2 is an apparatus for measuring, on a non-destructive basis, the depth of a hardened layer Wa formed as a result of heat treatment of the individual products W and is employed in the form of, for example, an eddy current type hardened layer inspecting apparatus.
  • the hardened layer inspecting apparatus 2 may be an ultrasonic type hardened layer inspecting apparatus.
  • the hardened layer inspecting apparatus 2 employed in the illustrated embodiment is in the form of the eddy current type and includes probes 2 a , which can be neared to the products W, and a data processing unit 2 b for processing detection signals from the probes 2 a to provide a value of the depth of the hardened layer.
  • the hardened layer inspecting apparatus 2 is chosen to be of a type operable to measure the depth of a portion of the hardened layer Wa of the products W, which forms a representative portion thereof.
  • the site of measurement may lie either at one location or a plurality of locations and, where the site of measurement includes a plurality of locations, the measurement may be made with the use of a plurality of probes 2 a one for each location or, alternatively, the measurement may be made by successively shifting the single probe 2 a from one location to another.
  • the recording apparatus 4 is an apparatus for recording information, which is related with the processing conditions such as, for example, an electric power supplied to the heating coil 7 monitored by the monitoring apparatus 3 , and, optionally, information, which is related with the depth of the hardened layer inspected by the hardened layer inspecting apparatus 2 , in correspondence with the identification code of the individual products W.
  • the recording apparatus 4 may record, other than the information related with the processing conditions, information related with settings of various parts of the induction heat treatment facilities 1 such as, for example, information related with settings of the electric power of the radio frequency power source 6 to be supplied to the heating coil 7 and the frequency thereof, in correspondence with the identification code of the products W.
  • the information related with the settings is controlled by the production control apparatus 20 and are then transferred to the recording apparatus 4 .
  • the recording apparatus 4 is a so-called database and includes a storage unit 4 a for storing the previously discussed identification codes, the processing conditions and the information related with the depth of the hardened layer and a stored information control unit 4 b which is a database management system for processing inputs to and outputs from the storage unit 4 a.
  • the recording apparatus 4 may be the one provided in the same computer as the production control apparatus 20 , in which case the use of the production control apparatus 20 may be dispensed with. Also, the recording apparatus 4 may be provided in a computer separate from the production control apparatus 20 and may be connected therewith through a network.
  • the marking apparatus 5 is an apparatus for applying a marking M, which forms the identification code that is recorded by the recording apparatus 4 , to a corresponding product W and may be of a type capable of, for example, imprinting the marking M.
  • This marking apparatus 5 may be of any type, provided that it can apply the identification code to the product W, and can be employed in the form of an apparatus capable of applying the identification code in any one of various methods other than imprinting.
  • the marking apparatus 5 may be of a type capable of applying to the product the identification code in the form of, for example, a code such as, for example, a bar codes, or an IC tag.
  • the identification code is acquired from, for example, the production control apparatus 20 , but may acquire from the recording apparatus 4 rather than from the production control apparatus 20 .
  • the operation of the above described construction will now be described.
  • the products W are heat treated by the heating coil 7 excited by the radio frequency power source 6 and are then hardened when cooled by the cooling apparatus 8 .
  • the processing conditions which are represented by the electric power of the radio frequency power source 6 to be supplied to the heating coil 7 and the frequency thereof, are monitored by the monitoring apparatus 3 and values so monitored are recorded in the recorded apparatus 4 each time the individual products are heat treated.
  • the identification codes corresponding to the recording are applied to the products W and, in the recording apparatus 4 , the above described processing information is recorded in correspondence with the identification codes.
  • the depth of the representative portion of each of the products W, which have been heat treated, may be measured on a non-destructive basis by the hardened layer inspecting apparatus 2 of the eddy current type.
  • the depth of the hardened layer so measured is ascertained by a determining module (not shown) that it falls within a required depth range (that is, a preset range of depth) and is recorded by the recording apparatus 4 together with the processing information in correspondence with the identification information.
  • FIG. 2A illustrates a concept of control of the heat treatment applied to the products W according to this embodiment of the present invention
  • FIG. 2B illustrates a concept of the conventional control.
  • the processing information and, optionally, the depth of the hardened layer are recorded together with the product identification information. Because of this, the reliability of quality increases. Also, since for each of the products W, the product and the processing record are associated with each other, selection of defective products, when the latter occur, and identification of a cause of defectiveness can be accomplished.
  • the marking apparatus 5 can be dispensed with, in which case the identification code applied beforehand to the corresponding product is read out by the monitoring apparatus 3 or the production control apparatus 20 .

