Impact Sand common faults and quick solution
 Sand making equipment rise in mining machinery market in China, a rising star, Impact Sand is a type of sand making industry, the impact Sand generally used in the fragmentation of the industry of cement, stone, and institutional building sand chronology, Impact Sand production and efficiency than other types of crushing machine.
Impact Sand in the application process may be some failures, in order to work more efficiently, the staff need to understand the Sand often malfunction, and can quickly solve. Such as sand making machine at work, a strong body swing, especially because there may be several.
The first may crusher impeller wearing parts wear. If the impeller wearing parts badly worn will result in the Sand internal operation time is not smooth, causing the swing is too large, this time as long as more pieces of wearing parts, Sand internal impeller to reach equilibrium. Second is probably the feed particle size is too large equipment swing is too large, sand making machine in the design time, the maximum feed size of the equipment is generally 4-5 cm, in general, equipment, feed particle size can reach up to 4 cm when finished the amount of sand, if the feed cause the equipment swing, if the feed is too small, collision broken inadequate finished the amount of sand is difficult to achieve full compliance. There is also a reason Sand is also possible that the impeller blockage, impeller obstructions can also cause uneven feeding, body swing too much, and remove the impeller trail obstructions can be resolved The body swing big problem.
Can to resolve a situation that may arise of Impact Sand, Sand staff must master, master Sand fault solution, I believe they can save a lot of sand making process after the time, improve work efficiency, and create greater economic benefits for themselves

 Oil-immersed transformer failure is often divided into two kinds of internal failures and external failures.

    Internal failure of the various failures in the oil-immersed transformer tank, the main types are: asked short circuit occurs between the windings of each phase, turn to ask a short circuit occurs between the wire turns of the winding, winding or Lead occurred through the shell ground fault.

    External fault for the oil-filled transformer tank external insulating sleeve and pinout on a variety of failures, the main types are: ground insulation bushing flashover or broken through the shell) short-circuit "between the Lead phase asked failure caused by the transformer internal fault or winding deformation.

    Nature, the internal fault of oil-immersed transformer is generally divided into two categories of heat failure and electrical failure. The thermal fault is usually transformer overheating, internal local temperature. According to its severity, the thermal failure is often divided into mild overheating (generally less than 150 ° C) overheating, low temperature (150-300 ° C) temperature too high (300 ~ 700 ° C), high temperature overheating (generally higher than 700 ° C) Sui four kinds of failure conditions. Power failure usually refers to the failure of the transformer within the role of the high electric field strength, resulting in the decline or deterioration of insulation performance. Depending on the discharge energy density, power failure is divided into partial discharge, spark discharge, and high-energy arc discharge three fault type.

    Oil-immersed transformer fault involves a broader and more specific types of division of the circuit divided circuit failure, magnetic failure and oil line failure.

    Divided from the main structure of the transformer can be divided into winding failure, core failure, the failure of the oil and attachment failure. Customary type of transformer failure, common fault-prone location divided, such as insulation failure, core failure, tap failure.

    Oil-immersed transformer itself most severely affected in the current outbreak to the highest gas rate transformer export short-circuit fault, There is also a transformer leakage failure, failure of oil flow electrification protection malfunction failed.

    All these different types of faults, and some may reflect the thermal failure, and some may reflect a power failure, and some may not only reflect overheating fault and discharge fault exists, and the transformer leakage failure under normal circumstances may not exist characteristics of thermal or electrical failure.

 Since the Faraday discovered electromagnetic induction, first appeared a century ago, transformer dry-type transformers. Transformer capacity can not be bigger, the voltage can not do technically been extremely limited. Transformer oil to the transformer technology development has made an indelible achievements.

    This cheap, insulation and good thermal conductivity of the oil medium transformer range of applications has become very broad. At the same time, the transformer also some accidents, fire, explosion. A serious threat to people\\ s lives and property. All this the reason to blame the transformer oil body will burn. Especially the rapid growth of electricity consumption, distribution centers closer and closer to people\\ s activity center, safety comes first, and this distribution transformer capacity not large, the voltage will not dry-type transformers is no better the.

