2016年11月27日星期日

The design features of milling fixture

The design features of milling fixture  
As a result of milling and cutting force cutting more and more intermittent cutting edge, easy processing of vibration, so they should pay attention to the design of milling machine fixture: clamping force to be sufficient self-locking and anti-stroke; fixture installation to be accurate and reliable , that is, when the processing installation and the proper use of directional keys on the knife device; precision turned parts specific folder have sufficient stiffness and stability, the structure must be reasonable. 
 precision turned parts As a result of milling and cutting force cutting more and more intermittent cutting edge, easy processing of vibration, so they should pay attention to the design of milling machine fixture: clamping force to be sufficient self-locking and anti-stroke;fixture installation to be accurate and reliable , that is, when the processing installation and the proper use of directional keys on the knife device; specific folder have sufficient stiffness and stability, the structure must be reasonable. 
1. Directional keys
 Directional key position, also known as keys, installed on the bottom of the vertical slot fixture, generally with two, an in a straight line, the farther the distance, the higher the precision-oriented, with screw fastening in the specific folder.   Directional keys work with the milling machine with table-shaped slot in the machine tool fixture to determine the correct position; can absorb part of the cutting torque, reducing the load on clamping bolt to increase the stability of the fixture, so flat and some special drilling jig boring machine fixture is also frequently used.  Directional keys are rectangular and round two.
 2. Of the knife device
   precision turned parts precision turned partsDevices on the knife block and knife by the side of the foot of the fixture and tool used to determine the relative position. The structure of the form of a knife depends on the shape of the surface processing.
  Directional high-precision fixture should not be used or heavy directional keys, but in the specific folder on one elongated side processing as a base to look for is the installation location calibration fixture.Knife block on the pin and screw fastener commonly used in the specific folder, its location should be easy-to-use plug-foot on the knife, without prejudice to the workpiece loading and unloading. On the knife when the knife cutter block with a plug in between the feet with the knife tool to avoid direct contact block or cause damage to the knife blade block premature wear. Cypriot Cypriot feet are flat feet and two-foot cylindrical plug, the thickness and diameter of 3 ~ 5mm, manufacturing tolerance h6.

  Side of the knife block and feet have been standardized (the design can be found in the relevant manual), use the total fixture Sedat map scale should be marked on the knife block size and the work surface and positioning the location between the components. Devices should be installed on the blade of the knife and is easy to cut one end of the workpiece.
  
 precision turned parts

2016年11月20日星期日

The main types of milling machine fixture and structure of the form

The main types of milling machine fixture and structure of the form
  Milling fixture for machining parts on the main plane, groove, keyway, spline, and the gap as well as face shape. Precision metal parts Usually as a result of milling fixture table together with the feed movement, in different ways according to the feed milling fixture can be divided into straight-line feed type, feed circular mode and rely on three types of feed-type.
 1. Linear feed-type milling fixture
  This type of milling machine with the most. Precision metal parts Fixture installed in the milling machine table, the processing in a straight line with the feed table by way of movement.  According to the workpiece quality, structure and production quantities will be designed as a one-piece fixture points more than the parallel and more than a row followed by clamping of the linkage approach, sometimes the use of sub-degree institutions, both to improve production efficiency.
 2. Circle-type milling machine fixture feed  
Circle feed milling in the case of non-stop loading and unloading the workpiece, the general is a multi-tasking, and in the milling machine rotary table use.   Precision metal parts This fixture is compact and easy to operate, mobile time and auxiliary time overlap is high-performance milling fixture, for use in high-volume production.
  3. By mold milling fixture 

 Precision metal partsThis module depends on the milling machine with a fixture used in dedicated or universal milling machines on the processing of various non-circular surface. On the role of mold is to make access to supplementary motor workpiece to form a profile campaign. Movement by way of the main feed through mode can be divided into straight-line milling machine fixture and circle into the feed to the two.

 Precision metal parts

2016年11月13日星期日

Quenching&annealing and Tempering’s different

Quenching&annealing and Tempering’s different
When the term “annealing” is applied to ferrous alloys without qualification, full annealing is applied. Precision metal parts This is achieved by heating above the alloy’s transformation temperature, then applying a cooling cycle which provides maximum softness. This cycle may vary widely, depending on composition and characteristics of the specific alloy.
   Quenching is a rapid cooling of a steel or alloy from the austenitizing temperature by immersing the workpiece in a liquid or gaseous medium. Quenching medium commonly used include water, 5% brine, 5% caustic in an aqueous solution, oil, polymer solutions, or gas (usually air or nitrogen).
  Selection of a quenching medium depends largely on the hardenability of material and the mass of the material being treating (principally section thickness).
  Precision metal parts The cooling capabilities of the above-listed quenching media vary greatly. In selecting a quenching medium, it is best to avoid a solution that has more cooling power than is needed to achieve the results, thus minimizing the possibility of cracking and warp of the parts being treated. Modifications of the term quenching include direct quenching, fog quenching, hot quenching, interrupted quenching, selective quenching, spray quenching, and time quenching.

  Tempering. Precision metal parts In heat treating of ferrous alloys, tempering consists of reheating the austenitized and quench-hardened steel or iron to some preselected temperature that is below the lower transformation temperature (generally below 1300 or 705 ). Tempering offers a means of obtaining various combinations of mechanical properties. Tempering temperatures used for hardened steels are often no higher than 300 (150 ). The term tempering should not be confused with either process annealing or stress relieving. Even though time and temperature cycles for the three processes may be the same, the conditions of the materials being processed and the objectives may be different.

2016年11月6日星期日

Classification of Heat Treating Processes

Classification of Heat Treating Processes
 Precision CNC machining parts In some instancesheat treatment procedures are clear-cut in terms of technique and applicationwhereas in other instancesdescriptions or simple explanations are insufficient because the same technique frequently may be used to obtain different objectivesFor example, stress relieving and tempering are often accomplished with the same equipment and by use of identical time and temperature cyclesThe objectiveshoweverare different for the two processes
 The following descriptions of the principal heat treating processes are generally arranged according to their interrelationships
 Normalizing consists of heating a ferrous alloy to a suitable temperature (usually 50°F to 100°F or 28 to 56) above its specific upper transformation temperatureThis is followed by cooling in still air to at least some temperature well below its transformation temperature rangeFor low-carbon steels, the resulting structure and properties are the same as those achieved by full annealingfor most ferrous alloys, normalizing and annealing are not synonymous.
 Precision CNC machining parts  Normalizing usually is used as a conditioning treatment, notably for refining the grains of steels that have been subjected to high temperatures for forging or other hot working operations. The normalizing process usually is succeeded by another heat treating operation such as austenitizing for hardening, annealing, or tempering.

  Precision CNC machining parts Annealing is a generic term denoting a heat treatment that consists of heating to and holding at a suitable temperature followed by cooling at a suitable rate. It is used primarily to soften metallic materials, but also to simultaneously produce desired changes in other properties or in microstructure. The purpose of such changes may be, but is not confined to, improvement of machinability, facilitation of cold work (known as in-process annealing), improvement of mechanical or electrical properties, or to increase dimensional stability. When applied solely to relive stresses, it commonly is called stress-relief annealing, synonymous with stress relieving.
    
  Precision CNC machining parts