NL2032520B1 - Method and inspection station for recursive inspection of rolls - Google Patents

Method and inspection station for recursive inspection of rolls Download PDF

Info

Publication number
NL2032520B1
NL2032520B1 NL2032520A NL2032520A NL2032520B1 NL 2032520 B1 NL2032520 B1 NL 2032520B1 NL 2032520 A NL2032520 A NL 2032520A NL 2032520 A NL2032520 A NL 2032520A NL 2032520 B1 NL2032520 B1 NL 2032520B1
Authority
NL
Netherlands
Prior art keywords
inspection
roll
threshold value
location
roller
Prior art date
Application number
NL2032520A
Other languages
Dutch (nl)
Inventor
Jacobus Wilhelmus Maria Van Kollenburg Rudolphus
Mul Sander
Original Assignee
Lismar Eng B V
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 Lismar Eng B V filed Critical Lismar Eng B V
Priority to NL2032520A priority Critical patent/NL2032520B1/en
Application granted granted Critical
Publication of NL2032520B1 publication Critical patent/NL2032520B1/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/11—Analysing solids by measuring attenuation of acoustic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
    • G01N29/4409—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by comparison
    • G01N29/4427—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by comparison with stored values, e.g. threshold values
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
    • G01N29/4445—Classification of defects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
    • G01N29/48—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by amplitude comparison
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B38/00—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/02—Indexing codes associated with the analysed material
    • G01N2291/023—Solids
    • G01N2291/0234—Metals, e.g. steel
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/02—Indexing codes associated with the analysed material
    • G01N2291/028—Material parameters
    • G01N2291/0289—Internal structure, e.g. defects, grain size, texture
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/04—Wave modes and trajectories
    • G01N2291/044—Internal reflections (echoes), e.g. on walls or defects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/26—Scanned objects
    • G01N2291/263—Surfaces
    • G01N2291/2634—Surfaces cylindrical from outside

Landscapes

  • Physics & Mathematics (AREA)
  • Biochemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Acoustics & Sound (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

The invention relates to a method for recursive inspection of rolls, in particular mill rolls, wherein each roll comprises a substantially cylindrical outer surface, wherein 5 the method makes use of an inspection station, the method performed in each inspection run comprising the steps of positioning a roll to be inspected in the receiving space of the inspection station, identifying the roll, determining an initial threshold value and/or loading from the database local threshold values, scanning the quality of the material of at least part of the mantle, determining and comparing 10 the determined amplitude per location and allowing the roll to be released for operation or reject the roll.