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
  • General Induction Heating (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

To provide a quality warranty system in the induction heat treatment facilities, in which the reliability of quality warranty can be increased because of the clarity of the processing conditions in each of the products which have been heat treated, and in which selection and identification of defective products once they occur can be facilitated. In the induction heat treatment facilities (1), there are provided a monitoring apparatus (3) for monitoring processing conditions in the induction heat treatment facilities (1) during the heat treatment of each of the products (W), and a recording apparatus (4) for recording information on the processing conditions, monitored by the monitoring apparatus (3), against an identification code of each of the products (W).

Description

    CROSS-REFERENCE TO RELATED APPLICATIONS
  • This application is a Continuation Application of International Application PCT/JP2007/000299 filed Mar. 26, 2007, which claims the benefit of priority Japanese Application No. 2006-086053 filed Mar. 27, 2006, the disclosures of which are incorporated herein by reference.
  • BACKGROUND OF THE INVENTION
  • The present invention relates to a quality warranty system for controlling a heat treatment quality for use in induction heat treatment facilities, in which metallic products, which will become component parts such as, for example, bearing parts, constant velocity universal joint parts, various shafts or engine parts, are heated through the induction heat treatment.
  • In the induction heat treatment, hardening or tempering is carried out by means of an induction heating. During the inspection of the quality of heat treatment, the surface hardness and the depth of an effective hardened layer are required to be checked, but those items are required to be checked with the use of a hardness testing machine and, therefore, products so inspected can no longer be used. Accordingly, it has been a general practice that the quality inspection is based on a sampling inspection, and, provided that products being monitored fall within the range of uppermost and lowermost values, which have been set up, as shown in FIG. 3, as a result of measurement of processing conditions conducted during the production, those products are deemed to be acceptable.
  • Also, for the inspection of the effective hardened layer, a non-destructive inspection using an eddy current is available, in which the use is made of a probe 51, as shown in FIG. 4A, to measure a product W. However, with this non-destructive inspection, the product W cannot be measured except for a localized portion thereof and, accordingly, the application of the non-destructive inspection using the eddy current is limited particularly where the product W has a plurality of locations to be inspected as shown in FIG. 4B.
  • It is to be noted that the following Patent Documents 1 and 2 discloses monitoring the state of heat treatment.
  • [Patent Document 1]
  • Japanese Laid-open Patent Publication No. 2001-226712
  • [Patent Document 2]
  • Japanese Laid-open Patent Publication No. 2001-294937
  • Since the quality inspection of the products which have been heated through the induction heat treatment is generally based on a sampling inspection, there is the possibility, as can readily be understood from FIG. 3, that some of the products not sampled for inspection may contain defective products that are caught up in and packaged for marketing together with those non-sampled products. Also, as shown in FIG. 5, once a defective product has been found during the sampling quality inspection, it is not possible to find where the defective product appeared and discrimination is not easy within one and the same lot, requiring all of the products to be discarded. In addition, even though the details of defectiveness could be identified, it is not easy to ascertain the cause (change in facilities or processing conditions) of such defectiveness.
  • SUMMARY OF THE INVENTION
  • In view of the foregoing, the present invention is intended to provide a quality warranty system utilizable in induction heat treatment facilities, in which the reliability of quality warranty can be increased because of the clarity of the processing conditions and the depth of the hardened layer in each of the products which have been heat treated, and in which selection and identification of defective products once they occur can be facilitated.
