Traditional metal cleaning agent - petrol and caustic soda
in conventional metals cleaning, the main use of gasoline and caustic soda. But gasoline is a national shortage of energy sources, so this traditional method of metal cleaning a wide ranges of difficult to use. The actual results from the use of: (1) a good cleaning efficiency; (2) clean dry surface is relatively high. However, in general, the mechanical precision cleaning, gasoline in the future development process completely new replaced metal cleaning agent.
Another widely used cleaning materials for the caustic soda, it has a cleaning effect is good, inexpensive features, the current automotive and machine repair industry, there are still more common applications. Drawback is that there is a strong corrosive, non-ferrous metals and thus in all parts of the cleaning is disabled, is that some steel parts, if high precision, should be restricted. After washing with caustic soda, must be immediately washed with water to remove residual caustic soda on the surface of the parts. Nevertheless, parts will soon rust, despite the use of the second unit when added rust inhibitor rinse method to achieve a certain effect, but the overall effect is still not satisfactory. Cleaned with caustic soda cleaning equipment not only cause early damage, and alkali vapor can cause pollution to the environment, so when used to enhance protection.


Plasma cleaning introduced
1 the mechanism of plasma cleaning
Plasma is partially ionized gas, is a common substance solid, liquid, gaseous state other than the fourth. By the plasma electrons, ions, radicals, photons and other neutral particles. As the plasma electrons, ions and free radicals and other active particles exist, which itself is easy to react with the solid surface.
Plasma cleaning mechanism relies mainly on the activity of plasma particles in the "activation" to achieve the purpose of removing surface stains. On the reaction mechanism point of view, plasma cleaning process typically includes the following: inorganic gases are excited to plasma state; gas substances are adsorbed on the solid surface; groups adsorbed molecules and solid surface reaction product molecules; resolved to form a product gas molecules; reaction residues from the surface.
Plasma cleaning technology is the most important feature of object processing, regardless of the type of substrate, can be processed, for metals, semiconductors, oxides and most of the polymer materials, such as polypropylene, polyester, polyimide, polyvinyl ethane, ethylene, or Teflon, etc. can be a good deal, and to achieve the overall and partial and complex structure of the cleaning.
Plasma cleaning also has the following characteristics: easy to use digital technology, high degree of automation; with high-precision control, time control of high precision; correct plasma cleaning will not damage the surface layer, the surface quality is guaranteed ; because it is in a vacuum, do not pollute the environment, ensure the surface is not clean secondary pollution.

Category 2 plasma cleaning
2.1 Classification of reactions: the plasma react with the solid surface can be divided into physical reactions (ion bombardment) and chemical reactions. Physical reaction mechanism is activated particles bombarding the surface to be cleaned, so that contaminants from the surface of the vacuum pump was eventually sucked; a variety of active chemical reaction mechanism is the reaction of the particles and pollutants volatile substances, and then sucked by the vacuum pump volatile substances.
Physical reactions to plasma-based cleaning, also known as sputtering erosion (SPE) or ion milling (IM), the advantage is that in itself does not react chemically clean surface without leaving any oxide material can be cleaned to maintain chemical purity, corrosion anisotropy; drawback is that a lot of surface damage, the heat will have a great effect on the surface to be cleaned selectivity of different materials, the corrosion rate is low. The chemical reaction-based plasma cleaning advantages of a higher cleaning speed, selectivity, for more effective removal of organic pollutants, disadvantage is that in the surface oxide. And physical reactions compared to the shortcomings of chemical reactions are not easy to overcome. Two reaction mechanisms and surface morphology have a significant impact of different physical reactions to the surface at the molecular level within the more "rough", thus changing the surface of the adhesive properties. There is also a plasma cleaning the surface reaction mechanisms and chemical reactions in the physical reactions have played an important role, namely, reactive ion etching or reactive ion beam etching, two cleaning can promote each other, ion bombardment damage to the surface to be cleaned or weaken its bond the formation of atomic states, easily absorbed reactant ion collisions to be heated cleaning material, making it more prone to react; the effect is both good selectivity, cleaning rate, uniformity, but also a better direction.
Typical plasma physics argon plasma cleaning process is clean. It is inert argon gas, argon plasma and the surface does not react, but to clean the surface by ion bombardment. Typical plasma chemical oxygen plasma cleaning process is clean. Oxygen free radicals generated by the plasma is very lively, easy to react with hydrocarbons to produce carbon dioxide, carbon monoxide, volatile matter and water, thereby removing surface contaminants.
2.2 excitation frequency categories: state of the plasma density and excitation frequency has the following relationship: nc = 1.2425 × 108v2 which nc is the plasma density (cm-3), v for the excitation frequency (Hz).Plasma excitation frequency commonly used in three ways: the plasma excitation frequency of 40kHz ultrasonic plasma, 13.56MHz RF plasma as a plasma, 2.45GHz microwave plasma as a plasma.
Produced from different plasma bias is not the same. Ultrasound plasma self-bias of 1000V or so, the RF plasma self-bias of 250V or so, the self-bias microwave plasma is very low, only a few dozen volts, and three kinds of plasma mechanism. The reaction in ultrasonic plasma physical reaction occurs, the RF plasma reactions occur chemical reactions both have physical reactions, microwave plasma chemical reaction occurs. Plasma cleaning ultrasonic cleaning of the surface of the impact is greatest, and therefore most of the actual semiconductor manufacturing applications using RF plasma cleaning and microwave plasma cleaning.

There are eight steps in the LAN cable making procedure: drawing of the single strand copper and aluminum, single wire annealing, conductor stranding, insulation extrusion, cabling, inner sheath installation, armoring and outer sheath installation.

1. Drawing of the single strand copper and aluminum
The copper and aluminum material commonly used for cat 5e cable and cat 6 cable production goes through one or several die holes of the drawing machine at room temperature, decreasing its cross-section, increasing its length and intensity. Drawing is the first of the wire and cable manufacturing procedure. Its main process parameter is mode technology.
2. Single wire annealing
The copper and aluminum filament is heated to a certain temperature and recrystallized in order to improve its toughness and reduce its strength, meeting the requirements of cable manufacturing for the conductive wire core. The key of this procedure is to eliminate the oxidation of copper.
3. Conductor stranding
In order to improve the flexibility of the wire and cable for convenient installation, the conductive core is made up of multiple single-stranded wires. The conductive core takes two forms, regularly stranded and irregularly stranded. And the irregular stranded is divided into bunch stranded, concentrically stranded, specially stranded and so on.
To reduce the area occupied by the wire and the cable geometry, the stranded conductors are pressed in the form, turning the ordinary round shape into semi-circular, fan-shape, tile-shape, and highly pressed round shape. Such conductors are used in power cables, rg6 coaxial cable and cat5e patch cord.
4. Insulation extrusion
The plastic wire and cable mainly adopts extruded solid insulation and plastic insulation technology:
4.1. Eccentricity: the extruded thickness deviation of the insulation is an important indicator of the level of extrusion technology; most of the product structure, size and standard deviation values are clearly defined.
4.2. Smoothness: the extruded surface of the insulation layer is required to be smooth, without any roughness, burns or impurities.
4.3. Density: The cross section of the extruded insulation layer is required to be dense and firm, without any visible pinholes or air bubbles.
5. Cabling
In order to ensure the molding exactness and minishing the size the multi-core cable, it is generally stranded into a circle. Its mechanism is similar to that of the conductor stranding. It adopts the “no back stranding” method for its relatively large pitch diameter. Technical requirements for cabling: first, avoid bending of the cable caused by turn over of the insulation core; second, avoid scratching of the insulation layer.
The cabling procedure goes along with the other two procedures: one is filling, to ensure the completeness and stability of the cable; the other is binding, to ensure that the cable core is not loose.
6. The inner sheath
To prevent the insulated core from being scraped by the sheath, the insulation layer should be protected appropriately. The inner sheath is divided into the insulation cover and the cushion rubber.
7. Armoring
The armor is installed on underground cables. It can bear a certain positive pressure. The structure of steel armor is available. If the cable is laid under positive pressure and tension (such as in water, in the vertical shaft or in the soil with large gap), the structure of steel armor should be adopted.
8. Outer sheath
The outer sheath is to prevent the wire and cable insulation from erosion. The main usage of the outer sheath is to enhance the mechanical strength of the wire and cable. It can also prevent chemical corrosion, moisture, water immersion and burning. The plastic outer sheaths are directly extruded using the plastic extruding machine.

The author writes for http://www.lancable8.com,we provide lan cable.