THE REPAIRING OF ABRASION END PLAY OCCURRING IN BALL-SCREW ON CNC LATHES

Öz

Abstract. The aim of all the machine tools is to complete the work precisely in the shortest

time. Yet, due to different causes, electrical, electronic and mechanical defects have been on

the machines which cause economical loss. One of the most important mechanical defects

on the CNC lathe is abrasion of ball-screw. In time, the eroded ball-screw makes the move

difficult, ruins the precision of the lathe, and although everything is all right on the CNC lathe, the ball-screw causes the work-piece to be machined wrongly. In this study, abrasion of the ball-screw has been researched experimentally and detailed, micro structure of the balls has been investigated with microscope and loss of mass of the balls have been determined. In addition, the end play among screw-ball-nut caused by abrasion in ballscrew has been determined and a new approach has been presented about its repairing to use the ball-screw longer without changing.

Anahtar Kelimeler

• Abrasion,Ball-screw,CNC,Error

CNC TORNA TEZGAHLARINDA BiL YELi ViDALI MiLDE OLUSAN ASINMA BOSLUGUNUN GiDERiLMESi

Öz

Turn takrrn tezgahlannda arnac, isin en kisa stirede ve tam olcusunde islenmesidir.

Ancak cesitli sebeplerden dolayi tezgahlarda elektrik, elektronik ve mekanik

anzalar meydana gelmekte ve bu anzalar ekonomik kayiplara sebep olmaktadir.

Mekanik anzalann en onernlilerinden bir tanesi bilyeli vidah mil asmrnasidrr.

Zamanla asmari vidah mil ve bilyeler belirli bolgelerde hareketi zorlasnrmakta,

tezgah hassasiyetini ortadan kaldirrnakta ve tezgahta butun veriler normal olsa bile

is parcasmm olcu tamlrgiru olumsuz yonde etkilemektedir. Bu cahsmada, bilyeli

vidah milin ve bilyelerin asmmasi deneysel olarak aynntih bir sekilde arasnnlrrus,

mikroskopta bilyelerin mikro yapilan ve ktitle kayiplan incelenmistir. Aynca,

bilyeli vidah milde asmmadan dolayi olusan bosluk belirlenrnis ve sadece bilyeler

degistirilerek bilyeli vidah milin komplesinin yenisi ile degistirilmeden daha uzun

sureli kullamlmasi icin yeni bir yaklasim sunulmustur,

Anahtar Kelimeler

• Arrza,A$lnma,Bilyeli Vidali Mil,CNC

Kaynakça

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