Rapid prototyping technology and development

Rapid Prototyping (RP) technology, also known as rapid prototyping technology, is one of the rapidly developing manufacturing technologies in the world today. Rapid prototyping technology is a computer-controlled, based on the principle of discrete, stacked with different methods of accumulation of materials, and ultimately complete the parts of the forming and manufacturing technology.

1, from the forming point of view, the parts can be regarded as "point" or "surface" superposition. The geometrical information of "point" or "face" is discretized from the CAD electronic model, and then combined with the information of the forming process parameters, the material is regulated to accumulate the parts from point to surface and from surface to surface.

2, from the manufacturing point of view, it is based on CAD modeling to generate parts of the three-dimensional geometric information, control multi-dimensional system, by laser beam or other methods of material layer by layer to form a prototype or parts.

The main features of RP technology are:

1, rapid RP manufacturing technology is the concurrent engineering of complex prototyping or parts manufacturing an effective means to enable product design and mold production simultaneously, thereby enhancing R & D efficiency, shorten the product design cycle, greatly reducing the cost of new product development And risk, for the smaller size, shaped products are particularly applicable.

2, CAD / CAM technology integration Design and manufacture of integration has been a difficult point, computer-aided process (CAPP) at this stage because it can not and CAD, CAM completely seamless docking, which is restricting the manufacturing information And rapid prototyping technology integrated CAD, CAM, laser technology, numerical control technology, chemical engineering, material engineering and many other technologies, making the concept of design and manufacturing integration to achieve a perfect one.

3, complete reproduction of three-dimensional data through rapid prototyping and manufacturing of complete parts, complete true reproduction of three-dimensional modeling, regardless of the outer surface of the contour or the cavity of the shaped hole, can be true and accurate completion of modeling, basically no longer need to help External devices to repair.

4, a wide range of molding materials So far, all kinds of RP equipment used in a variety of materials, resin, nylon, plastic, paraffin, paper and metal or ceramic powder, basically meet the vast majority of products on the material Mechanical performance requirements.

5, to create significant economic benefits Compared with the traditional mechanical processing, development costs to save more than 10 times, the same rapid prototyping technology to shorten the enterprise product development cycle, so that in the new product development process of repeated revisions to the design of the program greatly Reduce, and basically eliminate the problem of modifying the mold, to create economic benefits is obvious.

6, the application of industry-wide RP technology After years of development, technically has basically formed a system, the same can be applied to the industry has gradually expanded, from product design to mold design and manufacturing, materials engineering, medical research, Culture and art, construction, etc. are gradually using the RP technology, making RP technology has broad prospects.

Direction of development

From the current RP technology research and application status, rapid prototyping technology for further research and development work mainly in the following areas:

(1) the development of good performance rapid prototyping materials, such as low cost, easy to shape, small deformation, high strength, durable and pollution-free forming material.

(2) to improve the processing speed RP system and open up the manufacturing process of parallel methods.

(3) to improve the reliability of the rapid prototyping system to improve its productivity and the ability to produce large pieces of equipment to optimize the structure, especially to improve the accuracy of forming parts, surface quality, mechanical and physical properties, for further mold processing and functional experiments provide the basis .

 (4) the development of rapid prototyping of high-performance RPM software. Improve the speed and accuracy of data processing, research and development using CAD raw data direct slicing method to reduce the STL format conversion and slicing process generated by the loss of accuracy.

(5) the development of new forming energy.

6) rapid prototyping method and process improvement and innovation. Direct metal forming technology will become the future research and application of another hot spot.

(7) rapid prototyping technology and CAD, CAE, RT, CAPP, CAM and high precision automatic measurement, reverse engineering integration research.

(8) to improve network services research efforts to achieve remote control.

transparent plastic products in medical application

As the plastic has a lightweight, good toughness, easy molding. Low cost, so in modern and daily products, more and more use of plastic instead of glass, especially for optical instruments and medical aspects, the development is particularly rapid. However, due to the requirements of its transparency is better, high wear resistance, impact toughness is better, so the composition of the plastic, the entire process of injection molding equipment. Mold, etc., have to make a lot of work to ensure that the plastic used to replace the glass, the surface quality is good, to achieve the requirements.

Transparent plastic must first have a high degree of transparency, followed by a certain degree of strength and wear resistance, to impact, heat resistance is better, chemical resistance is excellent, water absorption is small, only to use, to meet the transparency requirements and long-term deformation

This is the main properties of plastic products

Injection molding process characteristics of three kinds of commonly used transparent plastics

1, PMMA

The viscosity of PMMA is large, the fluidity is little, so it must be high temperature and high injection pressure. The injection pressure is helpful to improve the shrinkage of the product.