Description

Method and inspection station for recursive inspection of rolls
The invention relates to a method for recursive inspection of rolls, in particular mill rolls. The invention further relates to an inspection station for recursive inspection of rolls, preferably for performing the method according to the invention.
In steel rolling mill rolls are used for rolling and forming the hot steel into a desired, typically flat configuration. During these operations temperatures of up to 1050 degrees Celsius are not uncommon. The rolls used for rolling the hot steel are therefor subject to wear. The quality of the roll is important for the safety of the operators running the steel rolling process and also for the quality of the rolled steel. In particular the surface quality of the roll used is of importance for the surface quality of the rolled steel. Therefore, after four to eight hours of operation the quality of the rolls needs to be inspected for defects and grinded again to ensure a good surface quality of the roll. During inspection and grinding the rolls cannot be used in operation. A downside of current methods of inspection is that all possible defects need to be manually checked by an inspector before the roll is released and allowed back in operation again. The inspector is not always present and thus rolls need to stand idle for a while before an inspector has given their approval whether or not any detected defects are acceptable and thus whether or not the roll may proceed in operation. The lead time for a roll in inspection is relatively long, which is disadvantageous for the process. In the known processes it is very common that the same defect in the roll is inspected multiple times by the inspector, because the defect is safe enough for the roll to maintain in operation but each time the roll is up for inspection the acceptable defect is identified again. The inspection step is very time consuming and costly and the currently known processes cannot avoid duplication of work. lt is an object of the present invention to provide an improved way of inspection rolls which has a shorter lead time.
The invention thereto provides a method for recursive inspection of rolls, in particular mill rolls, wherein each roll comprises a substantially cylindrical outer surface (mantle), wherein the method makes use of an inspection station, said inspection station comprising:
e at least one receiving space for receiving at least one roll, in particular mill roll, which is to be inspected; e at least one inspection element comprising at least one transmitter and at least one receiver, wherein the transmitter is configured to send at least one signal, in particular an ultrasonic signal, to the surface and/or subsurface of the mantle (of the roll) and/or to the transition zone of the roll, and wherein the receiver is configured to receive at least part of a signal reflected by said surface and/or subsurface of the mantle and/or transition zone of the roll; e at least one control unit connected with at least one inspection element and configured to determine an amplitude of the reflected signal per location of the mantle of the roll; and e at least one database for storing data of each performed inspection run. The database may also be configured for storing the determined amplitudes per location during the inspection run.
The method according to the present invention performed in each inspection run comprises the steps of:
A. positioning a roll to be inspected in the receiving space of the inspection station;
B. identifying the roll;
C. determining an initial threshold value for an allowable amplitude of reflected signals for each location of the mantle of the identified roll and storing this threshold value in the database and/or loading from the database local threshold values for an allowable amplitude of reflected signals for each location of the mantle of the identified roll from the previous inspection run as stored in the database;
D. scanning the quality of the material of at least part of the mantle (substantially entire mantle) of the roll by the inspection element via transmitting at least one signal from the transmitter to the surface of the mantle of the roll, and receiving at least part of a reflected signal from the transmitted signal, wherein the reflected signal is reflected by the surface and/or subsurface of the mantle of the roll and/or by the transition zone of the roll;
E. determining the amplitude of at least one signal reflected during step D of at least one location of the mantle of the roll (preferably all locations, realtime or after the scanning took place);
F. comparing the determined amplitude per location (location specific amplitude) with the stored initial threshold values and/or stored local threshold values per location of the mantle of the roll, and: a. allowing the roll to be released for operation in case the determined amplitude per location falls within the stored threshold value for that location; or b. determine the difference with the initial threshold value and/or stored local threshold values in case the determined amplitude of at least one location exceeds the stored initial threshold value or local threshold value and based upon the determined difference and/or based upon the location of the exceeded threshold value on the mantle, either: i. determine a local (location specific) threshold value for at least one location and overwrite the stored initial threshold value or previous local threshold value by said new local threshold value to an allowable amplitude for the specific location of the mantle of the roll and store the new local threshold value in the database; or fi. reject the roll.
The method according to the present invention saves costs by reducing lead time of the inspection runs and by reducing the number of manual inspections needed by an inspector. The method is also advantageous because it reduces duplication of work (by an inspector). This is done by reducing the times the inspector needs to take a look at a defect which was already inspected in a previous run and where the defect did not change in between the (successive) various runs. To be able to obtain this advantage, it is important to save information of successive runs. For this purpose, the method according to the invention includes the step of identifying a roll, such that information on that specific roll can be stored. Which means that in a recursive inspection run process, the inspection for the initial run will be similar as to the methods used currently. It is in particular when performing successive inspection runs that the method according to the present invention is advantageous. If defects are detected during the initial run the inspector can determine, based on the determined amplitude and optionally a manual inspection, if the roll should be rejected. If rejection is the outcome of the (manual) inspection no successive runs will follow. The inspector may also determine, based on the determined amplitude and optionally a manual inspection, that the detected defect is allowable and the roll can continue to be used in operation. In the latter case the inspector can set a local threshold value which is automatically taken into account for the next run if the method according to the present invention is used.
The inspector referred to in this document may be an actual person or an automated robot or the like.
The method enables an inspector to set a specific threshold value for an inspected defect, which defect was found to be allowable. In the currently known procedures the inspector has to inspect the defect in each run where the signal as detected by the inspection element has an amplitude which is higher than the initial general threshold value. It is important that for each detected defect the inspector can set a location specific threshold, so that the inspector can take into account other circumstances that apply to that specific location where the defect is detected.
Other circumstances may for example be other nearby defects, material of the roll, application of the roll, location of the defect with respect to the surface of the roll, or the time over which the defect occurred.
For the next inspection run, the inspector is not called upon if the amplitude exceeds the initial threshold value but falls below the local threshold value, which would have been the case in the currently known methods. As such, the method is advantageous because use of the method according to the present invention prevents costs for unnecessary inspections by an inspector (multiple recursive inspections on the same location of the roll while the defect in that location is allowable).
Due to setting a local threshold the lead time of the inspection can be speed up significantly since not all defects need to be manually inspected by an inspector.
Which means in practice that less rolls will be in on hold waiting for manual inspection in order to be either accepted or rejected, which is very advantageous considering efficiency, labour and costs.
The method according to the invention in particular relates to mill rolls, preferably 5 cast and/or forged rolls. It is also possible that the method according to the present invention is used for inspection of Continuous Poured Casting (CPC) rolls, and/or
Surface Cladded rolls (SCR). The method makes use of an inspection station comprising at least one receiving space, preferably a receiving space wherein the at least one roll can be rotatably received. The ability to rotate the roll is advantageous for the inspection runs. The inspection station further comprises at least one inspection element, typically comprising at least one transmitter and at least one receiver. The at least one inspection element comprises at least one receiver and at least one transmitter. It is conceivable that at least one inspection element comprises at least one transceiver element. However, it is also conceivable that at least one receiver and at least one transmitter as separate elements. Further the inspection station comprises at least one control unit directly or indirectly connected with at least one inspection element and configured to determine an amplitude of the reflected signal per location of the mantle of the roll.
Said amplitude is used by the method to determine the quality of (a location on) the roll
The steps of the method will be explained further below.
Step A) positioning of a roll to be inspected in the receiving space of the inspection station is advantageous for knowing the relative locations on the roll. This contributes to the ease of running an inspection run. The more precise a roll is positioned, the better. Step B) of identifying the roll also contributes to the ease of running an inspection run. In step C) an initial threshold value is determined. The initial threshold value can be a threshold value as set by the manufacturer or another standard in case of an initial run. To be able to retrieve this data in successive runs this is stored in a database, wherein the threshold value is linked to the identity of the roll. In a successive run it is possible that there is a local threshold value for a specific location on the (mantle of the) roll, this is then retrieved from the database and used during the inspection run. There may be several local threshold values for an identified roll.
In the step of scanning the quality of the material, the quality of the material is defined by present so-called defects. Examples of defects are surface defects cracks, bruises or hardness and/or structural changes and subsurface defects such as cracks, inclusions, hardness and/or structural changes, spalls, debonding defects. Depending on the technology used for the inspection elements these defects may be detected by the inspection elements during the inspection. It is up to the user of the method to select a suitable inspection element. An inspection element comprises at least one transmitter and at least one receiver wherein the signal received by the receiver has an amplitude. Said amplitude is determined in step E). Some examples of suitable inspection elements are given later.
During step F) from the method according to the present invention the determined amplitude of a reflected signal is compared with a predetermined threshold value, being the initial threshold value or a local threshold value. The amplitude is coupled to the location on the roll from where the signal was reflected. The predetermined threshold value may be an initial threshold value which was set by the manufacturer for example. The predetermined threshold value may also be a stored local threshold value for the specific location corresponding to the area or location where the signal was from. The local threshold value usually is a result from a previous inspection run in operation or from a first inspection run at the manufacturer. The threshold value, both initial threshold value or local threshold value, may be set such that an inspection is needed upon reaching the threshold value by the amplitude or upon exceeding the threshold value by the amplitude. If the amplitude falls within the threshold value, the quality of the roll is good enough for the roll to continue in operation, for example hot rolling operations for rolling steel. if the amplitude does not fall within the threshold value, there is an incentive for additional inspection of the specific location of the roll. This inspection can result in rejection of the roll if the quality (or defect) is such that safe operation is no longer possible. It is also possible that this inspection results in setting a new specific local threshold value for that specific location, where a safe operation is still possible given the specific circumstances of the inspected quality (defect).
The method is particularly advantageous for multiple recursive inspection runs.
Steps A-F of the method are then applied to an (identified) roll multiple times, wherein alternately the roll is used in a manufacturing process and is inspected by the method according to the invention.
Another application wherein the method according to the invention may be used is after production of a roll, in particular a mill roll. If this is the case, the data stored in the initial run is then used in the next inspection run. In this application a first inspection run at an operational site is then a successive inspection run and not the initial run.
The method according to the present invention can be used for the inspection of various types of rolls (cast, forged, CPC rolls or SCR). However, the method is in particular advantageous for cast rolls, because in cast rolls there is a fused layer or transition zone where debonding can occur. The transition zone is also called the debonding zone. The fused layer, bonding zone or transition zone, is the layer or zone where the mantle of the roll is cast onto the core of the roll. Where the mantle is bonded onto the core. It is advantageous that using the method according to the present invention debonding defects are detected and their severeness can be identified.
As said various inspection elements may be used, depending on the application or the users’ preference. In a preferred embodiment of the method according to the present invention, the transmitter is an ultrasonic transmitter and the receiver is an ultrasonic receiver. Ultrasonic technology is in particular advantageous to detect internal cracks, mechanical and manufacturing defects, inclusions and debonding (in case of cast rolls) in the roll.
In an embodiment of the method according to the present invention, during step B) the data regarding the identity of the roll is stored in the database. This makes it easier for the next run to quickly get all data with respect to the specific roll available. The identity of the roll can comprise a unique roll number, type number or code name for the roll.
The mantle of a roll typically has a cylindrical shape and as such either the at least one inspection element moves around the roll or the roll will rotate to present its entire surface to the at least one inspection element. lt is preferred that the rol! rotates during scanning in step D). The rotating movement of the roll enables the atleast one inspection element(s) to move linearly along the length and/or width of the roll and due to the combined movement with the rotating roll all locations of the roll can be inspected. It is easier to let the inspection elements move linearly instead of around the roll and thus it is advantageous for the roll to rotate during scanning to present all locations to the inspection elements.
The inspection elements scan the outside surface of the mantle of the roll to be inspected. The mantle of the roll typically forms an inspection layer and the at least one inspection element is configured to scan said inspection layer. Optionally, the inspection layer may comprise the subsurface of the mantle of the roll, up to a depth of 6 mm from the surface of the roll. The inspection elements still inspect the surface, but the signal it sends and/or receives may be able to inspect a subsurface layer of the roll. In an alternative embodiment, the inspection element inspects an inspection layer, which inspection layer is the fused layer of the mantle of the roll with the cast core. The fused layer is a sensitive layer of the roll and as such it is advantageous to be able to inspect this specific layer for quality and/or defects. The fused layer typically is a layer which is located in a transition zone or bonding zone of a cast roll. For cast rolls it is preferred that the transition zone, or bonding zone can be inspected. The inspection layer is then the transition or bonding zone. The transition zone, or bonding zone is typically located at a depth (measured from the surface of the roll) which measures about 10% from the diameter of the roll at the beginning of the lifetime. Over time this decreases. In an embodiment of the method according to the present invention, at least one inspection element may be configured to detect defects up to at least 125 mm, or more preferably up to at least 200 mm, even more preferably up to at least 280 mm. This is advantageous for inspecting the transition or bonding zone of a cast roll.
In a simple embodiment of the method according to the present invention the threshold value is a single threshold value. The threshold value is exceeded if the any value from the amplitude exceeds the single threshold value. This is an effective way to filter which locations should receive further inspection. Most defects can be located by using a single value threshold value. In this embodiment the initial threshold value may have a different single threshold value than the single threshold value of the local threshold value.
In another embodiment it is possible to monitor more complex defects or quality aspects of the material of the roll to be inspected. For example, if a defect is only a danger for safe operation if the defect (e.g. a crack) exceeds a certain length. Then, it is useful to only exceed the threshold value upon exceeding the certain length and as such a threshold pattern would be advantageous. In this embodiment, the threshold value is defined by a threshold pattern, in particular such that the amplitude of the signal must exceed the threshold over said threshold pattern at least multiple times (for exceeding the threshold value). It could also mean that multiple signals are necessary to determine if the threshold value formed by the threshold pattern is exceeded. For example, the threshold value may be defined by athreshold pattern, in particular such that the amplitudes of the reflected signals exceed the threshold values in said threshold pattern at least multiple times.
Preferably the multiple times is defined as a predefined number of times.
To set a local threshold value it is advantageous to define the location area. In an embodiment of the method according to the present invention, a location may be identified for the location specific local threshold value as a rectangular area upon the mantle surface. The location may be defined during step F and consequently stored in the database. Within the defined rectangular area the local threshold value overwrites the initial general threshold value. The identified location may be a relative location relative to the side edges of the roll or the like.
Since defects tend to not be squared or rectangular, it is advantageous if the shape of the defect can be followed better during the inspection runs. To this end, a location may be identified for the location specific local threshold value as a freely defined form. Said freely defined form may be for example with its circumference at a predetermined distance from the circumference of the detected defect. It is for example conceivable that the freely defined form has a circumference of at least 1 mm from the circumference of the detected defect, possibly at least 1.5 mm or at least 2 mm. In this embodiment there is a very specific and local approach possible to set a local threshold value for a specific region. This ensures a safer operation because a defect can be monitored very precisely.
In an embodiment of the method according to the present invention, the control unit is configured to determine the depth and/or size and/or nature of a defect using the amplitude of the reflected signal. For example indicating that a crack is detected or that a defect is getting more severe quickly. This is advantageous because it would enable a possibility for a quicker inspection of the roll in step F of the method according to the present invention. The additional information provided by the control unit may provide an indication of the risk level of the detected defect.
For the inspection and scanning steps various technologies are possible to implement in the method according to the present invention. Preferably, the inspection elements comprise at least one transmitter using a technology chosen out of the group consisting of: eddy current, ultrasonic wave technology, micro magnetic analysis and/or ultrasonic technology. Depending on the application of the roll or the goal of the inspection run the technology may be chosen by the user.
The eddy current technology is advantageous for the detection of small cracks.
Wave technology is advantageous to detect cracks on and beyond the surface up to a depth of 5 mm from the surface and ultrasonic technology is advantageous to detect surface defects in cast and/or forged rolls. Micro magnetic analysis can be used for contactless hardness measurement.
Detects typically occur at the surface of the (mantle of the) roll where the roll is in contact with other materials. In an embodiment at least one inspection element is configured to detect defects at a depth of 0 mm. The depth is measured from the outer cylindrical surface towards the rotary axis of the roll. However, defects may occur (slightly) below the surface within the material of the (mantle of the) roll.
Therefore the at least one inspection element may be configured to detect defects at the surface and/or subsurface of the mantle of the roll.. It is also conceivable that defects occur in the transition zone, or debonding zone. To detect these kind of defects it is advantageous when the at least one inspection elements are configured to detect defects in the transition zone, in particular up to a depth of 125 mm, preferably up to a depth of 200 mm, even more preferably up to a depth of 280 mm. Most preferably the inspection element is configured to detect defects up to a depth of 10% of the diameter of the roll. Said depth measured from the outer surface of the roll.
During operation the rolls are subject to wear and defects are expected to occur due to the use of the roll in operation. These small defects at the surface tend to grow further. For this reason, it is possible to grind the surface of the roll prior to inspection. Grinding increases the quality of the surface of the rol! and may prevent small cracks on the surface to grow further. For this purpose, the method according to the present invention may comprise the step of grinding the surface of the roll to be inspected prior to scanning in step D), preferably wherein grinding and scanning takes place in the same inspection station. It is possible to perform the grinding and scanning within the same receiving space. This is advantageous for a quick lead time for the entire process and saves complicated movements of the roll to be inspected (and optionally grinded). Alternatively, the roll is transported in between a grinding step and the scanning step.
Step F sub b), determining the difference of the value of the amplitude with the initial or stored threshold values, may be done manually and/or by an automated inspection unit. A manual inspection may be performed by an inspector, or a supervisor. The advantage of manual inspection is that a wide variety of measures can be taken into account and also the combination of locations where defects or quality decrease occurred can be taken into account by the inspector. An automated inspection unit is advantageous because it is very quick and saves time, but it can only take into account the information that it is fed with upfront.
The invention further relates to an inspection station for recursive inspection of rolls, in particular mill rolls, preferably to perform the method according to the invention comprising at least one receiving space for receiving at least one roll, in particular mill roll, which is to be inspected; at least one inspection element comprising at least one transmitter and at least one receiver, wherein the transmitter is configured to send at least one signal ‚in particular an ultrasonic signal, to the surface and/or subsurface of the mantle of the roll and/or transition zone in the roll, and wherein the receiver is configured to receive at least part of a signal reflected by said surface and/or subsurface of the mantle of the roll and/or transition zone; at least one control unit connected with at least one inspection element and configured to determine an amplitude of the reflected signal per location of the mantle of the roll; and at least one database for storing data of each performed inspection run. For example, the database may be configured for storing the determined amplitudes per location, such that they can be compared with the (local) threshold values.
In an embodiment, the inspection station is further provided with at least one grinding element for grinding the roll prior to inspection. As mentioned above, grinding can prevent small defects at the surface to grow further by removing the defect by grinding the surface of the roll by the grinding element.
It is preferred that the inspection station comprises a spinning box comprising the receiving space, such that the roll can rotate within the receiving space. As mentioned above, this is advantageous to effectively reach each location of the mantle of the roll by at least one inspection element. The inspection element may move linearly, preferably horizontally along the width (or length) of the roll.
The invention is further elucidated by the following non-limitative exemplary figures, wherein: - Figure 1 shows a schematic flowchart of an embodiment of the method according to the present invention; - Figure 2 shows an embodiment of a display of an inspection station according to the present invention; and - Figure 3 shows a schematic view of an embodiment of an inspection station/Inspection station according to the present invention; and - Figure 4 shows a schematic view of a cross-section of a milling roll.
Figure 1 shows a schematic flowchart of an embodiment of the method according to the present invention. The flowchart shows the schematic flow for a method for recursive inspection of rolls, in particular mill rolls, wherein each roll comprises a substantially cylindrical mantle, wherein the method makes use of an inspection station (for example like shown in figure 3), said inspection station comprising: at least one receiving space for receiving at least one roll, in particular mill roll, which is to be inspected and at least one inspection element comprising at least one transmitter and at least one receiver, wherein the transmitter is configured to send at least one signal to the surface of the mantle of the roll, and wherein the receiver is configured to receive at least part of a signal reflected by said surface of the mantle of the roll. Further comprising at least one control unit connected with at least one inspection element and configured to determine an amplitude of the reflected signal per location of the mantle of the roll; and at least one database for storing data of each performed inspection run. The database is suitable for storing the determined amplitudes per location. The figure shows a flowchart representing the method performed in each inspection run comprising the steps of:
A. positioning a roll to be inspected in the receiving space of the inspection station;
B. identifying the rolf;
C. a. determining an initial threshold value for an allowable amplitude of reflected signals for each location of the mantle of the identified roll and storing this threshold value in the database and/or b. loading from the database local threshold values for an allowable amplitude of reflected signals for each location of the mantle of the identified roll from the previous inspection run as stored in the database;
D. scanning the quality of the material of at least part of the mantle, preferably substantially entire mantle, of the roll by the inspection element via transmitting at least one signal from the transmitter to the surface of the mantle of the roll, and receiving at least part of a reflected signal from the transmitted signal, wherein the reflected signal is reflected by the surface and/or subsurface of the mantle of the roll and/or by the transition zone in the roll;
E. determining the amplitude of at least one signal reflected during step
D of at least one location of the mantle of the roll;
F. comparing the determined amplitude per location with the stored initial threshold values and/or stored local threshold values per location of the mantle of the roll, and: a. allowing the roll to be released for operation in case the determined amplitude per location falls within the stored threshold value for that location; orb. determine the difference with the initial threshold value and/or stored local threshold values in case the determined amplitude of at least one location exceeds the stored initial threshold value or local threshold value and based upon the determined difference and/or based upon the location of the exceeded threshold value on the mantle, either: i. determine a local threshold value for at least one location and overwrite the stored initial threshold value or previous local threshold value by said new local threshold value to an allowable amplitude for the specific location of the mantle of the roll and store the new local threshold value in the database; or ii. reject the roll.
After allowing the roll to continue to be in operation, after step F-a and F-b-i, the roll will be used in operation again. The recursive way and operation step O is shown in the figure with dashed lines.
Figure 2 shows an embodiment of a user interface of a display 21 of a Inspection station according to the present invention. The user interface shows the results of an inspection run of a roll wherein two defects 22, 23 are detected. In the shown embodiment the defects are shown as rectangles. The location of the defects is identified by dashed lines. In the shown embodiment the location of the defects 22,23 are identified by a rectangular area 24, 25. For the defined rectangular area 24, 25 a location specific local threshold value is defined by the inspector. The location specific local threshold value is then set for those areas as input for the next inspection run. On the X-axis the corresponding location on the roll is presented in millimetres. The Y-axis also represents millimetres. This enables the inspector to find the actual location of the defects on the roll. In the user interface it is possible to show the status of the roll in a text field 26, for example by showing ‘roll released’ or ‘roll blocked’. Preferably also enforced by either green or red colours respectively.
Figure 3 shows an embodiment of an inspection station according to the present invention. The embodiment shown can be applied in the method according to the present invention, and for example as referred to in figure 1. The Inspection station 30 comprises at least one receiving space 31 for receiving at least one roll 32, in particular mill roll, which is to be inspected. The Inspection station further comprises at least one inspection element 33 comprising at least one transmitter 33a and at least one receiver 33b, wherein the transmitter is configured to send at least one signal (in particular an ultrasonic signal) to the surface (and/or subsurface) of the mantle of the roll, and wherein the receiver is configured to receive at least part of a signal reflected by said surface 34 (and/or subsurface) of the mantle of the roll 32.
The transmitter and receiver 33b are connected to the control unit 36, which is located in proximity to the receiving space 31. The control unit 36 is configured to determine an amplitude of the reflected signal per location of the mantle of the roll 32. Said amplitude is compared to predetermined threshold values to determine whether or not the roll should be rejected or released during inspection. The data from the inspection run are stored in a database 37. The data may include amplitudes, initial and local threshold values, identification codes of the roll, inspection history and the like.
Figure 4 shows two schematic views of a cross-section of a milling roll. The figure shows a cross section of a cast roll in figure 4a and a forged roll in figure 4b. both rolls have a substantially cylindrical outer surface. The cast roll 40 shown, comprises a mantle 41, a core 42 and a transition zone or fused layer 43 in between the core and the mantle of the rol! 40. Typically, the width A of the mantle of the roll is about ten percent of the diameter D of the roll, at the beginning of the lifetime of the roll. The mantle of the roll will wear during operation and the respective width of the mantle of the roll with respect to the total diameter will decrease. The outer substantially cylindrical outer surface 44 of the cast roll will decrease in diameter over use as well. The figure also shows a cross section of a forged roll 45, wherein no transition zone or fused layer is present. The rol! comprises a substantially cylindrical outer surface 46. The substantially cylindrical outer surface 46 of the roll will decrease in diameter during its lifetime. it will be clear that the invention is not limited to the exemplary embodiments which are illustrated and described here, but that countless variants are possible within the framework of the attached claims, which will be obvious to the person skilled in the art. In this case, it is conceivable for different inventive concepts and/or technical measures of the above-described variant embodiments to be completely or partly combined without departing from the inventive idea described in the attached claims.
The wording mantle of the roll as used in this patent document is understood to mean not only ‘mantle of the roll’, but to also include the surface and subsurface of the roll.
The verb ‘comprise’ and its conjugations as used in this patent document are understood to mean not only ‘comprise’, but to also include the expressions ‘contain’, ‘substantially contain’, "formed by' and conjugations thereof. When it is referred to an inspection station, also an inspection system can be meant.

Claims (18)

ConclusiesConclusions 1. Werkwijze voor recursieve inspectie van rollen, in het bijzonder walsen, waarbij iedere rol een in hoofdzaak cilindrisch buitenoppervlak omvat, waarbij de werkwijze gebruikmaakt van een inspectiestation, voornoemd inspectiestation omvat: e ten minste één ontvangstruimte voor het ontvangen van ten minste één rol, in het bijzonder wals, die geïnspecteerd dient te worden; e ten minste één inspectie-element omvattende ten minste één zender en ten minste één ontvanger, waarbij de zender is ingericht om ten minste één signaal te zenden naar het oppervlak en/of sub-oppervlak van de mantel van de rol en/of naar een overgangsgebied, en waarbij de ontvanger is ingericht om ten minste een deel van een signaal te ontvangen dat wordt gereflecteerd door voornoemd oppervlak en/of sub-oppervlak van de mantel van de rol en/of een overgangsgebied; e ten minste één besturingseenheid verbonden met ten minste één inspectie- element en ingericht om een amplitude te bepalen van het gereflecteerde signaal per locatie en/of sub-oppervlak van de mantel van de rol en/of een overgangsgebied; en e ten minste één database voor het opslaan van data van iedere uitgevoerde inspectieronde; de werkwijze uitgevoerd in iedere inspectieronde omvattende de stappen van:1. Method for recursive inspection of rolls, in particular rolls, wherein each roll comprises a substantially cylindrical outer surface, the method using an inspection station, said inspection station comprising: e at least one receiving area for receiving at least one roll, in particular roller, which needs to be inspected; e at least one inspection element comprising at least one transmitter and at least one receiver, wherein the transmitter is designed to transmit at least one signal to the surface and/or sub-surface of the shell of the roller and/or to a transition area, and wherein the receiver is arranged to receive at least part of a signal reflected by said surface and/or sub-surface of the roller shell and/or a transition area; e at least one control unit connected to at least one inspection element and arranged to determine an amplitude of the reflected signal per location and/or sub-surface of the roller shell and/or a transition area; and e at least one database for storing data from each inspection round carried out; the method carried out in each inspection round, including the steps of: A. het plaatsen van een rol die geïnspecteerd dient te worden in de ontvangstruimte van het inspectiestation;A. placing a roll to be inspected in the reception area of the inspection station; B. het identificeren van de rol;B. identifying the role; C. a. het bepalen van een initiële drempelwaarde voor een aanvaardbare amplitude van gereflecteerde signalen voor iedere locatie van de mantel van de geïdentificeerde rol en het opslaan van deze drempelwaarde in de database en/of b. het laden van lokale drempelwaarden uit de database voor een aanvaardbare amplitude van gereflecteerde signalen voor iedere locatie van de mantel van de geïdentificeerde rol van de vorige inspectieronde zoals opgeslagen in de database;C. a. determining an initial threshold value for an acceptable amplitude of reflected signals for each location of the jacket of the identified roll and storing this threshold value in the database and/or b. loading local thresholds from the database for an acceptable amplitude of reflected signals for each location of the shroud of the identified roll from the previous inspection round as stored in the database; D. het scannen van de kwaliteit van het materiaal van ten minste een deel van de mantel, bij voorkeur in hoofdzaak gehele mantel, van de rol door het inspectie-D. scanning the quality of the material of at least part of the jacket, preferably substantially the entire jacket, of the roll by the inspection element door het verzenden van ten minste één signaal van de zender naar het oppervlak van de mantel van de rol, en het ontvangen van ten minste een deel van een gereflecteerd signaal van het verzonden signaal, waarbij het gereflecteerde signaal wordt gereflecteerd door het oppervlak en/of sub-oppervlak van de mantel van de rol en/of door het overgangsgebied in de rol;element by transmitting at least one signal from the transmitter to the surface of the roller shell, and receiving at least a portion of a reflected signal from the transmitted signal, the reflected signal being reflected by the surface and/ or sub-surface of the roller shell and/or through the transition region in the roller; E. het bepalen van de amplitude van ten minste één signaal dat gereflecteerd wordt tijdens stap D van ten minste één locatie van de mantel van de rol;E. determining the amplitude of at least one signal reflected during step D from at least one location of the roller shell; F. het vergelijken van de bepaalde amplitude per locatie met de opgeslagen initiële drempelwaarden en/of opgeslagen lokale drempelwaarden per locatie van de mantel van de rol, en:F. comparing the determined amplitude per location with the stored initial threshold values and/or stored local threshold values per location of the roller shell, and: a. het toestaan van de rol om vrijgegeven te worden voor gebruik in het geval de bepaalde amplitude per locatie binnen de opgeslagen drempelwaarde voor die locatie valt; or b. het bepalen van het verschil met de initiële drempelwaarde en/of opgeslagen lokale drempelwaarden in het geval de bepaalde amplitude van ten minste één locatie de opgeslagen initiële drempelwaarde of lokale drempelwaarde overschrijdt en gebaseerd op het bepaalde verschil en/of gebaseerd op de locatie van de overschreden drempelwaarde op de mantel, ofwel:a. allowing the role to be released for use in the event that the determined amplitude per location falls within the stored threshold for that location; or b. determining the difference with the initial threshold value and/or stored local threshold values in case the determined amplitude of at least one location exceeds the stored initial threshold value or local threshold value and based on the determined difference and/or based on the location of the exceeded threshold value on the mantle, or: i. bepaal een lokale drempelwaarde voor ten minste één locatie en overschrijf de opgeslagen initiële drempelwaarde of vorige lokale drempelwaarde door voornoemde nieuwe lokale drempelwaarde tot een aanvaardbare amplitude voor de specifieke locatie van de mantel van de rol en sla de nieuwe lokale drempelwaarde op in de database; of ii. keur de rol af.i. determine a local threshold value for at least one location and overwrite the stored initial threshold value or previous local threshold value with said new local threshold value to an acceptable amplitude for the specific location of the roller shell and store the new local threshold value in the database; or ii. reject the role. 2. Werkwijze volgens conclusie 1, waarbij ten minste één zender een ultrasone zender is en/of waarbij ten minste één ontvanger een ultrasone ontvanger is.Method according to claim 1, wherein at least one transmitter is an ultrasonic transmitter and/or wherein at least one receiver is an ultrasonic receiver. 3. Werkwijze volgens één der voorgaande conclusies, waarbij tijdens stap B) de data betreffende de identiteit van de rol wordt opgeslagen in de database.3. Method according to any of the preceding claims, wherein during step B) the data regarding the identity of the role is stored in the database. 4. Werkwijze volgens één der voorgaande conclusies, waarbij de rol roteert gedurende het scannen in stap D}.4. Method according to any one of the preceding claims, wherein the roller rotates during scanning in step D}. 5. Werkwijze volgens één der voorgaande conclusies, waarbij de mantel van de rol een inspectielaag vormt en het inspectie-element is ingericht om voornoemde inspectielaag te scannen.5. Method according to any one of the preceding claims, wherein the jacket of the roller forms an inspection layer and the inspection element is designed to scan said inspection layer. 6. Werkwijze volgens één der voorgaande conclusies, waarbij het inspectie- element een inspectielaag inspecteert, welke inspectielaag de versmolten laag van de mantel van de rol met de gegoten kern is.Method according to any one of the preceding claims, wherein the inspection element inspects an inspection layer, which inspection layer is the fused layer of the jacket of the roll with the cast core. 7. Werkwijze volgens één der voorgaande conclusies, waarbij ten minste één drempelwaarde een enkele drempelwaarde is.Method according to any one of the preceding claims, wherein at least one threshold value is a single threshold value. 8. Werkwijze volgens één der voorgaande conclusies, waarbij ten minste één drempelwaarde gedefinieerd wordt door een drempelpatroon, in het bijzonder zodanig dat voor het overschrijden van de drempelwaarde de amplituden van gereflecteerde signalen de drempelwaarden in het voornoemde drempelpatroon ten minste meerde malen moet overschrijden.Method according to any one of the preceding claims, wherein at least one threshold value is defined by a threshold pattern, in particular such that to exceed the threshold value the amplitudes of reflected signals must exceed the threshold values in the aforementioned threshold pattern at least several times. 9. Werkwijze volgens één der voorgaande conclusies, waarbij een locatie wordt geïdentificeerd voor de locatie specifieke drempelwaarde als een vrij gedefinieerde vorm, in het bijzonder het volgen van de contour van een gedetecteerde afwijking.Method according to any one of the preceding claims, wherein a location is identified for the location-specific threshold value as a freely defined shape, in particular following the contour of a detected deviation. 10. Werkwijze volgens één der voorgaande conclusies, waarbij ten minste één locatie wordt geïdentificeerd voor de locatie specifieke drempelwaarde als een gebied met een voorafbepaalde vorm op het manteloppervlak van de rol, bijvoorbeeld een rechthoekvormig gebied op het mantelopperviak.Method according to any one of the preceding claims, wherein at least one location is identified for the location-specific threshold value as an area with a predetermined shape on the lateral surface of the roll, for example a rectangular area on the lateral surface. 11. Werkwijze volgens één der voorgaande conclusies, waarbij de besturingseenheid is ingericht om de diepte en/of grootte en/of aard van een gebrek te bepalen gebruikmakend van de amplitude van het gereflecteerde signaal.11. Method according to any one of the preceding claims, wherein the control unit is designed to determine the depth and/or size and/or nature of a defect using the amplitude of the reflected signal. 12. Werkwijze volgens één der voorgaande conclusies, waarbij het inspectie- element ten minste één zender omvat gebruikmakend van een technologie gekozen uit de groep bestaande uit: wervelstroom, ultrasone oppervlaktegolftechnologie, micro magnetische analyse en/of ultrasone technologie.Method according to any one of the preceding claims, wherein the inspection element comprises at least one transmitter using a technology selected from the group consisting of: eddy current, ultrasonic surface wave technology, micro magnetic analysis and/or ultrasonic technology. 13. Werkwijze volgens één der voorgaande conclusies, waarbij ten minste één inspectie-element ingericht is om gebreken te detecteren op een diepte van 0 mm, waarbij de diepte wordt gemeten van het cilindrische buitenoppervlak naar de rotatie as van de rol.Method according to any one of the preceding claims, wherein at least one inspection element is arranged to detect defects at a depth of 0 mm, wherein the depth is measured from the cylindrical outer surface to the rotation axis of the roller. 14. Werkwijze volgens één der voorgaande conclusies, waarbij ten minste één inspectie-element is ingericht om gebreken te detecteren tot ten minste 125 mm, of meer bij voorkeur tot ten minste 200 mm, bij nog meer voorkeur tot ten minste 280 mm.Method according to any one of the preceding claims, wherein at least one inspection element is designed to detect defects up to at least 125 mm, or more preferably up to at least 200 mm, even more preferably up to at least 280 mm. 15. Werkwijze volgens één der voorgaande conclusies, waarbij de werkwijze de stap van het slijpen van het oppervlak van de mantel van de rol dat geïnspecteerd dient te worden omvat voor het scannen in stap D}, bij voorkeur waarbij het slijpen en het scannen in hetzelfde inspectiestation plaatsvindt.Method according to any one of the preceding claims, wherein the method comprises the step of grinding the surface of the roller jacket to be inspected before scanning in step D}, preferably wherein the grinding and scanning are carried out in the same inspection station takes place. 16. Werkwijze volgens één der voorgaande conclusies, waarbij stap F sub b) handmatig wordt gedaan en/of door een geautomatiseerde keuringseenheid.16. Method according to any of the preceding claims, wherein step F sub b) is done manually and/or by an automated inspection unit. 17. Inspectiestation voor het recursief keuren van rollen, in het bijzonder walsen, bij voorkeur voor het uitvoeren van de werkwijze volgens conclusie 1-16, omvattende:17. Inspection station for recursively inspecting rolls, in particular rollers, preferably for carrying out the method according to claims 1-16, comprising: a. ten minste één ontvangstruimte voor het ontvangen van ten minste één rol, in het bijzonder wals, die geïnspecteerd dient te worden;a. at least one reception area for receiving at least one roller, in particular roller, that needs to be inspected; b. ten minste één inspectie-element omvattende ten minste één zender en ten minste één ontvanger, waarbij de zender is ingericht om ten minste één signaal te versturen, in het bijzonder een ultrasoon signaal, naar het oppervlak en/of sub-oppervlak van de mantel en/of overgangsgebied van de rol, en waarbij de ontvanger is ingericht om ten minste een deel van een signaal gereflecteerd door voornoemd oppervlak en/of sub-oppervlak van de mantel en/of overgangsgebied van de rol te ontvangen;b. at least one inspection element comprising at least one transmitter and at least one receiver, wherein the transmitter is designed to send at least one signal, in particular an ultrasonic signal, to the surface and/or sub-surface of the casing and /or transition area of the roller, and wherein the receiver is arranged to receive at least part of a signal reflected by said surface and/or sub-surface of the jacket and/or transition area of the roller; c. ten minste één besturingseenheid verbonden met ten minste één inspectie- element en ingericht om een amplitude van het gereflecteerde signaal per locatie van de mantel van de rol te bepalen; en d. ten minste één database voor het opslaan van data voor iedere uitgevoerde inspectieronde.c. at least one control unit connected to at least one inspection element and arranged to determine an amplitude of the reflected signal per location of the roller shell; and d. at least one database for storing data for each inspection round carried out. 18. Inspectiestation volgens conclusie 17, voorzien van ten minste één slijpingselement voor het slijpen van ten minste een deel van het oppervlak van de mantel van een rol.18. Inspection station according to claim 17, provided with at least one grinding element for grinding at least part of the surface of the jacket of a roller.
NL2032520A 2022-07-18 2022-07-18 Method and inspection station for recursive inspection of rolls NL2032520B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
NL2032520A NL2032520B1 (en) 2022-07-18 2022-07-18 Method and inspection station for recursive inspection of rolls

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL2032520A NL2032520B1 (en) 2022-07-18 2022-07-18 Method and inspection station for recursive inspection of rolls

Publications (1)

Publication Number Publication Date
NL2032520B1 true NL2032520B1 (en) 2024-01-26

Family

ID=83506573

Family Applications (1)

Application Number Title Priority Date Filing Date
NL2032520A NL2032520B1 (en) 2022-07-18 2022-07-18 Method and inspection station for recursive inspection of rolls

Country Status (1)

Country Link
NL (1) NL2032520B1 (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4495587A (en) * 1981-12-08 1985-01-22 Bethlehem Steel Corporation Automatic nondestructive roll defect inspection system
US4754148A (en) * 1986-12-10 1988-06-28 Allegheny Ludlum Corporation Adjustably positioned apparatus maintaining a fixed perpendicular distance for evaluating a curved surface
US5469743A (en) * 1993-06-24 1995-11-28 Zorn; Roger H. Dynamic surface wave roll inspection device
US6625515B2 (en) * 2000-12-21 2003-09-23 Dofasco Inc. Roll defect management process
EP1447661A1 (en) * 2002-12-24 2004-08-18 Innerspec Technologies, Inc. Creeping wave technique for mill roll inspection
US20060203229A1 (en) * 2005-02-28 2006-09-14 Fuji Photo Film Co., Ltd. Method and apparatus for inspecting defect in surface of metal roll
DE102006028364A1 (en) * 2006-06-19 2007-12-27 Aluminium Norf Gmbh Method and device for condition monitoring of rolls

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4495587A (en) * 1981-12-08 1985-01-22 Bethlehem Steel Corporation Automatic nondestructive roll defect inspection system
US4754148A (en) * 1986-12-10 1988-06-28 Allegheny Ludlum Corporation Adjustably positioned apparatus maintaining a fixed perpendicular distance for evaluating a curved surface
US5469743A (en) * 1993-06-24 1995-11-28 Zorn; Roger H. Dynamic surface wave roll inspection device
US6625515B2 (en) * 2000-12-21 2003-09-23 Dofasco Inc. Roll defect management process
EP1447661A1 (en) * 2002-12-24 2004-08-18 Innerspec Technologies, Inc. Creeping wave technique for mill roll inspection
US20060203229A1 (en) * 2005-02-28 2006-09-14 Fuji Photo Film Co., Ltd. Method and apparatus for inspecting defect in surface of metal roll
DE102006028364A1 (en) * 2006-06-19 2007-12-27 Aluminium Norf Gmbh Method and device for condition monitoring of rolls

Similar Documents

Publication Publication Date Title
EP1350094B1 (en) Inspection and disposition of mill rolls
CN100390534C (en) Bearing steel, method for evaluating large-sized inclusions in the steel, and rolling bearing
NL2032520B1 (en) Method and inspection station for recursive inspection of rolls
US20040149295A1 (en) Wear indicator for a roller
CN100578213C (en) Fault detection method of roller body chamfering
WO2009142211A1 (en) Method of diagnosing roll
CN101153861A (en) Method for evaluating large-sized inclusions in the steel for rolling bearing
JP3748228B2 (en) Method for judging harmful defect in ultrasonic flaw detection and method for using the judgment result
CN111465845B (en) Method and device for inspecting rotary member
CN112067688A (en) Production process of bearing steel wire with undamaged surface
CN110646509B (en) Nondestructive testing method for cutting edge of hob ring of tunnel boring machine
JP4576726B2 (en) Flaw detection method and apparatus for roll for rolling metal plate, and rolling operation method for metal plate using the same
Palit Sagar et al. Surface wave based ultrasonic technique for finding the optimal grinding condition of high speed steel (HSS) work rolls
CN112945699B (en) Method for manufacturing comparison sample for heat damage eddy current inspection acceptance standard
JP3740959B2 (en) Equipment for cleaning surface of round steel materials
Chen et al. Using NDT methods for inspection work rolls
CN118549518A (en) Method for detecting soft points on surface of bearing/roller by combining weak magnetization and eddy current bidirectional scanning
EP4173752A1 (en) Machining device and method
Weinmeister et al. Improved mill roll inspection system
JPH05249051A (en) Detecting apparatus of imperfection of solvent of ingot bloom
Weinmeister et al. Improved technologies for mill roll inspection
KR20030050216A (en) Method for decreasing the amount of the surface defect by the roll mark in the hot roll process
JP6013216B2 (en) Method for manufacturing hollow tube material
CN102175765B (en) Method for detecting defects at shaft neck root or unloading slot part of belt conveyor drum shaft
Critchley et al. Roll grinding developments and relationships with production of tinplate and automotive sheet