{"id":10726,"date":"2026-10-14T07:25:13","date_gmt":"2026-10-14T07:25:13","guid":{"rendered":"https:\/\/ychltools.com\/resources\/cast-iron-turning-inserts\/"},"modified":"2026-10-14T07:59:23","modified_gmt":"2026-10-14T07:59:23","slug":"cast-iron-turning-inserts","status":"publish","type":"page","link":"https:\/\/ychltools.com\/zh\/resources\/cast-iron-turning-inserts\/","title":{"rendered":"\u8f66\u524a\u5200\u7247 for \u94f8\u94c1 (ISO K)"},"content":{"rendered":"<p>\u94f8\u94c1 is, in most respects, the easiest common material to turn. The graphite in it acts as a lubricant, chips break into small pieces without any help, and the cutting forces are low. The problems are narrow and specific: <strong>abrasive wear<\/strong>, the <strong>casting skin<\/strong>, and <strong>interruption<\/strong>.<\/p>\n<h2>Real cutting data for ISO K<\/h2>\n<p>Aggregated from 1160 insert records published for cast iron in our catalogue:<\/p>\n<div class=\"ychl-art-table\">\n<table>\n<thead>\n<tr>\n<th>Parameter<\/th>\n<th>Full published range<\/th>\n<th>Typical (median)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Cutting speed vc<\/td>\n<td>50 \u2013 490 m\/min<\/td>\n<td><strong>95 \u2013 400 m\/min<\/strong><\/td>\n<\/tr>\n<tr>\n<td>Feed fn<\/td>\n<td>0.02 \u2013 1.50 mm\/rev<\/td>\n<td><strong>0.10 \u2013 0.40 mm\/rev<\/strong><\/td>\n<\/tr>\n<tr>\n<td>Depth of cut ap<\/td>\n<td>0.10 \u2013 10.00 mm<\/td>\n<td><strong>0.7 \u2013 3.5 mm<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>Grey cast iron (GJL\/GG) sits at the top of that range. Ductile \/ nodular iron (GJS\/GGG) is tougher and needs about 20\u201330% less speed. Austempered ductile iron (ADI) is harder again.<\/p>\n<h2>\u724c\u53f7s that work<\/h2>\n<p>Our most-stocked cast iron grades: <strong>AT202, AC102K, AC202K, AP251K, AC301K, AC100K, HS6120, AC151K, PB90, AC251P<\/strong>.<\/p>\n<p>\u94f8\u94c1 grades favour a tough substrate with a thick CVD coating, because the dominant wear mode is abrasion rather than heat. A fine-grain grade designed for steel finishing will abrade quickly here.<\/p>\n<h2>Handling the casting skin<\/h2>\n<p>The as-cast surface carries sand, scale and occasional hard spots. It will destroy an insert edge at normal speeds. Standard practice:<\/p>\n<ul>\n<li><strong>Reduce vc by 30\u201350% on the first pass<\/strong> that crosses the skin.<\/li>\n<li><strong>Increase ap<\/strong> so the cut goes under the skin rather than along it \u2014 at least 1\u20132 mm into clean metal.<\/li>\n<li>Use a <strong>tough grade and a honed edge<\/strong> for that first pass, then switch to a wear-resistant grade for the bulk.<\/li>\n<li>Where possible, <strong>start in a machined area<\/strong> or pre-machine the entry with a grinder.<\/li>\n<\/ul>\n<h2>Dry or wet?<\/h2>\n<p>Grey cast iron is normally machined <strong>dry<\/strong>. The reasons are practical: the chips are small and easy to extract, coolant turns them into a paste that packs into the machine, and thermal cycling from coolant can crack the edge. Dry is also cheaper and cleaner.<\/p>\n<p>Use coolant when: machining ductile iron at high speed, holding tight tolerances that need thermal stability, or when the dust has to be suppressed for health reasons. If you do use coolant on grey iron, use it continuously, never intermittently \u2014 intermittent coolant is what causes thermal cracking.<\/p>\n<h2>Geometry and chipbreakers<\/h2>\n<p>Because chips break by themselves, the chipbreaker matters less in cast iron than in steel. What matters more is <strong>edge strength<\/strong>:<\/p>\n<ul>\n<li>Use the <strong>largest nose radius<\/strong> the profile allows \u2014 it resists abrasion and spreads heat.<\/li>\n<li>Prefer <strong>negative geometry<\/strong> (CNMG, WNMG, SNMG) for roughing, or <strong>round \u5200\u7247 (RNMG)<\/strong> for the hardest skins and heaviest interruption.<\/li>\n<li>\u65ad\u5c51\u69fd most used for K in our catalogue: <strong>KD5, KC4, MM4, KC2, PB1, MV<\/strong>.<\/li>\n<\/ul>\n<h2>Wear to expect<\/h2>\n<ul>\n<li><strong>Flank wear<\/strong> \u2014 normal and gradual. Target failure mode.<\/li>\n<li><strong>Abrasion \/ micro-chipping at the edge<\/strong> \u2014 speed too high, or grade too soft, or you are cutting sand inclusions.<\/li>\n<li><strong>Edge breakage on the skin<\/strong> \u2014 reduce speed on entry, increase ap, tougher grade.<\/li>\n<\/ul>\n<h2>Where to start<\/h2>\n<ul>\n<li>General grey iron: <a href=\"\/zh\/turning-inserts\/cnmg\/cnmg-120408\/\">CNMG 120408<\/a> with a K grade, vc 150\u2013300, fn 0.15\u20130.35, ap 1\u20134<\/li>\n<li>Heavy roughing, scale, interruption: <a href=\"\/zh\/turning-inserts\/snmg\/\">SNMG 120408<\/a> or round \u5200\u7247<\/li>\n<li>\u9762\u94e3 cast iron: <a href=\"\/zh\/milling-inserts\/\">milling \u5200\u7247<\/a> with K grades, run dry<\/li>\n<\/ul>\n<h2>Related<\/h2>\n<ul>\n<li><a href=\"\/zh\/resources\/iso-513-material-groups\/\">ISO 513 material groups explained<\/a><\/li>\n<li><a href=\"\/zh\/resources\/carbide-grades-explained\/\">Carbide grades explained<\/a><\/li>\n<li><a href=\"\/zh\/resources\/turning-insert-selection-guide\/\">Turning insert selection guide<\/a><\/li>\n<\/ul>\n<h2>Standards and further reading<\/h2>\n<p>The material group definitions used throughout this site follow ISO 513. The manufacturer links below are independent technical references.<\/p>\n<ul>\n<li><a href=\"https:\/\/www.sandvik.coromant.com\/en-gb\/knowledge\/materials\" rel=\"nofollow noopener\" target=\"_blank\">Sandvik Coromant \u2013 \u6750\u6599 knowledge<\/a><\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Cast iron is, in most respects, the easiest common material to turn. The graphite in it acts as a lubricant, chips break into small pieces without any help, and the cutting forces are low. The problems are narrow and specific: abrasive wear, the casting skin, and interruption. Real cutting data for ISO K Aggregated from [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":2220,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":"","_ychl_meta_desc":"Cutting data, grades and geometry for grey, ductile and malleable cast iron - including how to handle the casting skin, and when to run dry.","_ychl_model_html":""},"class_list":["post-10726","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/pages\/10726","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/comments?post=10726"}],"version-history":[{"count":1,"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/pages\/10726\/revisions"}],"predecessor-version":[{"id":10737,"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/pages\/10726\/revisions\/10737"}],"up":[{"embeddable":true,"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/pages\/2220"}],"wp:attachment":[{"href":"https:\/\/ychltools.com\/zh\/wp-json\/wp\/v2\/media?parent=10726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}