    The fifties and sixties of the last century in China abroad called \"OVDT open class B insulation, ventilation and cooling dry-type transformers. This dry-type transformer insulating materials of high prices, poor performance, and simple manufacturing process, making the transformer and low reliability, high failure rate. Did not get everyone\\ s approval. In fact, at that time, the foreign epoxy resin and of NOMEX? Paper.

    Thus, in Europe on the development of epoxy cast dry-type transformers, the United States on the development of the use of NOMEX? Paper for insulation OVDT \"open type, ventilation and cooling dry-type transformers. Then in France, the United States, DuPont has been UL certified NOMEX insulation specification developed SECURAMID \"VDT\" encapsulation, ventilation and cooling dry-type transformers.

The transformer is to use the principle of electromagnetic induction, AC power into another power equipment of different voltage, current and other parameters. Insulating liner, and stand within it, most of the organic combustible material such as paper, cotton yarn, cloth, wood, and a large number of insulating oil, such as 1000 kilowatts transformer is about 0.012 cubic meters of wood, paper material 40 kg, insulating oil ton.

      Therefore, the fire risk is easy to combustion, internal transformer in the event of a serious overload, short circuit, combustible insulation materials and insulating oil will be affected by heat or arc role, decompose and burn, and produce large amounts of gas, a dramatic increase in the transformer internal pressure , causing the shell burst, a lot of fuel injection, combustion of the oil flow to further expand the fire hazard and causing widespread power outages, affecting the normal production and life.

      The reason the operation of the transformer fire and explosion in the following areas:

      (A) damage to the insulation

      A coil insulation aging
      When the transformer is long-term overload will cause the coil heat, the insulation gradually aging, caused by the inter-turn short circuit, phase short circuit or shorted to ground, causing the transformer to combustion and explosion. Therefore, before the installation and operation, the transformer dielectric strength test, overload are not allowed in the running process.

      2 poor oil, the oil is too small
      The transformer insulating oil in the storage, transport or operation and maintenance of accidentally leaving to make the dielectric strength of a significant reduction in moisture content, impurities or other oil mixed with oil. Short circuit occurs when its dielectric strength decreases to a certain value. Insulating oil to place a long time before put into operation must be carried out laboratory tests, such as water, impurities, viscosity, breakdown strength, dielectric loss, dielectric constant and other. Should also be regular testing of oil running. Identify problems, and shall promptly take appropriate measures.

      Core insulation aging damage
      Insulation aging between the silicon steel sheet, or clamping the core of the bolt casing damage, so that the core to have a huge vortex, causing fever, leaving the temperature will also accelerate insulation aging. The transformer core shall also periodically test the dielectric strength (test methods and requirements and the coil is the same) and found that the dielectric strength less than the standard, to promptly replace the bolt sleeve or insulated core.

      4 careless maintenance, and destruction of insulation
      Hanging core overhaul, often due to accidentally coil insulation and ceramic casing damage. Porcelain bushing damage, if they continue to run, ranging from flashover, while short-circuit. Therefore, maintenance should be particularly careful not to damage the insulation. After the repair, shall be hand inventory tools (in case you missed the accident) in the fuel tank, check the various components, testing, insulation, etc., to confirm intact, safe and reliable in order to put into operation. In addition, when maintenance should pay attention to the lead safe distance to prevent flashover distance is not enough in the running, causing the accident.

      (B) The wire connection is bad

      Coil inside the connector, the connection point between the coil and lead to high, low-voltage porcelain bushing contact and tap on the contact, such as poor contact a local overheating, damage the coil insulation, short circuit or open circuit. At a high temperature arc, the same causes the insulating oil breaks down quickly, and produce large amounts of gas, the pressure surge, devastating the consequences are very serious.

