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New FAQ August 2023

For section " Metal Cutting in General "
QUESTION
工具系基準方式とは何ですか?
ANSWER
工具系基準方式とは、工具の刃先の選択された点を原点とする直交座標系のことです。この座標系の平面は、工具の切削形状を決定する角度を指定するために使用されます。
QUESTION
How is the reference system for planes selected?
ANSWER
The reference systems for planes are defined in the following manner: - the tool-in hand system, which specifies a tool cutting geometry for design, manufacturing, and measuring process of the tool. - the tool-in-use system is used to specify the cutting geometry of the tool in use. - the machine system is intended for checking the geometry when the tool is mounted in a machine. The tool-in-hand system relates to the element of a tool that is chosen as a base (datum). The tool-in-use system is aligned with the resultant cutting motion in a machining operation. The machining system uses the direction of primary motion as reference.
QUESTION
What are the main mechanisms of tool wear?
ANSWER
The main mechanisms of tool wear are as follows: - Abrasive wear, is due to the heterogeneous metallurgical structure of the workpiece material, that features particles of different hardness. This causes the tool to be exposed to impact like abrasive machining and the removal of cutting material from the tool. - Mechanical wear is caused due to excessive mechanical load that can lead to a damaged cutting edge. - Adhesive wear occurs at specific values of cutting speeds and temperature in the cutting zone, which results in tool areas being welded with the particles of the removed material. This forms a foreign reinforced material that becomes the cutting edge and changes the cutting geometry. - Oxidation wear happens when the oxygen in the air reacts with the upper layer of the cutting material under high temperature in the cutting zone. - Diffusion wear occurs because of the tool's joint diffusion of material particles, the machined workpiece, and the formed chips. This changes the composition of the cutting material and diminishes its cutting capabilities.
For section " Milling "
QUESTION
Which factors should be considered when determining the feed speed for milling by use of interpolation?
ANSWER
When determining the feed for milling by interpolation, it is important to consider that the feed speeds (feed rates) of the cutting edge and the mill axis are different. This is unlike straight-line milling. In milling by use of helical and circular interpolation, the programmed feed speed in most CNC machines refers specifically to the axis of the cutter. When milling inside surfaces by interpolation, the feed speed of the mill axis is slower than that of the cutting edge. Conversely, when milling outside surfaces by interpolation, the feed speed of the mill axis is faster than that of the cutting edge. It is necessary to consider the above difference in feed speeds when setting the cutting data.
For section " Shop Talk Professional slang "

WORD
Half hard
MEANING
A term that describes the medium-hardness of steel. It is often used to specify austenitic stainless-steel sheets that have been hardened through cold work (rolling) rather than heat treatment. The hardness level of stainless steel can be designated as 1/4 hard, 1/2 hard and fully hard depending on its level of hardness.