Precision parts processing Surface Hardening of Nitriding

Precision parts processing Surface Hardening of Nitriding

    Precision CNC machining parts  Nitriding is somewhat similar to ordinary case hardening, but it uses a different material and treatment to create the hard surface constituents.

In this process the metal is heated to a temperature of around 950℉(510℃) and held there for a period of time in contact with ammonia gas. Nitrogen from the gas  is introduced into the steel, forming very  hard nitrides that are finely dispersed through the surface metal.

   Precision CNC machining parts Nitrogen has greater hardening ability with certain elements than with others, hence, special nitriding alloy steels have been developed.

Aluminum in the range of 1% to 1.5% has proved to be especially suitable in steel, in that it combines with the gas to form a very stable and hard constituent. The temperature of heating ranges from 925℉ to 1,050℉(495℃~565℃).

   Liquid nitriding utilizes molten cyanide salts  and, as in gas nitriding, the temperature is held below the transformation range. Liquid nitriding adds more nitrogen and less carbon than either cyaniding or carburizing in cyanide baths.

Case thickness of 0.001 to 0.012in.(0.03~0.30mm) is obtained, whereas for gas nitriding the case may be  as thick as 0.025 in.(0.64mm). In general the uses of the two-nitriding processes are similar.

   Nitriding develops extreme hardness in the surface of steel. This hardness ranges from 900 to 1,100 Brinell, which is considerably higher than that obtained by ordinary case hardening.

Nitriding steels, by virtue of their alloying content, are stronger than ordinary steels and respond readily to heat treatment. It is  recommended that these steels be machined and heat-treated before nitriding, because there is no scale or further work necessary after this process.

Fortunately, the interior structure and properties are not affected appreciably by the nitriding treatment and, because no quenching is necessary, there is little tendency to  warp, develop cracks, or change condition in any way. 

Precision CNC machining parts  The surface effectively resists corrosive action of water, saltwater spray, alkalies, crude oil, and natural gas.

   

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Renohopmt share with you Automatic Fixture Design

Renohopmt share with you Automatic Fixture Design 

China precision machining Traditional synchronous grippers for assembly equipment move parts to the gripper centre-line, assuring that the parts will be in a known position after they arc picked from a conveyor or nest. However, in some applications, forcing the part to the centre-line may damage cither the part or equipment. When the part is delicate and a small collision can result in scrap, when its location is fixed by a machine spindle or mould, or when tolerances are tight, it is preferable to make a gripper comply with the position of the part, rather than the other way around. For these tasks, Zaytran Inc. Of Elyria, Ohio, has created the GPN series of non- synchronous, compliant grippers. Because the force and synchronizations systems of the grippers are independent, the synchronization system can be replaced by a precision slide system without affecting gripper force. Gripper sizes range from 51b gripping force and 0.2 in. stroke to 40Glb gripping force and 6in stroke.

 China precision machining Grippers Production is characterized by batch-size becoming smaller and smaller and greater variety of products. Assembly, being the last production step, is particularly vulnerable to changes in schedules, batch-sizes, and product design. This situation is forcing many companies to put more effort into extensive rationalization and automation of assembly that  was  previouslyextensive rationalization and automation of assembly that was previously the case. Although the development of flexible fixtures fell quickly behind the development of flexible handling systems such as industrial robots, there are, nonetheless promising attempts to increase the flexibility of fixtures. The fact that fixtures are the essential product - specific investment of a production system intensifies the economic necessity to make the fixture system more flexible. 

   China precision machining Fixtures can be divided according to their flexibility into special fixtures, group fixtures, modular fixtures and highly flexible fixtures. Flexible fixtures are characterized by their high adaptability to different workpieces, and by low change-over time and expenditure.  

    There are several steps required to generate a fixture, in which a workpiece is fixed for a production task. The first step is to define the necessary position of the workpiece in the fixture, based on the unmachined or base pan, and the working features. Following this, a combination of stability planes must be selected. These stability planes constitute the fixture configuration in which the workpiece is fixed in the defined position, all the forces or torques are compensated,

and the necessary access to the working features is ensured. Finally, the necessary positions of moveable or modular fixture elements must be calculated- adjusted, or assembled, so that the workpiece is firmly fixed in the fixture. Through such a procedure the planning and documentation of the configuration and assembly of fixture can be automated. 

