A Review of Current and New Measurement Techniques Used in Hot Die Forging Processes

Abstract

The work presents the possibilities of applying modern measuring techniques, classic and coordinate measuring techniques in the forging industry (various stages of technological sequence), with the use of various measuring tools, instruments and machines applied in workshop metrology. The work points to different aspects of measuring techniques used mainly for two groups of objects, emphasizing their important role in the context of safety (achieved forgings-products) and the significant measurement problems due to the extreme conditions in industrial hot forging processes. The first group comprises various measurements of forgings (control during and after forging and mechanical treatment). The second group includes measurements of the forging equipment involving a broadly understood quality control (geometrical characteristics, surface quality etc.), often combined with comprehensive control and durability analysis of forging tools. The work analyzes the possibility and validity of applying scanning techniques for direct control of the quality and change of the geometry of the tools in industrial forging processes, without the necessity of their disassembly, and also measurement systems of temperature, forces and displacement in forging processes.

Wear Analysis of Die Inserts in the Hot Forging Process of a Forked Type Forging Using Reverse Scanning Techniques

“…Selection of base surfaces is of critical significance in the reverse method, and this issue was discussed in works [12,16,18,20]. In the presented analysis of the yoke forging (Fig.…”

In-Line Dimensional Inspection of Warm-Die Forged Revolution Workpieces Using 3D Mesh Reconstruction

“…In the automotive and aeronautic industry, dimensional inspection of manufactured parts requires high precision methods to assess the quality of the final product. Currently, CMMs are one of the most common tools used to inspect forged workpieces due to their high precision [5]. However, CMMs are not suitable for in-line dimensional inspection of warm-die manufacturing parts due to: (1) their contact-based nature requires the workpieces to be in a cooled state to avoid damaging the measuring probe and, (2) taking measurements with the probe is highly time-consuming (even with cold workpieces).…”

“…Visual computing provides contact-avoiding technologies and methodologies for Reverse Engineering and dimensional inspection which improve the productivity and efficiency of such CAD CAM CAE processes [6]. While sacrificing accuracy to some extent, optical scanners have become an alternative for dimensional inspection of different kinds of warm-die manufacturing processes [5,7]. Table 1 presents a comparative of standard CMMs vs. optical scanner dimensional assessment.…”

“…The circular runout [4] of the forged revolution workpiece indicates the deviation between the punch orientation and the forming matrix axis.Standard tools for dimensional assessment of these workpieces rely on contact between the probe and the measured workpiece. Such is the case of Coordinate Measurement Machines (CMMs), which provide highly accurate measurements [5]. However, dimensional assessment with standard CMMs (and contact methods in general) is not convenient due to (1) the high temperatures directly affect (or even damage) the probe and, (2) long measurement times for the cooled-down workpieces.…”

The Use of 3D Scanning Methods to Evaluate the Hybrid Layer Used in Forging Tools in Order to Improve their Durability

“…The most commonly occurring (also the been tested) destructive mechanisms are: plastic deformation and abrasive wear in warm forging [3] and hot forging processes [4], thermal fatigue cracking [5][6][7] and thermo-mechanical fatigue [8]. Among them, the most extensively studied one is the mechanism of wear is abrasive wear, which prevails also in the process for cold forging [9,10]. For example, a comprehensive analysis of the major destructive mechanisms of tools in the forging process of car steering was presented in work [11].…”