  • The quality warranty system in induction heat treatment facilities, in which heat treatment of metallic products are carried out by induction heating them by means of a heating coil, connected with a radio frequency power source, and cooling them with a cooling apparatus, according to the present invention includes a monitoring apparatus for monitoring processing conditions in the induction heat treatment facilities during the heat treatment of each of the products, and a recording apparatus for recording information on the processing conditions, monitored by the monitoring apparatus, against an identification code of each of the products.
  • In a preferred embodiment of the present invention, the quality warranty system may also include a hardened layer inspecting apparatus for inspecting on a non-destructive basis the depth of a hardened layer formed in each of the products as a result of the heat treatment. In this case, the recording apparatus records information on the depth of the hardened layer, inspected by the hardened layer inspecting apparatus, and the information on the processing conditions, monitored by the monitoring apparatus, against the identification code of each of the products.
  • According to the foregoing construction, when the identification code, applied by a marking apparatus to the products, is checked against the contents recorded by the recording apparatus, at least the processing conditions out of the processing conditions of the products and the depth of the hardened layer thereof can be ascertained. In such case, since at least the processing conditions is recorded for each of the products, the reliability of quality can be increased. Also, since the processing record corresponds to each of the products, selection of defective products when the latter occur and identification of a cause of defectiveness can be accomplished.
  • The hardened layer inspecting apparatus referred to above may be of any type, provided that the depth of the hardened layer can be inspected on a non-destructive basis, and can be employed in the form of, for example, a hardened layer inspecting apparatus of an eddy current type. Other than it, a hardened layer inspecting apparatus of an ultrasonic type can also be employed.
  • Also, the use of the marking apparatus for applying a marking of the identification code to each of the products is preferred.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • In any event, the present invention will become more clearly understood from the following description of preferred embodiments thereof, when taken in conjunction with the accompanying drawings. However, the embodiments and the drawings are given only for the purpose of illustration and explanation, and are not to be taken as limiting the scope of the present invention in any way whatsoever, which scope is to be determined by the appended claims. In the accompanying drawings, like reference numerals are used to denote like parts throughout the several views, and:
  • FIG. 1 is an explanatory diagram showing a conceptual construction of a quality warranty system in induction heat treatment facilities according to a preferred embodiment of the present invention;
  • FIG. 2A is an explanatory diagram showing the manner of control in the quality warranty system according to the embodiment of the present invention;
  • FIG. 2B is an explanatory diagram showing the conventional manner of control;
  • FIG. 3 is an explanatory diagram showing the relation between manufacture of products and processing condition according to the conventional control;
  • FIG. 4A is an explanatory diagram showing examples measurement performed with a hardened layer inspecting apparatus of an eddy current type;
  • FIG. 4B is another explanatory diagram showing examples measurement performed with a hardened layer inspecting apparatus of an eddy current type; and
  • FIG. 5 is an explanatory diagram showing the relation between the product manufacture and the quality according to the conventional control.
  • DESCRIPTION OF THE PREFERED EMBODIMENTS
  • A preferred embodiment of the present invention will be described in detail with particular reference to FIGS. 1 and 2. A quality warranty system for use in induction heat treatment facilities is of a type, in which a monitoring apparatus 3, a recording apparatus 4 and a marking apparatus 5 and, optionally, a hardened layer inspecting apparatus 2 are provided for use in the induction heat treatment facilities 1 for heat treating products W.
  • The induction heat treatment facilities are where a heat treatment of metallic products W, including hardening thereof, is performed by induction heating them by means of a heating coil 7, connected with a radio frequency power source 6, and cooling them in a cooling apparatus 8 and may be of a type capable of performing, for example, a tempering subsequent to the hardening or only a hardening. A heat treatment line is formed extending from the heating coil 7 to the cooling apparatus 8 and then to the hardened layer inspecting apparatus 2 and the marking apparatus 5 by a transport apparatus 12 for transporting the products W. The transport apparatus 12 is made up of a plurality of conveyors and/or loading apparatuses. The hardened layer inspecting apparatus 2 and the marking apparatus 5 may not be arranged in the order specified above. Also, the hardened layer inspecting apparatus 2 is not always essential and may therefore be dispensed with.
  • The products W may be any product, provided that they can be heat treated by means of an induction heating and may be mechanical component parts such as, for example, bearing parts (bearing rings and so on), constant velocity universal joint parts (joint members and so on), connecting rods, various shafts or engine parts.
  • The products W are supported by device 10, for example, a support table relative to the heating coil 7. In the instance as shown, the support device 10 is of a type that is driven by a motor 11 to rotate the products W within the heating coil 7. The products W may be heated by the heating coil 7 either all at a time or one at a time. The heating coil 7 may be of a type capable of induction heating the products W while the latter are relatively moved in a direction, for example, axially of each product.
  • The cooling apparatus 8 is an apparatus in which the products W, which have been heat treated, are cooled for hardening and includes a nozzle 8 a for discharging a coolant such as, for example, a cooling liquid onto the products W, a coolant supply source 8 b from which the coolant is supplied to the nozzle 8 a. This cooling apparatus 8 may be of a type capable of cooling the products W while the latter are immersed in a bath of a cooling liquid.
  • A production control apparatus 20 is an apparatus for controlling the induction heat treatment facilities 1 in their entirety and controls, for example, the recording apparatus 4 and the marking apparatus 5.
  • The monitoring apparatus 3 is an apparatus for monitoring the state of heating in the induction heat treatment facilities 1 during the heat treatment of the individual products W. Items of the heating state to be monitored by the monitoring apparatus 3 arc properly determined in dependence on, for example, the type of the products W and/or the heat treatment method used. Those items of the heating state to be monitored include at least one of the followings (a) to (c):
  • a) The electric power to be supplied from the radio frequency power source 6 to the heating coil 7 and/or the frequency of the radio frequency power source 6;
  • b) The position and/or the number of revolutions of the products W being heated relative to the heating coil 7; and
  • c) The flow and/or the temperature of a hardening cooling liquid in the cooling apparatus 8.
  • Monitoring of those items is carried out by monitoring respective outputs generated from detectors provided in the radio frequency power source 6 and the cooling apparatus 8.
  • The hardened layer inspecting apparatus 2 is an apparatus for measuring, on a non-destructive basis, the depth of a hardened layer Wa formed as a result of heat treatment of the individual products W and is employed in the form of, for example, an eddy current type hardened layer inspecting apparatus. The hardened layer inspecting apparatus 2 may be an ultrasonic type hardened layer inspecting apparatus. The hardened layer inspecting apparatus 2 employed in the illustrated embodiment is in the form of the eddy current type and includes probes 2 a, which can be neared to the products W, and a data processing unit 2 b for processing detection signals from the probes 2 a to provide a value of the depth of the hardened layer.
  • The hardened layer inspecting apparatus 2 is chosen to be of a type operable to measure the depth of a portion of the hardened layer Wa of the products W, which forms a representative portion thereof. The site of measurement may lie either at one location or a plurality of locations and, where the site of measurement includes a plurality of locations, the measurement may be made with the use of a plurality of probes 2 a one for each location or, alternatively, the measurement may be made by successively shifting the single probe 2 a from one location to another.