    The configuration task is to generate a combination of stability planes, such that fixture forces in these planes will result in workpiece and fixture stability. This task can be accomplished conventionally, interactively or in a nearly fully automated manner. The advantages of an interactive or automated configuration determination are a systematic fixture design process, a reduction of necessary designers, a shortening of lead time and better match to the working conditions. In short, a significant enhancement of fixture productivity and economy can be achieved China precision machining.

Precision parts processing Surface Hardening of Nitriding

Precision parts processing Surface Hardening of Nitriding

    Precision CNC machining parts Nitriding is somewhat similar to ordinary case hardening, but it uses a different material and treatment to create the hard surface constituents.

In this process the metal is heated to a temperature of around 950℉(510℃) and held there for a period of time in contact with ammonia gas. Nitrogen from the gas  is introduced into the steel, forming very  hard nitrides that are finely dispersed through the surface metal.

   Nitrogen has greater hardening ability with certain elements than with others, hence, special nitriding alloy steels have been developed.

  Precision CNC machining parts Aluminum in the range of 1% to 1.5% has proved to be especially suitable in steel, in that it combines with the gas to form a very stable and hard constituent. The temperature of heating ranges from 925℉ to 1,050℉(495℃~565℃).

   Liquid nitriding utilizes molten cyanide salts  and, as in gas nitriding, the temperature is held below the transformation range. Liquid nitriding adds more nitrogen and less carbon than either cyaniding or carburizing in cyanide baths.

Case thickness of 0.001 to 0.012in.(0.03~0.30mm) is obtained, whereas for gas nitriding the case may be  as thick as 0.025 in.(0.64mm). In general the uses of the two-nitriding processes are similar.

   Nitriding develops extreme hardness in the surface of steel. This hardness ranges from 900 to 1,100 Brinell, which is considerably higher than that obtained by ordinary case hardening.

Nitriding steels, by virtue of their alloying content, are stronger than ordinary steels and respond readily to heat treatment. It is  recommended that these steels be machined and heat-treated before nitriding, because there is no scale or further work necessary after this process.

 Precision CNC machining parts Fortunately, the interior structure and properties are not affected appreciably by the nitriding treatment and, because no quenching is necessary, there is little tendency to  warp, develop cracks, or change condition in any way. The surface effectively resists corrosive action of water, saltwater spray, alkalies, crude oil, and natural gas.

Types of Casting And manufacturing process

Types of  Casting  And manufacturing process

    Precision CNC machining parts Casting is a manufacturing process in which molten metal is poured or injected and allowed to solidify in a suitably  shaped mold cavity. During or after  cooling, the cast part is removed from the mold and then processed for delivery.

    Casting processes and cast-material technologies vary from simple to highly complex. Material and process selection  depends on the part’s complexity and function, the product’s quality specifications, and the projected cost  level.

     Castings are parts that are made close to their final dimensions by a casting process. With a history dating back 6,000  years, the various casting processes are  in a state of continuous refinement and evolution as technological advances are being made.

A:Sand Casting  

    Sand casting is used to make large parts (typically iron, but also bronze, brass, aluminum). Molten metal is poured into a mold cavity formed out of sand (natural or synthetic).

    The processes of sand casting are discussed in this section, including patterns, sprues and runners, design considerations, and casting allowance.

    The cavity in the sand is formed by using a pattern (an approximate duplicate of the real part), which are typically made out of wood, sometimes metal. The cavity is contained in an aggregate housed in a box called the flask.

    Core is a sand shape inserted into the mold to produce the internal features of the part such as holes or internal passages. Cores are placed in the cavity to form holes of the desired shapes. Core print is the region added to the pattern, core, or mold that is used to locate and support the core within the mold.

  Precision CNC machining parts  A riser is an extra void created in the mold to contain excessive molten material. The purpose of this is to feed the molten metal to the mold cavity as the molten metal solidifies and shrinks, and thereby  prevents voids in the main casting.

