Technical Description. CNC Turning

Transcription

1 Technical Description CNC Turning 0

2 The following is the minimum requirement for this skill for the Emirates Competition. The Technical Description consists of the following: Content: 1- Introduction 2 2- Competency and Scope of Work 2 3- The Test Project 3 4- Assessment 11 1

3 1. Introduction: CNC machining is a process used to produce workpieces through metal cutting using computer numerically controlled (CNC) turning and milling machines. In this competition, the competitor will have to demonstrate the knowledge and skills necessary to create turning CNC programs from a technical drawing to simulate the fabrication of the desired work part, using the MTS Simulator TOPCAM V7.4. The competitors are to complete a Test Project designed for typical industrial machining workshop. The format of the Test Project is composed of two standalone modules. The Test Project will be worked on over the two days of the competition. One module will be completed each day for all competitors, so that progressive marking can take place, and results to be made available at the end of each day. 1.2 Scope of application: Every expert and Competitor must know this Technical Description.In the event the English version takes precedence. 2. Competency and scope of work: The competition is a demonstration and assessment of the competencies associated with this skill. The Test Project consists of practical work only, which is programming and simulation of the fabrication process using the MTS Simulator TOPCAM V Practical Work: Competitors have to carry out the following tasks independently: Prepare, based on the drawing, usable CNC Program. Calculate the points of intersection on the profiles if not shown on the drawing Select the appropriate tools. The program must be optimized and corrected by competitors independently. 2

4 Below is an example of a test project: 3.1 Day 1 Module 1: CNC Turning part 1 5 hours max. CNC Turning is a process used to produce cylindrical components through metal cutting using computer numerically controlled lathes. From a technical drawing, competitors must create a CNC program to simulate the fabrication of the desired part. Such parts are used everywhere in metal industries, such as automotive, tools and dies, aviation and even in the aerospace industries. Programming takes place through the MTS Simulator TOPCAM V7.4 using the FANC 21 programming language. The test could include programming of more than one part. (Demo version is available on Module 1 Day 1: (CNC Turning Project) Part 1: Competitors have to create an NC program to manufacture the compressed air fitting part shown in the drawing, Fig Programming takes place through the MTS TOPCAM V7.4 Simulator. 3

5 All dimensions are in mm Fig

6 Maximum Allowed Time: 5 hours. Given: Material: ("N\Aluminium\AlMg1"). Blank dimensions: ø 47 x L90 mm. Cutting tools to be selected from Table 1.1. Max. Spindle rotational speed limit: 2500 RPM. Maximum depth of cut should be limited to 2 mm. Threading parameters to be selected from Table 1.2 Cutting speed to be selected from Table 1.3 The finished work part should look like the parts shown in Fig.1.2 (a). Required Output: Create NC program to simulate the machining of the compressed air fitting shown in Fig. 1.1 using the MTS TOPCAM V 7.4 Simulator. Calculate the points of intersection on profiles if not shown on the drawings. Select the appropriate tools required to create the program from Table 1.1. Set the machining conditions (feed, speed, depth of cut ) required for proper machining. Facing is required on each side of the work part. The workpiece produced should be highly surface finished. 5

7 Fig. 1.2 (a) Fig. 1.2 (b) 6

8 Part 2: Competitors have to create an NC program to manufacture the compressed air fitting part shown in the drawing, Fig. 1.3 (a) and 1.3 (b). Programming takes place through the MTS TOPCAM V7.4 Simulator. Fig. 1.3 (a) Fig. 1.3 (b) 7

9 Maximum Allowed Time: 3 Hours Given: Material: ("N\Aluminium\AlMg1"). Blank dimensions: DS 33 x L42 mm. Cutting tools to be selected from Table 1.1. Max. Spindle rotational speed limit: 2500 RPM. Maximum depth of cut should be limited to 2 mm. Threading parameters to be selected from Table 1.2 Cutting speed to be selected from Table 1.3 The finished work part should look like the parts shown in Fig.1.2 (a). Clamping device: "DIN55028 A2\Lathe Chuck\KSF74-3AsB" Clamping device attachment: "AsB9V1.5x60\Step jaw\hb3- B09xL14_7_4xH20_14_7 Required Output: Create NC program to simulate the machining of the BOLT shown in Fig. 1.3 using the MTS TOPCAM V 7.4 Simulator. Calculate the points of intersection on profiles if not shown on the drawings. Select the appropriate tools required to create the program from Table 1.1. Set the machining conditions (feed, speed, depth of cut ) required for proper machining. Facing is required on each side of the work part. The workpiece produced should be highly surface finished. 8

10 Table 1.1: List of cutting tools List of Cutting Tools Corner tool left Corner Tool Left\CCMT _SCACR 0808 B 06_B " Corner Tool Left\DCMT _SDJCR 0808 B 06_B " "VDI10A\Corner Tool Left\VBMT _SVJCR 0808 C 06_B " Twist Drill Twist drill\ SPIBO HSS-k 10x81(133) R_E4-16ER 16x50 Twist Drill HSS S\SPIBO HSS-k 12x81(133) R_E4-16ER 16x50 External and Internal Threading tools Internal Thread Tool Postax\M60I R_A KR_E x44" Threading Tool Left\M60E R_E BR_B " Boring Bar Postaxial Boring Bar Postaxial\CCMT _A10H - SCLCR 06_E x44" Boring Bar Postaxial\CCMT _A10H - SCFCR 06_E x44" Recessing tools Recessing Tool\SE NL_EFS B08R_B " 9

11 Table 1.2: Standard parameters values for fine metric threads in mm Metric Major Diameter Pitch Outside Thread Internal thread i l i M20x h M20x M22x M22x M22x M24x M24x M24x Table 1.3: Cutting speed limits for different metals Metal Type Cutting speed in meters/min Cast Iron Mild Steel High Speed Steel Brass Bronze Aluminum Up to

12 4. Assessment: This section describes how the Experts will assess the Test Project/Modules. It also specifies the assessment specifications and procedures and requirements for marking. Assessment will be 100% objective Marking Criteria for module 1 (Turning part 1) day 1: Section Criterion Marks A Setup Sheet 8 B Correct selection of cutting tools 10 C Accurate selection of machining parameters (feed, 10 rotational speed, cutting depth) D Finished part dimensions 72 Total = Marking Criteria for module 2 (Turning part 2) - day 2: Section Criterion Marks A Setup Sheet 8 B Correct selection of cutting tools 10 C Accurate selection of machining parameters (feed, 10 rotational speed, cutting depth) D Finished part dimensions 72 Total = 100 N.B.: The final mark of the Test Project will be the average of the marks gained in each module. The distribution of marks may vary. 11