\n3<\/td>\n | 2250<\/td>\n | 71<\/td>\n | 600<\/td>\n | 43<\/td>\n | 5046<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n InT3\u00a0= Ina + blnV3<\/sub>\u00a0+ clnF3\u00a0\u00a0\u00a0<\/sub>(3)<\/p>\nTo facilitate the solution, define<\/p>\n A2<\/sub>=lnT1<\/sub>-lnT2<\/sub>,<\/p>\nA3<\/sub>=lnT1<\/sub>-lnT3<\/sub>\u00a0,<\/p>\nB2<\/sub>=lnV1<\/sub>-lnV2<\/sub>\u00a0,<\/p>\nB3=<\/sub>lnV1-<\/sub>lnV3<\/sub><\/p>\nC2<\/sub>=lnF1<\/sub>\u00a0-lnF2<\/sub><\/p>\nC3=lnF1<\/sub>– lnF3<\/sub>.<\/p>\nFeed index\u00a0c = (A2<\/sub>B3<\/sub>-a3<\/sub>b2<\/sub>)\/(c2<\/sub>b3<\/sub>\u00a0-c3<\/sub>b2<\/sub>), Speed index\u00a0b = (A2<\/sub>-C2<\/sub>\u00a0\u00d7\u00a0c)\/B2<\/sub>,Formula coefficient\u00a0a =lnT1<\/sub>\u00a0– b\u30fbV1<\/sub>-c\u30fbf1<\/sub>\u3002<\/p>\nAfter substituting the test data,\u00a0a = 3959619943, b = -0. 20209,c= -1.98728,\u00a0Therefore, the tool life formula should be<\/p>\n T = 3959619943 V\uff0d0.20209<\/sup>F-1.98728<\/sup><\/p>\nFormula extension and application limitations <\/strong>of carbide drill bits<\/strong><\/h2>\n(1) <\/b><\/strong>Derivation of the <\/b><\/strong>carbide drill bit working time <\/b><\/strong>formula<\/b><\/strong>\u00a0<\/b><\/strong><\/h3>\nBecause only three groups of representative tool data are needed (if the service life exceeds the set tool life, the hole diameter will be too large), the life prediction formula of drill tools on the same production line can be calculated. Therefore, this method has strong popularization. Taking other curved axis tools as an example, the cutting parameters are substituted into the above formula, the theoretical tool tip distance is calculated, and the theoretical life is calculated according to the machining depth of a single piece.<\/p>\n As shown in Table 2, there is little difference between the theoretical and actual life of most tools. It can be seen that the tool life still has high accuracy within a certain range.<\/p>\n Table 2 theoretical and actual life of cutting tools<\/p>\n \n\n\nTool number<\/td>\n | cutting speed<\/td>\n | Feed speed<\/td>\n | Drillspeed<\/td>\n | Actual tool tip distance<\/td>\n | Theoretical tool tip distance<\/td>\n | Error ratio<\/td>\n | Current life<\/td>\n<\/tr>\n | \n <\/td>\n | ( mm\/min)<\/strong><\/td>\n( mm\/min)<\/strong><\/td>\n( mm\/min)<\/strong><\/td>\n <\/td>\n | <\/td>\n | <\/td>\n | <\/td>\n<\/tr>\n | \nOP050ST02<\/strong><\/td>\n78<\/strong><\/td>\n450<\/strong><\/td>\n104<\/strong><\/td>\n8673<\/strong><\/td>\n8757<\/strong><\/td>\n-1%<\/strong><\/td>\n480<\/strong><\/td>\n<\/tr>\n\nOP050ST04<\/strong><\/td>\n52<\/strong><\/td>\n720<\/strong><\/td>\n176<\/strong><\/td>\n3548<\/strong><\/td>\n3739<\/strong><\/td>\n-5%<\/strong><\/td>\n280<\/strong><\/td>\n<\/tr>\n\nOP010ST04<\/strong><\/td>\n118<\/strong><\/td>\n700<\/strong><\/td>\n32<\/strong><\/td>\n3227<\/strong><\/td>\n3351<\/strong><\/td>\n-4%<\/strong><\/td>\n600<\/strong><\/td>\n<\/tr>\n\nOP010ST09<\/strong><\/td>\n50<\/strong><\/td>\n500<\/strong><\/td>\n71<\/strong><\/td>\n7138<\/strong><\/td>\n7766<\/strong><\/td>\n-9%<\/strong><\/td>\n1088<\/strong><\/td>\n<\/tr>\n\nOP010ST15<\/strong><\/td>\n65<\/strong><\/td>\n650<\/strong><\/td>\n91.5<\/strong><\/td>\n4599<\/strong><\/td>\n4373<\/strong><\/td>\n5%<\/strong><\/td>\n500<\/strong><\/td>\n<\/tr>\n\nOP010ST22<\/strong><\/td>\n68<\/strong><\/td>\n500<\/strong><\/td>\n48<\/strong><\/td>\n6840<\/strong><\/td>\n7309<\/strong><\/td>\n-7%<\/strong><\/td>\n1050<\/strong><\/td>\n<\/tr>\n\nOP100STO2<\/strong><\/td>\n79<\/strong><\/td>\n900<\/strong><\/td>\n50<\/strong><\/td>\n2182<\/strong><\/td>\n2207<\/strong><\/td>\n-1%<\/strong><\/td>\n500<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n(2) Formula limitations<\/b><\/strong><\/h3>\nIn the process of popularization, it is found that the formula has large deviation for the prediction results of large length diameter ratio and large diameter bits. Tools with large aspect ratio generally refer to tools with the ratio of length to diameter greater than 12, such as crankshaft oil passage hole drill. Due to the large aspect ratio and insufficient rigidity, it is more sensitive to the swing in the drilling process. In addition, the long drilling time and poor chip removal effect lead to the burning of the cutting edge after the accumulation of cutting heat. Therefore, the predicted life is higher than the actual life. Large diameter bit usually refers to the bit with a diameter greater than 12mm, such as the bit for drilling the center hole at the flange end of the crankshaft. The reason for the nonconformity of large diameter bit is not clear and needs to be studied in the future.<\/p>\n wniosek<\/strong><\/h2>\n\n- When machining nodular cast iron with carbide drill bits, the main wear form is drill tip wear. The common failure form after drill tip wear is large aperture or burr of machining port. The most serious case is broken blade or broken blade<\/li>\n
- The wear degree of drill tip can be monitored by detecting the axial force of drilling. When machining QT600 nodular cast iron crankshaft, the limit value of axial force is recommended to be 5500n.<\/li>\n
- The life prediction formula of carbide drilling bit\u00a0is applicable to the carbide drilling bit\u00a0used in most mechanical crankshaft production lines. However, for bits with aspect ratio above 12 and diameter above 12mm, the prediction error of bit life is large.<\/li>\n<\/ol>\n<\/div>\n
<\/p>","protected":false},"excerpt":{"rendered":" Using carbide drill bit to make holes on nodular cast iron is a\u00a0commonly taken choice\u00a0when\u00a0automobile engine crankshaft\u00a0is manufactured.\u00a0Although nodular cast iron has good ductility and fatigue strength, due to the\u00a0long chips\u00a0and poor performance\u00a0under processing , especially\u00a0under\u00a0drilling, nodular cast iron\u2019s\u00a0characteristics,including\u00a0high unit cutting heat and difficult chip removal,\u00a0lead to the service life of the carbide drilling bit…<\/p>","protected":false},"author":2,"featured_media":21814,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[92],"tags":[],"jetpack_featured_media_url":"https:\/\/www.meetyoucarbide.com\/wp-content\/uploads\/2023\/04\/\u56fe\u72472-2.png","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/posts\/21812"}],"collection":[{"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/comments?post=21812"}],"version-history":[{"count":0,"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/posts\/21812\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/media\/21814"}],"wp:attachment":[{"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/media?parent=21812"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/categories?post=21812"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.meetyoucarbide.com\/pl\/wp-json\/wp\/v2\/tags?post=21812"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}} | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |