Download - Heat Treatment and Tooling Design (1)
HEAT TREATMENT AND TOOLING DESIGN
MOHD HAKIMEE BIN ROSLAN NORSAIFUL BIN SHAARIMUHAMMAD AFFAN BIN AHMAD NORDINNIK ZARITH BALKIS BINTI AZMISITI MAISARAH BINTI MOHAMMAD NORNUR SHAHIRAH BINTI ZULKIFLINUR’ AFIFAH BINTI SHUKRI
DEFINITION HEAT TREATMENT
The controlled heating and cooling processes used to change the structure of a material and alter its physical and mechanical properties
HEAT TREATMENT CONSIDERATIONS
Segregation By Size & Material type Fixturing Preheat Soak (austenite) Quench (martensite transformation) Freeze (cryogenics) Temper.
PURPOSE Cause relief of internal stresses developed during
cold working,welding, casting, forging etc. Harden and strengthen metals. Improve machinability. Change grain size Soften metals for further (cold) working as in
wire drawing or cold rolling
PURPOSE Improve ductility and toughness Increase, heat, wear and corrosion resistance of
materials. Improve electrical and magnetic properties..
HEAT TREATMENT THEORY The various types of heat treating processes are
similar because they all involve the heating and coolling of metals; they differ in the heating temperatures and the cooling rates used and the final results.
Ferrous metals (metals with iron) are annealing, normalizing, hardening, and tempering.
Nonferrous metals can be annealed, but never tempered, normalized, or case hardened.
HEAT TREAMENT PROCESS annealing tempering normalizing hardening
HEAT TREATMENT PROCESS
PROPERTIES OF MATERIAL HARDNESS TOUGHNESS WEAR RESISTANCE MACHINABILITY BRITTLESNESS TENSILE STRENGTH SHEAR STRENGTH
HARDNESS the ability of a material to resist
penetration or indentation.it is also a means to measure one material againts another.normally, the harder the material the greater its tensile strength.
TOUGHNESS the ability of a material to absorb sudden
applied loads or shocks repeatedly without permanent deformation.
MACHINABILITY the measure of how well a material can be
machined. factors concerning machinability are cutting speed, tool life and surface finish.
INTRODUCTION TO TOOL DESIGN
Objectives• Reduce overall cost to manufacture a product• Increase production rate• Maintain quality• Reduce cost of tooling (cost effective)• Design safe and easy to use tools
Responsibilities of tool designer
� Cutting tools, tool holders and cutting fluids Machine tools� Jigs and fixtures� Gages and measuring instruments� Dies for sheet metal cutting and forming� Dies for forging, cold finishing and extrusion� Fixtures for welding, riveting and other �
mechanical fastening
The Tool Design Process � Statement and analysis of the problem Analysis of the requirements� Development of initial ideas� Development of design alternatives� Finalization of design ideas�
Statement of the problem Problem without tooling What the tool is supposed to do?- Drill four �
holes Bottleneck in assembly- Low productivity with �
out tooling
Analysis of the requirements
Must perform certain functions Must meet certain minimum precision � requirements Must keep the cost to a minimum� Must be available when the production schedule �
requires it Must be operated safely� Must meet other requirements such as adaptability to �
the machine tool, etc.
Types of tool Material Cutting Tools Workholding Devices Pressworking Tools Pressworking Tool Bending, Forming and Drawing Dies Tool Design for Inspection and Gaging Tooling for casting Tool design for joining process
Typical Tooling Example
Tooling Drawings• Do not crowd views• Analyze each cut• Use standard values• Use only the views necessary to define the part• Realistic, thoughtful tolerances• Shaft easier to change than hole• Use stock sizes if possible• Notes may be necessary
Tooling Layout
• Lay out the part (red is suggested)• Lay out cutting tools and holders• Indicate locating requirements• 3-2-1 locating planes• Indicate clamping requirements• Use full scale if possible• Indicate standard fixture parts• Identify each item with balloons and leaders
Safety as Related to Tool Design
Make drill jigs large enough to hold without the danger of spinning.
Small drill jigs should always be clamped in a �vise or against a bar or backstop.
Install plexiglass guards around all milling and �fIycutting operations where chips endanger workers or work areas.
� Safety should be designed into the tooling. Cutting should never be performed against a �
clamp, because of vibration and tool chatter. Instead, parts should be nested against pins in
order to take the cutter load. Rigidity and fool proofing should always be �
built into the tooling.
The ends .. Thank you