    In a two-part mold, which is typical of sand  castings, the upper half, including the top half of the pattern, flask, and core is called cope and  the lower half is called drag,  The parting line or the parting surface is line or surface that separates the cope and drag.

    The drag is first filled partially with sand, and the core  print, the cores, and the gating system are  placed near the parting line. The cope is then assembled to the drag, and the sand is poured on the cope half, covering the pattern, core and the gating system.

    The sand is compacted by vibration and mechanical means. Next, the cope is removed from the drag, and the pattern is carefully removed. The object is to remove the pattern without breaking the mold cavity.

    This is facilitated by designing a draft, a slight angular offset from the vertical to the vertical surfaces of the pattern. This is usually a minimum of 1.5mm(0.060in.), whichever is greater. The rougher the surface of the pattern, the more the draft to be provided.

    The molten material is poured into the pouring cup, which is part of the gating system that supplies the molten material to the mold cavity.

    Precision CNC machining partsThe vertical part of the gating system connected to the pouring cup is the sprue, and the horizontal portion is called the runners and finally to the multiple points where it is introduced to the mold cavity called the gates. 

    

    

    

cutting speed

cutting speed, precision metal parts feed rate is an important parameter in the CNC machine tool cutting parameters, mainly based on the machining accuracy and surface roughness and the tool, workpiece material properties, select the maximum feed rate, machine tool stiffness and feeding system performance limitations., near the corner of contouring feed rate should be appropriately reduced in order to overcome the inertia or process systems is caused by deformation in the contour around the corner "overtravel" or "under process" phenomenon. to determine the principles of the feed rate : When the workpiece quality requirements can be guaranteed, in order to improve production efficiency, can choose a higher feed rate generally selected in the range of 100 ~ 200mm/min. processing in high-speed steel cutting tools, cutting, machining deep hole or should choose a lower feed rate, generally 20 ~ 50mm/min select range of .3 when machining accuracy, surface roughness, the feed rate should be selected smaller, generally in the 20 ~ 50mm/min range within selected .4 tool air travel, especially long-distance back to zero, you can select the CNC system given the maximum feed rate.

  precision metal parts back to eat the knife amount (or side knife to eat the amount determined under the premise of ensuring the quality of the machined surface, the back of cut (ap) should be determined according to the stiffness of the machine tool, workpiece and tool under the conditions allowed by stiffness, should as much as possible so that the back of cut allowance equal to the workpiece, thus reducing the number of tool path, and increase productivity.

   precision metal partss machining centers with axial and neck power head, to achieve the linkage of the three coordinates. Polar coordinate interpolation instruction and cylindrical interpolation instruction program optimization and development, and the machining station repeated positioning error of the effective compensation, the initial fast and reliable precision milling on the side of the rotary to improve the machining accuracy and surface finish quality.

    

Types Of Commonly Used Tool Of The CNC Milling and Tool Type Selection

Types Of Commonly Used Tool Of The CNC Milling and Tool Type Selection

Precision CNC machining parts NC milling tool types, in order to adapt to high-speed, high efficiency and high degree of automation features of CNC machine tools, the tool is moving in the direction of standardization, universal and modular development, including the milling cutter and hole machining tool. meet the requirements of efficient and specific milling, developed for a variety of special purpose tool. There are many ways to the classification of the CNC milling tool tool structure can be divided into: (1) the overall style, ② mosaic, welding or machine clip connection, the clamp can be divided into translocation and indexable two ③ special type, such as composite tool, damping tool manufacturing tool materials can be divided into: (1) high-speed steel cutting tools, ② carbide cutting tools, (3) diamond tool, ④ other materials, cutting tools, such as cubic boron nitride cutting tools, ceramic cutting tools. from the cutting process can be divided into: flat end milling cutter, rounded end mills, ball end cutter and taper milling knives.

Machining Centers, Tool Type Selection

Precision CNC machining partsTool selection in CNC programming state of human-computer interaction should be based on the processing capacity of the machine tool, workpiece material properties, processing procedures, cutting parameters and other relevant factors, the correct selection of the tool and tool holder, tool selection The general principle is : easy to install, good rigidity, durability and high precision to meet the processing requirements under the premise, as we choose a shorter shank in order to improve the rigidity of tooling production, processing parts of the geometry is to select the tool type the main basis.

Precision CNC machining parts A milling cutter selection of machining curved parts, in order to ensure that cutting edge and contour is tangent to the cutting point, to avoid the blade and the workpiece contour interference, generally use the ball head knife, rough two-edged cutter, semi- finishing and finishing with four-blade cutter, milling the larger plane, generally use the blade inlaid disc cutter, milling flat or stepped surface in order to increase productivity and improve the surface roughness, generally universal cutter milling keyway, in order to ensure the dimensional accuracy of the slot, usually two-edged keyway cutter, posted on Free paper Download Center http://eng.hi138.com

2. hole machining tool selection. hole machining of CNC machine tools in general no drill mode, due to poor rigidity of the drill and cutting conditions, the selection of the drill diameter D should satisfy L / D ≤ 5 (L conditions for the drilling depth, the drill center drill before positioning to ensure the accuracy of the positioning of the hole processing, fine twist the choice of floating reamer reaming orifice want to chamfer, boring should try to use a symmetrical edge boring head, cutting, cut vibration to balance the boring; try to choose a thicker and shorter shank in order to reduce cutting vibration. economic type CNC machining, tool sharpening, measurement and replacement of more than manually, taking up the auxiliary long time, therefore, must be reasonable to arrange the order of the tool in general should follow the following principles: (1) to minimize tool quantity, ② a tool clamping to complete all processing site ③ rough finishing tool should be used separately, even if it is the same dimensions of the tool, ④ The first milling drill, ⑤ the first surface finished, two-dimensional contour finishing, (6) possible, as far as possible use of CNC machine tools, automatic tool changer, in order to improve production efficiency In addition, the durability and accuracy of the tool and the tool price relationships requires attention, in most cases, choose a good tool, although the increase in the cost of the tool, processing quality and the resulting efficiency can greatly reduce the overall processing costs. In short, according to heat treatment condition of the workpiece material, cutting performance, and allowance to choose good rigidity, high durability cutter is to give full play to the CNC milling machine production efficiency and access to the premise of a satisfactory quality of processing. 

   

On the application of precision milling technology in the processing center

On the application of precision milling technology in the processing center

Precision CNC machining parts  machinery manufacturing industry plays a very important position in the national economy as a whole, including metal cutting, basic and reliable precision machining means during the process of NC programming, tool selection and cutting the amount of very important, it is not only a huge effect on the quality of the parts to be processed, and can even determine the machine the efficacy of play and production safety is carried out smoothly in the preparation of the processing procedures, tool and cutting, the preparation of high-quality processing program premise.

Precision CNC machining parts  Machinery manufacturing industry plays a very important position in the national economy as a whole, precision metal cutting, basic and reliable means of processing, mechanical, electrical, electronic and other modern industrial sector plays an important role. Tools design, manufacture and use since ancient times is highly valued, here we are talking about tools, not only refers to the machine tool for machining, we are more concerned with the cutting tool. tool to promote the development of metal cutting technology. an extremely active and very critical factor, it can be said machining technology development, innovation, history is the history of tool development.

Precision CNC machining parts  introduced in 2008, the Little Giant company produced two milling machining center, but has not been able to truly part and universal CNC turning and milling machining center milling functions. Tool selection, machining path planning, cutting the amount of set programmers just set the parameters, you can automatically generate the NC program and transferred to the CNC machine tools to complete the processing, CNC machining, tool selection and cutting to determine the state of human-computer interaction, which is common machining stark contrast, it also requires the programmer must master the basic principles of tool selection and cutting to fully consider the characteristics of CNC machining, programming, study and master the CNC milling machining center, milling functions for complex shape, and accuracy require high precision machining of rotary part, to upgrade my unit of CNC precision machining capabilities, with a very important practical significance.