When starting a new plastic injection molding project, plastic prototype parts ensure a product’s design is sound. For most plastic parts, a CNC machined prototype will provide exactly what is needed for testing. CNC machining allows for 85% of the form, fit and function testing of injection molded parts without having to produce injection mold tooling.
30
2016
11
21
2016
11
molding cycle in plastic injection
The complete injection process is called a molding cycle. The period between the start of the injection of the melt into the mold cavity and the opening of the mold is called the clamp close time. The total injection cycle time consists of the clamp close time plus the time required to open the mold, eject the plastic part, and close the mold again, the injection molding machine transfer the resin into molded parts through a melt down, injection, pack, and cool down cycle. A plastic injection molding machine includes the following major components as below.
07
2012
07
Medela BPA-free
Moms are searching for BPA-free products. In addition to our Breastmilk Feeding and Storage Bottles, which have always been BPA-free, all Medela products that come into contact with breastmilk are BPA-free.
Below are some common questions that will help you determine if a bottle is BPA-free and where you can find Medela BPA-free products.
20
2011
09
plastic injection processing
料加工之注塑工艺调校知识
23
2011
08
aluminum-diecasting-bobbin-dynamic_balance
Its bobbin casted by aluminum die casting have been passed the test of dynatic and static balance procisely.
23
2011
08
dynamic balance machine
dynamic balance machine
Balancing Machine for Automotive Drive Shaft
1.easy&safe to operate
2.visual display
3.high-precision
4.high efficiency
Our balanced test equipment which shows rotate speed,unbalance value, phase position in English and fingures is adopted with microcomputer test System.The unbalance value are directly diplayed by the unit of gram. There are 6 supporting petters can be selected,they are visual display and have the data momery.
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03
2010
12
Blow molding, also known as blow forming,
Blow molding, also known as blow forming, is a manufacturing process by which hollow plastic parts are formed. In general, there are three main types of blow molding: extrusion blow molding, injection blow molding, and stretch blow molding. The blow molding process begins with melting down the plastic and forming it into a parison or preform. The parison is a tube-like piece of plastic with a hole in one end in which compressed air can pass through.
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21
2010
04
The strength of this area is too weak and it is hard to cool because the steel is too thin
R>28. 滑块拆的位置 (The split line of slide block or the area of slide.)
29. 此处有尖角,填充困难 (It is hard to fill this area due to the sharp feature.)
30. 此处钢材太薄,强度不足而且不容易冷却
(The strength of this area is too weak and it is hard to cool because the steel is too thin.)
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31
2009
10
Electrical Standoff Insulators
Electrical Standoff Insulators
Although standoff insulators perform an ancillary function within most electrical systems, they can be critical for maintaining a device’s operational capability. A standoff insulator typically supports a conductor at a distance from the surface, or substrate, to which it is attached. The insulator’s high electrical resistance prevents the unintentional flow of current between a conductor and surrounding objects, effectively reducing the potential for power damage and energy waste.
Standoffs are used as separators in electronic and mechanical industries. They can be produced from a variety of materials, and come in a range of dimensional categories. For an insulator, the standoff format is particularly useful, as it eliminates any direct physical contact between electrical components that may cause them to short out. To better understand if standoff insulators are necessary for a given project, it may be helpful to review electrical operations as well as the different types of insulators currently available.
Conduction vs. Insulation
Conductors function under the principle that a charge will move through any material in which electrons can be excited. Perpetuating the charge builds energy and creates an electrical flow through a conductive substance. An insulator is any substance lacking the physical properties to excite electrons and extend the charge—this is usually due to the “band gap,” which constitutes the difference between a material’s valence (the strength of its atomic bonds) and its conductivity (the degree to which it can carry a current).
Insulators typically have strongly bonded valence electrons, preventing them from entering an excited state. However, if sufficient voltage is applied, the electrons will overcome their bonds and become charged, causing the insulator to become a conductor. This is usually accompanied by some form of material damage that alters the former insulator’s physical properties.
Insulating Materials
The material used to create an insulator can greatly influence its effectiveness in certain applications. Manufacturers typically produce porcelain insulators from clay, quartz, or feldspar rock. They can tolerate high voltage or electrical stress, and reliably regulate the flow of charge. In addition, porcelain has high tensile strength, corrosion resistance, and deformation resistance.
However, ceramics are susceptible to fracture due to their rigidity. Composite materials are common alternatives to ceramic-based insulators, as they alleviate the potential for cracking. A composite, such as a fiberglass core sheathed in rubber, can provide greater physical flexibility and moisture resistance, but with lower voltage tolerance and a faster rate of wear than its ceramic counterpart.
Plastic insulators are usually made from polymer resins, such as polypropylene or polyethylene. They are highly versatile and tend to be less expensive than ceramic or composite materials. Prolonged exposure to ultraviolet light can, however, increase their frailty and chance of shattering.
Standoff Insulator Applications
A standoff insulator is mounted at a distance from the electrical component it supports, and functions essentially as a threaded spacer. The most important specifications for a standoff insulator are its electricity clearance, mechanical strength, and mounting procedure. They are most commonly used for regulating current in conductors, or in conductive components of switchgear and transformers (though the units are typically designated by insulating medium rather than arrangement).
Due to the physical separation between the insulator and the component, standoffs usually control the flow of a high level of voltage, and significantly reduce the chances of inter-component shortages. This is especially useful in powering stations or electrical devices that have high energy requirements and electrically-sensitive equipment.
In deciding whether a standoff is right for a particular application, the insulating material, conductive strength, and environmental conditions are important factors. However, the proximity and electrical resistance of the device to be supported is likely the central concern in selecting an insulator.
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26
2009
10
Hot runner systems on the mould
Hot runner systems on the mould