  • The recording apparatus 4 is an apparatus for recording information, which is related with the processing conditions such as, for example, an electric power supplied to the heating coil 7 monitored by the monitoring apparatus 3, and, optionally, information, which is related with the depth of the hardened layer inspected by the hardened layer inspecting apparatus 2, in correspondence with the identification code of the individual products W. The recording apparatus 4 may record, other than the information related with the processing conditions, information related with settings of various parts of the induction heat treatment facilities 1 such as, for example, information related with settings of the electric power of the radio frequency power source 6 to be supplied to the heating coil 7 and the frequency thereof, in correspondence with the identification code of the products W. The information related with the settings is controlled by the production control apparatus 20 and are then transferred to the recording apparatus 4.
  • The recording apparatus 4 is a so-called database and includes a storage unit 4 a for storing the previously discussed identification codes, the processing conditions and the information related with the depth of the hardened layer and a stored information control unit 4 b which is a database management system for processing inputs to and outputs from the storage unit 4 a.
  • The recording apparatus 4 may be the one provided in the same computer as the production control apparatus 20, in which case the use of the production control apparatus 20 may be dispensed with. Also, the recording apparatus 4 may be provided in a computer separate from the production control apparatus 20 and may be connected therewith through a network.
  • The marking apparatus 5 is an apparatus for applying a marking M, which forms the identification code that is recorded by the recording apparatus 4, to a corresponding product W and may be of a type capable of, for example, imprinting the marking M. This marking apparatus 5 may be of any type, provided that it can apply the identification code to the product W, and can be employed in the form of an apparatus capable of applying the identification code in any one of various methods other than imprinting. The marking apparatus 5 may be of a type capable of applying to the product the identification code in the form of, for example, a code such as, for example, a bar codes, or an IC tag. In this marking apparatus 5, the identification code is acquired from, for example, the production control apparatus 20, but may acquire from the recording apparatus 4 rather than from the production control apparatus 20.
  • The operation of the above described construction will now be described. The products W are heat treated by the heating coil 7 excited by the radio frequency power source 6 and are then hardened when cooled by the cooling apparatus 8.
  • During this heat treatment, the processing conditions, which are represented by the electric power of the radio frequency power source 6 to be supplied to the heating coil 7 and the frequency thereof, are monitored by the monitoring apparatus 3 and values so monitored are recorded in the recorded apparatus 4 each time the individual products are heat treated. The identification codes corresponding to the recording are applied to the products W and, in the recording apparatus 4, the above described processing information is recorded in correspondence with the identification codes.
  • The depth of the representative portion of each of the products W, which have been heat treated, may be measured on a non-destructive basis by the hardened layer inspecting apparatus 2 of the eddy current type. The depth of the hardened layer so measured is ascertained by a determining module (not shown) that it falls within a required depth range (that is, a preset range of depth) and is recorded by the recording apparatus 4 together with the processing information in correspondence with the identification information.
  • FIG. 2A illustrates a concept of control of the heat treatment applied to the products W according to this embodiment of the present invention and FIG. 2B illustrates a concept of the conventional control.
  • As can readily be understood from those figures, in the quality warranty system according to the foregoing embodiment, for each of the products W the processing information and, optionally, the depth of the hardened layer are recorded together with the product identification information. Because of this, the reliability of quality increases. Also, since for each of the products W, the product and the processing record are associated with each other, selection of defective products, when the latter occur, and identification of a cause of defectiveness can be accomplished.
  • It is to be noted that the marking apparatus 5 can be dispensed with, in which case the identification code applied beforehand to the corresponding product is read out by the monitoring apparatus 3 or the production control apparatus 20.

Claims (5)

1. A quality warranty system in induction heat treatment facilities, in which heat treatment of metallic products are carried out by induction heating them by means of a heating coil, connected with a radio frequency power source, and cooling them with a cooling apparatus, which system comprises:
a monitoring apparatus for monitoring processing conditions in the induction heat treatment facilities during heat treatment of each of the products; and
a recording apparatus for recording information on the processing conditions, monitored by the monitoring apparatus, against an identification code of each of the products.
2. The quality warranty system in induction heat treatment facilities as claimed in claim 1, further comprising a hardened layer inspecting apparatus for inspecting on a non-destructive basis the depth of a hardened layer formed in each of the products as a result of the heat treatment and wherein the recording apparatus records information on the depth of a hardened layer, inspected by the hardened layer inspecting apparatus, and information on the processing conditions, monitored by the monitoring apparatus, against the identification code of each of the products.
3. The quality warranty system in induction heat treatment facilities as claimed in claim 2, wherein the hardened layer inspecting apparatus is a hardened layer inspecting apparatus of an eddy current type.
4. The quality warranty system in induction heat treatment facilities as claimed in claim 1, further comprising a marking apparatus for applying a marking of the identification code to each of the products.
5. The quality warranty system in induction heat treatment facilities as claimed in claim 1, wherein the monitoring apparatus monitors at least one of the following items (a) to (c):
a) an electric power to be supplied from a radio frequency power source 6 to a heating coil 7 and/or the frequency of the radio frequency power source 6;
b) the position and/or the number of revolutions of the products W being heated relative to the heating coil 7; and
c) the flow and/or the temperature of a hardening cooling liquid in the cooling apparatus 8.
US12/238,103 2006-03-27 2008-09-25 Quality warranty system in induction heat treatment facilities Abandoned US20090033008A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2006086053A JP2007262450A (en) 2006-03-27 2006-03-27 Quality-guarantee system in high frequency induction heating facility
JP2006-086053 2006-03-27
PCT/JP2007/000299 WO2007111021A1 (en) 2006-03-27 2007-03-26 Quality guarantee system for high frequency heat treatment equipment

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2007/000299 Continuation-In-Part WO2007111021A1 (en) 2006-03-27 2007-03-26 Quality guarantee system for high frequency heat treatment equipment

Publications (1)

Publication Number Publication Date
US20090033008A1 true US20090033008A1 (en) 2009-02-05

Family

ID=38540956

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/238,103 Abandoned US20090033008A1 (en) 2006-03-27 2008-09-25 Quality warranty system in induction heat treatment facilities

Country Status (4)

Country Link
US (1) US20090033008A1 (en)
JP (1) JP2007262450A (en)
CN (1) CN101410534A (en)
WO (1) WO2007111021A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2466195C1 (en) * 2011-06-16 2012-11-10 Государственное образовательное учреждение высшего профессионального образования "Тольяттинский государственный университет" Method of automatic diagnostics and control of thermal power processing of low stiff axisymmetrical parts, and device for its implementation
US20160174300A1 (en) * 2014-12-11 2016-06-16 Neturen Co., Ltd. Heat treatment apparatus
WO2019016100A1 (en) * 2017-07-17 2019-01-24 Ald Vacuum Technologies Gmbh Method and furnace for the thermochemical treatment of metal workpieces

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5522661B2 (en) * 2009-12-16 2014-06-18 株式会社ミヤデン High frequency induction heating device
KR20140134997A (en) * 2013-05-15 2014-11-25 박종규 High frequency heat treatment apparatus for surface hardening
WO2017090795A1 (en) * 2015-11-26 2017-06-01 박종규 Apparatus for high-frequency heat treatment of ball studs, having eddy-current-testing total inspection function
KR101727726B1 (en) * 2015-11-26 2017-05-02 박종규 High-frequency heat treatment equipment of stub shaft with eddy current inspection type lot test function
JP2017226873A (en) * 2016-06-22 2017-12-28 Ntn株式会社 Method of manufacturing bearing component
DE102019211862A1 (en) * 2019-08-07 2021-02-11 Robert Bosch Gmbh Process for inductive heat treatment and procedural arrangement for carrying out the process
KR102322901B1 (en) * 2019-09-04 2021-11-08 임기현 Heat Treatment Automatic System and Method Thereof

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5968293A (en) * 1996-09-12 1999-10-19 Midland Steel Products Co. Method and apparatus for heat treating and straightening structural members

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0238518A (en) * 1988-07-27 1990-02-07 Daido Steel Co Ltd Method for treating high frequency quenching
JPH02141656A (en) * 1988-11-24 1990-05-31 Katsuhiro Ota Quality control method for member whose surface part is quenched and hardened
JP3499498B2 (en) 2000-04-10 2004-02-23 富士電子工業株式会社 Induction heat treatment equipment
JP4365536B2 (en) * 2001-02-19 2009-11-18 Jfeスチール株式会社 Steel production process abnormality judgment device
JP4365537B2 (en) * 2001-02-20 2009-11-18 Jfeスチール株式会社 Steel product quality control equipment

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5968293A (en) * 1996-09-12 1999-10-19 Midland Steel Products Co. Method and apparatus for heat treating and straightening structural members

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2466195C1 (en) * 2011-06-16 2012-11-10 Государственное образовательное учреждение высшего профессионального образования "Тольяттинский государственный университет" Method of automatic diagnostics and control of thermal power processing of low stiff axisymmetrical parts, and device for its implementation
US20160174300A1 (en) * 2014-12-11 2016-06-16 Neturen Co., Ltd. Heat treatment apparatus
US10568167B2 (en) * 2014-12-11 2020-02-18 Neturen Co., Ltd. Heat treatment apparatus
WO2019016100A1 (en) * 2017-07-17 2019-01-24 Ald Vacuum Technologies Gmbh Method and furnace for the thermochemical treatment of metal workpieces

Also Published As

Publication number Publication date
WO2007111021A1 (en) 2007-10-04
JP2007262450A (en) 2007-10-11
CN101410534A (en) 2009-04-15

Similar Documents

Publication Publication Date Title
US20090033008A1 (en) Quality warranty system in induction heat treatment facilities
US7525430B2 (en) Machine components having IC tags, quality control method and abnormality detecting system
US9964520B2 (en) Surface property inspection device and method
EP1576335B1 (en) Monitoring wall thickness
JPWO2017199959A1 (en) Surface treatment method and surface treatment device
KR101579018B1 (en) Steel tube production control method
US20110106460A1 (en) Automated component verification system
JPWO2018211879A1 (en) Surface treatment method and surface treatment device
JP2008032681A (en) Inspection method of rolling device component, and inspection device for rolling device component
Isakov et al. Large-Scale Fatigue Testing Based on the Rotating Beam Method
JP2006291247A (en) Heat treatment method, method for producing thin member for bearing, thin member for bearing and thrust bearing
CN117007946B (en) Automatic test management method and related device for PCBA
JP2003121424A (en) Inspection method and device of lining pipe
JP5318354B2 (en) Method and apparatus for quenching quality control of shaft
JP5318355B2 (en) Hardening quality control method and apparatus for constant velocity joint outer ring
JP2020186921A (en) Inspection method of surface layer of steel material and steel material surface layer inspection system
JP5619952B2 (en) Manufacturing method of constant velocity joint outer ring
JP2762157B2 (en) Inspection method for compound layer
CN209292453U (en) Continuous heat production equipment applied to copper pipe production
JP2008032682A (en) Method and apparatus for inspecting rolling device component
JP2007239037A (en) Induction heating and hardening of hub bearing
JP2008174806A (en) High-frequency heat treatment apparatus for constant-velocity joint outer ring
Ceurter et al. BARKHAUSEN NOISE INSPECTION.
JPH01291149A (en) Detecting method for defect of material to be inspected
KR20150087472A (en) Automation apparatus and treating method for eddy current test

Legal Events

Date Code Title Description
AS Assignment

Owner name: NTN CORPORATION, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KOKUDAI, TAKEAKI;SUZUKI, SHINTARO;REEL/FRAME:021622/0100

Effective date: 20080910

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION