{"id":21332,"date":"2026-10-08T13:27:20","date_gmt":"2026-10-08T05:27:20","guid":{"rendered":"https:\/\/aobosteel.com\/?page_id=21332"},"modified":"2026-10-08T13:27:20","modified_gmt":"2026-10-08T05:27:20","slug":"steel-bar-and-billet-inspection","status":"publish","type":"page","link":"https:\/\/aobosteel.com\/es\/steel-bar-and-billet-inspection\/","title":{"rendered":"C\u00f3mo se inspeccionan las barras y los tochos de acero para detectar defectos"},"content":{"rendered":"\n<style>\n\n:root{\n    --aobo-accent:#2563eb; --aobo-accent-dark:#1e1e2e; --aobo-blue:#0c56d0; --aobo-blue-dark:#073b91;\n    --aobo-text:#333; --aobo-muted:#888; --aobo-border:#e5e7eb; --aobo-border-dark:#ddd;\n    --aobo-stripe:#f7f7f9; --aobo-hover:#e8f0fe; --aobo-radius:8px; --aobo-radius-sm:6px;\n    --aobo-orange:#f59e0b; --aobo-fill:#e9ecef;\n  }\n  *{box-sizing:border-box;}\n  html{-webkit-text-size-adjust:100%;}\n  body{margin:0;background:#fff;color:var(--aobo-text);\n    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!important}.entry-content[class] h2{font-size: 25px !important}.entry-content[class] h3{font-size: 20px !important}.entry-content[class] h4{font-size: 17px !important}.entry-content[class] p,.entry-content[class] li{font-size: 16px !important}.entry-content[class] table th,.entry-content[class] table td{font-size: 14px !important;padding: 11px 12px !important}.entry-content[class] .aobo-hero{padding: 30px 22px}.entry-content[class] .aobo-final-cta{padding: 26px 22px}.entry-content[class] .aobo-final-cta .aobo-btn{width: 100%}}\n<\/style>\n<section class=\"aobo-ht-ref ts-props\">\n<div class=\"aobo-wrap\">\n\n<div class=\"ts-hero\">\n<div class=\"ts-hero-top\">\n<div class=\"ts-kicker\"><span><\/span>Tool Steel | Bar and Billet | Flaw Detection<\/div>\n<h1 style=\"--h1-max:38px\">How Steel Bar and Billet Are Inspected for Flaws<\/h1>\n<p>A tool steel bar reaches the buyer with a mill certificate and, on the larger sizes, a flaw detection report. The two halves of that package rest on very different methods, and the flaw report is the half most buyers understand least. This page sets out the four methods used on steel bars and billets, the flaw size each one can actually reach, and the two properties of bar inspection that decide what a report can and cannot promise.<\/p>\n<\/div>\n<\/div>\n\n<div class=\"ts-tool-area\">\n\n<h2 class=\"ts-h2\">Four methods cover a bar<\/h2>\n<p class=\"ts-p\">Almost all inspection of steel bars, beyond a plain visual pass, is done by one of four methods or by a combination of them. They are magnetic particle, liquid penetrant, ultrasonic and electromagnetic inspection. Each works from a different physical property, so each is blind to something the others see, and the choice on a given order follows the flaw that the order has to exclude.<\/p>\n<div class=\"ts-table-wrap\">\n<table class=\"ts-table\">\n<thead>\n<tr>\n<th style=\"width:16%\">Method<\/th>\n<th style=\"width:46%\">What it finds on a bar<\/th>\n<th>Practical limit<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr><td class=\"ts-grade\">Visual inspection<\/td><td class=\"ts-safe\">Surface condition, scale, seams visible to the eye, handling damage<\/td><td class=\"ts-safe\">Depends on the eye of the inspector and the judgement of severity<\/td><\/tr>\n<tr><td class=\"ts-grade\">Magnetic particle<\/td><td class=\"ts-safe\">Surface and near-surface seams, cracks, laps and slivers<\/td><td class=\"ts-safe\">Cannot reach flaws more than about 2.5 mm (0.1 in.) below the surface<\/td><\/tr>\n<tr><td class=\"ts-grade\">Liquid penetrant<\/td><td class=\"ts-safe\">Flaws that are open to the surface, including tight grinding and fatigue cracks<\/td><td class=\"ts-safe\">Surface breaking flaws only, and too slow for bar inspected in quantity<\/td><\/tr>\n<tr><td class=\"ts-grade\">Ultrasonic<\/td><td class=\"ts-safe\">Internal flaws, voids, inclusions and cracks in the body of the bar<\/td><td class=\"ts-safe\">Needs a liquid couplant and runs more slowly than an electromagnetic line<\/td><\/tr>\n<tr><td class=\"ts-grade\">Electromagnetic<\/td><td class=\"ts-safe\">Seams and cracks, and at the same time composition, hardness and structure<\/td><td class=\"ts-safe\">The method most widely used on bars, and the one that suits mass production<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"ts-tcap\"><em>The four methods used on steel bar, with what each one finds and the limit stated for it in the source article, reproduced from Nondestructive Inspection of Steel Bar, Wire and Billets in ASM Handbook, Volume 17. The industry also notes a further reason for inspecting bar at the bar stage, which is to remove unacceptable material before time and energy are spent machining a part that would fail later.<\/em><\/p>\n\n<h2 class=\"ts-h2\">Magnetic particle on bar<\/h2>\n<p class=\"ts-p\">Magnetic particle inspection puts a magnetic field into the bar and lets a flaw leak flux at the surface, where fine iron powder settles onto the leak and outlines the flaw. It finds seams, cracks and laps, and it reaches a short distance below the surface. As a rule the method cannot detect flaws more than 2.5 mm (0.1 in.) beneath the surface, and the leakage falls away quickly with depth, so a subsurface indication is always weaker than a surface one of the same size.<\/p>\n<p class=\"ts-p\">The field has to run across the flaw rather than along it. An encircling coil or a solenoid sets up a longitudinal field and finds flaws across the bar, and a current passed straight through the bar sets up a circumferential field and finds longitudinal flaws. Contact pads protect the bar from arc burns where the current enters. Alternating current travels near the surface and is not the choice for subsurface flaws, while direct current reaches further in. Because most bars hold little residual magnetism, the field is kept on during inspection, and finished bars are demagnetized afterwards so that chips do not cling during later machining.<\/p>\n<p class=\"ts-p\">The method is a fabricating shop tool rather than a mill tool. It is considered too slow and too costly for mass production inspection, so on bar it is used for a small quantity, or for a suspect group, rather than for the whole output of a rolling line.<\/p>\n\n<h2 class=\"ts-h2\">Ultrasonic inspection of drawn bar and wire<\/h2>\n<p class=\"ts-p\">Ultrasonic inspection sends sound at 1 to 25 MHz into the bar and reads the echo that comes back from a flaw. It finds internal flaws that no surface method can see, and it is used on large-diameter bar and wherever high integrity is specified. Its two weaknesses on bar are a couplant that has to be maintained, and a slower line speed than an electromagnetic method. On bar it is normally run alongside a surface method rather than instead of one.<\/p>\n<p class=\"ts-p\">The conventional normal-beam technique leaves an untested zone just under the surface, which is exactly where a cold-drawn bar carries its worst flaws. The angle-beam technique fills that zone, and running both together covers the whole cross section. In the published production systems the bar is fed straight while the probes rotate around it at speed, and guide sleeves and rollers hold the bar so that the incidence angle does not drift with vibration or bending. For flaws immediately under the surface the angle-beam record detects flaws as small as 0.2 to 0.3 mm, and echoes this small are beyond the normal-beam technique.<\/p>\n<div class=\"ts-table-wrap\">\n<table class=\"ts-table\">\n<thead>\n<tr>\n<th style=\"width:20%\">Parameter<\/th>\n<th style=\"width:27%\">Rotating probe, round bar<\/th>\n<th style=\"width:27%\">Twelve probes, hexagonal bar<\/th>\n<th>Rotating probe, cold-drawn wire<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr><td class=\"ts-grade\">Material dimension, mm (in.)<\/td><td class=\"ts-num\">15-32 (0.59-1.26)<\/td><td class=\"ts-num\">12-32 (0.472-1.260)<\/td><td class=\"ts-num\">15-30 (0.590-1.181)<\/td><\/tr>\n<tr><td class=\"ts-grade\">Testing method and frequency<\/td><td class=\"ts-num\">Normal beam and angle beam, 10 and 5 MHz<\/td><td class=\"ts-safe\">Normal beam, 6 channels, and angle beam, 6 channels, at 5 MHz<\/td><td class=\"ts-safe\">Normal beam 10 MHz, angle beam 5 MHz, surface wave 5 MHz<\/td><\/tr>\n<tr><td class=\"ts-grade\">Probe rotation, rev\/min<\/td><td class=\"ts-num\">1000<\/td><td class=\"ts-num\">Fixed in circumferential direction<\/td><td class=\"ts-num\">1000<\/td><\/tr>\n<tr><td class=\"ts-grade\">Signal transmission<\/td><td class=\"ts-num\">Noncontact rotation transmit<\/td><td class=\"ts-num\">Not stated<\/td><td class=\"ts-num\">Noncontact rotation transmit<\/td><\/tr>\n<tr><td class=\"ts-grade\">Marker<\/td><td class=\"ts-num\">One each for near-surface and inside flaws<\/td><td class=\"ts-num\">Two, near-surface and inside<\/td><td class=\"ts-num\">One each for near-surface and inside flaws<\/td><\/tr>\n<tr><td class=\"ts-grade\">Smallest flaw reported<\/td><td class=\"ts-safe\">0.2 to 0.3 mm (0.008 to 0.012 in.) at the near surface<\/td><td class=\"ts-safe\">0.3 mm (0.012 in.) near surface and 0.2 mm (0.008 in.) inside<\/td><td class=\"ts-safe\">0.1 mm (0.004 in.) surface depth and 0.2 mm (0.008 in.) inside<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"ts-tcap\"><em>Specifications of three published rotating-type ultrasonic flaw detection systems for cold-drawn round bar, cold-drawn hexagonal bar and cold-drawn wire, reproduced from Tables 1, 2 and 3 of Nondestructive Inspection of Steel Bar, Wire and Billets in ASM Handbook, Volume 17. Not stated marks a parameter the source does not give for that system. On the hexagonal line the six normal-beam and six angle-beam probes sit around the circumference so that the whole section is covered, and the coupling medium is a special oil chosen to avoid rusting the bar.<\/em><\/p>\n<p class=\"ts-p\">Wire draws on the same idea with three probe modes rather than two. A surface wave mode finds surface defects, an angle-beam mode finds near-surface defects, and a normal-beam mode finds defects inside the wire. The published results for that system give a minimum flaw depth of 0.1 mm on the surface and a minimum inside defect size of 0.2 mm, which lets the whole cross section of a cold-drawn wire be inspected in one pass.<\/p>\n\n<h2 class=\"ts-h2\">Eddy current and the rotating probe<\/h2>\n<p class=\"ts-p\">Eddy current inspection is the method that carries bar inspection in production. An alternating current in a coil induces currents in the bar, and a flaw, a change of grade or a change of hardness all disturb those currents in a way the instrument reports. An encircling coil alone is weak on a linear flaw, because a flaw that runs along the bar stays under the same part of the coil for its whole length. Rotating the probe around the bar describes a spiral over the surface instead, and a linear flaw then crosses the probe like any other defect.<\/p>\n<div class=\"ts-table-wrap\">\n<table class=\"ts-table\">\n<thead>\n<tr>\n<th style=\"width:24%\">Parameter<\/th>\n<th style=\"width:25%\">Rotating probe, Type I<\/th>\n<th style=\"width:25%\">Rotating probe, Type II<\/th>\n<th>Sheared bolt head<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr><td class=\"ts-grade\">Material dimension<\/td><td class=\"ts-num\">5-32 mm (0.197-1.260 in.)<\/td><td class=\"ts-num\">5-25 mm (0.197-0.984 in.)<\/td><td class=\"ts-num\">M20<\/td><\/tr>\n<tr><td class=\"ts-grade\">Number of probes<\/td><td class=\"ts-num\">2<\/td><td class=\"ts-num\">4<\/td><td class=\"ts-safe\">Rotating head, self induction and self comparison<\/td><\/tr>\n<tr><td class=\"ts-grade\">Probe area, mm2 (in.2)<\/td><td class=\"ts-num\">10 (0.016)<\/td><td class=\"ts-num\">5 (0.0078)<\/td><td class=\"ts-num\">Not stated<\/td><\/tr>\n<tr><td class=\"ts-grade\">Probe rotation, rev\/min<\/td><td class=\"ts-num\">3000<\/td><td class=\"ts-num\">6000<\/td><td class=\"ts-num\">300<\/td><\/tr>\n<tr><td class=\"ts-grade\">Testing frequency<\/td><td class=\"ts-num\">64 kHz<\/td><td class=\"ts-num\">512 kHz<\/td><td class=\"ts-num\">125 kHz<\/td><\/tr>\n<tr><td class=\"ts-grade\">Testing speed<\/td><td class=\"ts-num\">Not stated<\/td><td class=\"ts-num\">Not stated<\/td><td class=\"ts-num\">60 pieces per minute<\/td><\/tr>\n<tr><td class=\"ts-grade\">Smallest flaw reported<\/td><td class=\"ts-num\">0.1 mm (0.004 in.)<\/td><td class=\"ts-num\">0.1 mm (0.004 in.)<\/td><td class=\"ts-num\">0.3 mm (0.012 in.)<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"ts-tcap\"><em>Specifications of two published rotating probe eddy current systems for cold-drawn bar, in Table 4, and of one system for a cold-forged high-tension sheared bolt head, in Table 5, reproduced from Nondestructive Inspection of Steel Bar, Wire and Billets in ASM Handbook, Volume 17. On the drawn-bar systems the minimum detectable flaw depth is 0.1 mm, and at a feed of 60 m\/min the full surface is covered with a minimum detectable flaw length equal to the length of the probe coil. The bolt head carries a rougher surface, so its minimum detectable depth is 0.3 mm.<\/em><\/p>\n\n<h2 class=\"ts-h2\">How small a seam a permeability system will find<\/h2>\n<p class=\"ts-p\">The electromagnetic family also includes systems built on magnetic permeability rather than on conductivity, and these are the systems that both find flaws and sort material. A permeability system reads the change that a flaw or a change of condition makes to the magnetic state of the bar, so its reach is set by how much uniform residual stress the bar carries. The best detection comes from a bar that has been heat treated, quenched, drawn and machine straightened, and detection falls in steps through cold drawn and machine straightened stock, cold drawn and annealed stock, hot rolled stock that has been centerless ground, and finally plain hot rolled stock.<\/p>\n<p class=\"ts-p\">The practical figure on cold-drawn, machine-straightened round bar is a minimum detectable seam depth of about 0.025 mm for each 1.6 mm of bar diameter, and the same stock in a hexagonal or square section is more sensitive still because of the way the straightener works it. After straightening, the bars are aged for 24 to 48 hours at room temperature for best sensitivity, and a low-temperature stress relief up to 260 C can be used instead to shorten the wait.<\/p>\n<div class=\"ts-table-wrap\">\n<table class=\"ts-table\">\n<thead>\n<tr>\n<th style=\"width:40%\">Bar form and condition<\/th>\n<th>Smallest seam depth detected by the permeability system<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr><td class=\"ts-grade\">Round bar, cold drawn and machine straightened<\/td><td class=\"ts-safe\">About 0.025 mm (0.001 in.) for each 1.6 mm (1\/16 in.) of bar diameter<\/td><\/tr>\n<tr><td class=\"ts-grade\">Worked case, 25 mm (1 in.) round bar<\/td><td class=\"ts-safe\">A 0.41 mm (0.016 in.) seam is readily detected<\/td><\/tr>\n<tr><td class=\"ts-grade\">Same stock in hexagonal or square bar<\/td><td class=\"ts-safe\">0.30 to 0.33 mm (0.012 to 0.013 in.) is detected in the same processing<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"ts-tcap\"><em>Minimum seam depth detected by a magnetic permeability system on cold-drawn, machine straightened bar, reproduced from Nondestructive Inspection of Steel Bar, Wire and Billets in ASM Handbook, Volume 17. Under the surface the reach depends on carbon content, and the source gives approximately 6.4 mm for low-carbon steel, 7.9 mm for medium-carbon steel and up to 13 mm for many alloy steels.<\/em><\/p>\n<p class=\"ts-p\">Two further properties of that class of system matter on a purchase order. A larger drawing reduction lifts the flaw signal, so a bar drawn with a 1.6 mm reduction gives a signal about 50 percent larger than one drawn with the normal 0.8 mm reduction, and a 3.2 mm reduction gives about 90 percent more. The bar stock inspected by these systems runs from 4.8 to 140 mm in diameter, and the secondary coil has to be sized so that its inside diameter is 3.2 to 6.4 mm larger than the bar.<\/p>\n<p class=\"ts-p\">The other property is that a permeability system cannot inspect the ends of a bar. As the front and rear ends enter and leave the magnetic field the field is distorted, and the length lost at each end grows with bar diameter. At the average line speed of 37 to 46 m\/min the published figures are as follows.<\/p>\n<div class=\"ts-table-wrap\">\n<table class=\"ts-table\">\n<thead>\n<tr>\n<th>Bar diameter, mm<\/th>\n<th>Bar diameter, in.<\/th>\n<th>Noninspected length at each end, mm<\/th>\n<th>in.<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr><td class=\"ts-grade\">6.4-13<\/td><td class=\"ts-num\">1\/4-1\/2<\/td><td class=\"ts-num\">102-152<\/td><td class=\"ts-num\">4-6<\/td><\/tr>\n<tr><td class=\"ts-grade\">13-25<\/td><td class=\"ts-num\">1\/2-1<\/td><td class=\"ts-num\">152-203<\/td><td class=\"ts-num\">6-8<\/td><\/tr>\n<tr><td class=\"ts-grade\">25-50<\/td><td class=\"ts-num\">1-2<\/td><td class=\"ts-num\">203-305<\/td><td class=\"ts-num\">8-12<\/td><\/tr>\n<tr><td class=\"ts-grade\">50-75<\/td><td class=\"ts-num\">2-3<\/td><td class=\"ts-num\">305-406<\/td><td class=\"ts-num\">12-16<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"ts-tcap\"><em>Noninspected length at each end of a bar in a permeability system, reproduced from Nondestructive Inspection of Steel Bar, Wire and Billets in ASM Handbook, Volume 17. This end effect is why a flaw detection report on bar is normally quoted for the body of the bar rather than for the full length.<\/em><\/p>\n\n<h2 class=\"ts-h2\">Why billet is harder to inspect than bar<\/h2>\n<p class=\"ts-p\">A billet is less uniform in section and straightness than a bar and its surface is rougher, which makes both the setup and the reading harder. The surface is usually prepared first, by pickling in hot acid or by gritblasting, although tightly adherent scale does not interfere until it is thick enough to blunt the method. Magnetic particle inspection of billet is usually run wet and fluorescent, and the leakage field is not uniform across a flat face, since it is strongest at the centre of the face and almost absent at the corners.<\/p>\n<p class=\"ts-p\">The magnetization level for a billet follows a rule of thumb that is worth knowing when a report is quoted to a specification. Roughly 1000 Adc per 25 mm of material diameter is satisfactory for most critical inspection, which corresponds to an equivalent surface field of about 1.2 times 10 to the fourth A per m, or 157 Oe. Most practical large billet inspection runs at less than half of that. Particle size is chosen against the flaw that matters, and for rolled billet, where seams deeper than about 0.64 mm are the significant ones, particles of roughly 10 to 50 micrometres are used so that the large indications stand out and very minor ones are ignored.<\/p>\n<p class=\"ts-p\">On continuous-cast product the flaws change character. The slag pockets are near-surface inclusions, generally found within a 2.5 mm deep layer under the surface, and they run from less than 0.8 mm up to 3.2 to 6.4 mm in diameter. Cracks in continuous-cast product are deep and tight and can run with the oscillation marks or across them. Because the flaws are more subsurface and wider than a rolled seam, the magnetization level usually has to be higher than for rolled billet.<\/p>\n<p class=\"ts-p\">Eddy current inspection of billet has one clear advantage over magnetic particle, which is that it does not depend on the judgement of an operator, and it reaches the corners of the section as thoroughly as the flat faces. It cannot use an encircling coil, because a square billet cannot be fed through one, so it uses a rotary probe unit mounted on a drum and held against the face by a wear shoe and spring rollers. The speed of the probe over the surface has to be held inside a working band, and the published optimum for that test is 25 to 43 m\/min, since below the band the flaw depth reading becomes inconsistent and above it the electronics produce objectionable noise.<\/p>\n<div class=\"ts-dl\"><div class=\"ts-dl-txt\"><strong>Steel bar and billet inspection, printable PDF<\/strong> The four bar methods and their limits, the ultrasonic and eddy current system specifications, the seam depth rule and the end effect table, in one PDF with our contact details.<\/div> <a class=\"ts-dl-btn\" href=\"https:\/\/aobosteel.com\/wp-content\/uploads\/2026\/10\/Aobo-Steel-Steel-Bar-Billet-Inspection.pdf\" download> <svg viewBox=\"0 0 24 24\" aria-hidden=\"true\"><path d=\"M12 3v12m0 0 4.5-4.5M12 15l-4.5-4.5M4 20h16\"\/><\/svg> Download PDF <\/a><\/div>\n\n<h2 class=\"ts-h2\">Grades and stock<\/h2>\n<p class=\"ts-p\">The flaw types these methods are looking for are described one by one, with an illustration of each, on <a href=\"https:\/\/aobosteel.com\/steel-bar-defects\/\">the steel bar defects page<\/a>. The low-magnification examination that many mills run alongside flaw detection is set out on <a href=\"https:\/\/aobosteel.com\/tool-steel-bar-macroetch-carbide-segregation\/\">the macroetch and carbide segregation page<\/a>, and the way a bar is delivered and what its surface condition should be is on <a href=\"https:\/\/aobosteel.com\/tool-steel-bar-delivery-condition\/\">the bar delivery condition page<\/a>.<\/p>\n<p class=\"ts-p\">A flaw detection report is one document in the package, and the acceptance limits written into the order are what it is measured against. The wider verification set, including the test report itself, is collected on <a href=\"https:\/\/aobosteel.com\/tool-steel-quality-verification\/\">the tool steel quality verification page<\/a>. Where the flaw has to be sized once it is found, the measurement side is on <a href=\"https:\/\/aobosteel.com\/steel-inclusion-and-grain-size-measurement\/\">the inclusion and grain size page<\/a>.<\/p>\n\n<div class=\"ts-dl\"><div class=\"ts-dl-txt\"><strong>Steel bar and billet inspection, printable PDF<\/strong> The four bar methods and their limits, the ultrasonic and eddy current system specifications, the seam depth rule and the end effect table, in one PDF with our contact details.<\/div> <a class=\"ts-dl-btn\" href=\"https:\/\/aobosteel.com\/wp-content\/uploads\/2026\/10\/Aobo-Steel-Steel-Bar-Billet-Inspection.pdf\" download> <svg viewBox=\"0 0 24 24\" aria-hidden=\"true\"><path d=\"M12 3v12m0 0 4.5-4.5M12 15l-4.5-4.5M4 20h16\"\/><\/svg> Download PDF <\/a><\/div>\n\n<div class=\"ts-disclaimer\">\n<h3>Before you use these values<\/h3>\n<p>This page is a reference summary of published practice and it is not an Aobo Steel specification. The system specifications and the detection limits are reproduced from the source article, and the flaw size a line will actually catch depends on the calibration standard, the feed rate and the condition of the bar. Final acceptance is set by the purchase specification.<\/p>\n<\/div>\n\n<p class=\"ts-source\">Source: ASM Handbook, Volume 17, Nondestructive Evaluation and Quality Control, ASM International, 1989.<\/p>\n\n<\/div><\/div><\/section>\n\n","protected":false},"excerpt":{"rendered":"<p>Tool Steel | Bar and Billet | Flaw Detection How Steel Bar and Billet Are Inspected for Flaws A tool steel bar reaches the buyer with a mill certificate and, on the larger sizes, a flaw detection report. The two halves of that package rest on very different methods, and the flaw report is the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-21332","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO 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Steel | Bar and Billet | Flaw Detection How Steel Bar and Billet Are Inspected for Flaws A tool steel bar reaches the buyer with a mill certificate and, on the larger sizes, a flaw detection report. 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