The injection temperature range is wide, the melting temperature is 160 DEG C, the decomposition temperature is up to 270 DEG C, so the material temperature adjustment range is wide, and the process is better. Therefore, improve liquidity, from the injection temperature.

2, PC

PC viscosity, melting temperature is high, poor liquidity must be at higher temperature injection (270~320 DEG C), relatively speaking, the temperature range is narrow, the process is not as good as PMMA.

Injection pressure has little effect on the fluidity, but because of the high viscosity, the injection pressure is still larger. To prevent internal stress, the holding time should be as short as possible.

High shrinkage rate, stable size, but the product of large internal stress, easy to crack, so should be used instead of increasing the temperature pressure to improve the liquidity, and by increasing the mold temperature, improve the mold structure and postprocessing to reduce the possible cracking.

3, PET

PET molding temperature is high, the material temperature adjustment range is narrow (260 - 300 DEG C), but after melting, the fluidity is good, therefore the craft is poor, and often in the nozzle to be added to prevent the flow device.

The mechanical strength and performance of the injection is not high, must be through the stretching process and modification to improve performance.

The accurate control of mold temperature is an important factor to prevent warpage.

At the same time transparent plastic products, easy to produce blooming

Blister Mold material selection

1, the choice of blister c mold

Blister mold generally have plaster mold, copper mold and aluminum mold

Gypsum mold: plaster molding in the semi-wet state, and then drying mold, plaster mold low cost, easy to modify, but the plaster mold precision is not high enough, the surface is not smooth and fragile is not durable, so it is often used to fight To do the electroplating of copper mold or some of the requirements of small-batch production of plastic mold.

Aluminum mold: with aluminum ingots through the machinery (lathes, milling machines, CNC, etc.) from processing.

Aluminum mold high precision, smooth surface and durable, but the price is very expensive, aluminum mold is generally used in high precision copper mold not reach the blister products.

Electroplated copper mold: Plaster mold made of samples, the plating layer of copper shell is the electroplating copper mold, the cost of relatively high plaster mold, but much cheaper than aluminum mold, because of its smooth and durable surface, low cost, electroplating Copper mold is the most commonly used a plastic mold.

2， the choice of plastic material

Blister packaging products include: bubble shells, trays, plastic boxes, as well as: vacuum cover, blister, and so on.

Blister products are only plastic sheet material, film thickness is generally not more than 1.5MM, commonly used sheet: PVC, PET, PP, PS and on this basis, flocking sheet, gold-plated sheet and anti-static sheet .

PVC: the most commonly used plastic material, soft, toughness, good plasticity, can be made transparent and a variety of colors, commonly used transparent PVC packaging electronics, cosmetics, toys, gifts and other products.

PET (A-PET): hard, good toughness, high strength, bright surface, environmentally friendly non-toxic, transparent and a variety of colors of the sheet. Disadvantages of PET high-frequency heat more difficult, the price is much more expensive than PVC, this material is often required to replace high-end and environmentally friendly products, PVC

PS: small density (light), environmental non-toxic, plasticity is very good, toughness is not easy to brittle, can not be made of transparent material, it can only be made at the end of care plastic, because of its easy to crack,

PP: material is particularly soft, tough, environmentally friendly non-toxic, high temperature, often made of food containers or other high temperature packaging products; but its poor plasticity, processing difficulties, poor surface gloss, and the processing of color change shallow.

PET-G: physical properties with the A-PET almost, but high-frequency heat, the price is more expensive than A-PET 80%

3, The determinants of price of plastic products

Blister = unit material cost of materials + energy + labor + transport + profits

Energy consumption: Blister is through the thermal processing, power consumption relative to other industries larger, roughly for the material cost of 8%

Artificial: Blister mainly by machine production, less artificial, roughly 10% of the cost of materials,

Transportation: According to the customer from the factory and distance,

Profit: Plastic factory net profit is generally low, 12% -20%, depending on the payment period, 30 days checkout is 14%

Material cost: The material cost of the product is relatively complicated. Before the calculation, the following data should be clarified:

Raw material price: according to the use of the product, to determine what kind of material and grade of material, to find the lowest price of this material suppliers

Film Thickness: Extending The product must be made of thick film, according to the shape of the thickness and shape of the various parts of the

The number of typesetting: according to the size and shape of the product, the number of molds can be calculated in a version, the density will reduce the quality of products, thinning will increase the material loss, so that the cost of material loss rate: the main factor is the product shape, The number and size of the chassis fit with the degree of plastic, the shape of the more Founder, the greater the output, the smaller the loss rate

In addition to blister mold, we are also good at injection mould  and injection molding.