      The wire connection is bad for the following reasons:
      1, the bolt loose.
      2, the welding is not strong.
      3, the tap contacts damaged.

      For the above reasons, we should take the following measures:
      A transformer outage maintenance, should be checked, poor contact of the bolt must be tightened. Transformer that can not be shutdown, the need for an external contact to check.
      Maintenance prior to welding must be welded surface clean, carefully check the quality of solder joints after soldering, solder joints to prevent the run-time off caused the accident.
      3, should switch into place by tightening the bolt, are convinced that everything is correct, are allowed to put into operation.

      (C) the load short-circuit
      When the transformer load short-circuit occurs, the transformer will bear a lot of short-circuit current, such as protection of system failure or the setting value is too large, there may be burned transformer, such accidents are not uncommon in the power supply system. To this end, the transformer must be installed on the short-circuit protection. Small transformers (especially in rural areas transformer), the general drop-out fuse located in the high-pressure side, the choice of the melt should be able to guarantee is the fuse in the transformer internal or casing at the short-circuit accident; low voltage side with a low voltage fuse protection, the melt should be able to ensure that each leads to the circuit to short circuit or overload fuse. In addition, the high voltage side of the transformer can also over-current relay to short-circuit and overload protection. Transformer operation, capacity, size, voltage level, there should be gas protection, differential protection, direction, protection, temperature protection, low voltage protection, over voltage protection and other facilities.

      (D) is poorly grounded
      Oil-immersed power transformer secondary neutral point of (380/220 volts) must be grounded. When the three-phase unbalanced load, the zero line there will be current. Such as the current ground contact resistance has a larger ground point will appear high temperature to ignite combustible material. To this end, the ground wire should always check point is connected to a complete fastening and grounding resistance should be tested periodically. In addition, should also be noted that in the operation of the sound of the transformer, to monitor changes in temperature rise at any time to view the oil level and oil color, unusual, and should take timely measures to ensure safety.

      (E) lightning overvoltage
      Oil-immersed power transformers, current, mostly attracted by the overhead line, it is vulnerable to the invasion of lightning overvoltage breakdown of transformer insulation, and even burned the transformer, causing a fire, it must take appropriate lightning protection measures.

The display is stylish and graceful, the appearance of the whole of the AOC L24DH99F LCD flat-panel TV to show the characteristics of the mature and yet stylish. The black body color with the correct, straight lines, revealed a robust and mature; slim frame design with a stylish and modern atmosphere Run of the plinth, the tales of this product.

The jaw crusher broken limestone to achieve the fineness of the problem is the focus of many of our customers, then in the end, this crushing fineness we how to seize it? Below for everyone to make a detailed introduction:
 
    Limestone use the effect of jaw crusher:
 
    A limestone crusher production capacity of between 600 ~ 800t / h, is a limestone crusher capacity of 25 to 40 times, an effective solution to the original limestone crusher operation rate due to low yield, no downtime .
 
    2 to be completed by a large piece of broken limestone. Maximum crushing particle size of 1000 × 1200mm, an effective solution to the original side of the limestone supply, while storage of large limestone can not be used.
 
    Finished Size is small, only 2 ~ 15mm, effective solution to the original limestone particle size, often blocking the valve is even affect the mill production.
 
    4 two materials are mixed, desulfurization of limestone mixed with a significant increase. The mixing amount can reach 60%, effectively reducing the cost of the raw materials and fuel.
 
    Electricity consumption declined. 1 ton of limestone power consumption decreased by 1-2KWh / t, the annual electricity savings of 100,000 yuan.
 
    Effective in improving the labor intensity and working environment. Due to the high degree of automation of the limestone crusher, without human contact materials, the labor conditions of workers is greatly improved.
 

The jaw crusher is a the Yuzhou mechanical introduction of domestic manufacturing of advanced technology experience broken machinery and equipment, jaw crusher is widely used in mineral processing, building materials, quarry and chemical industry, material crushing. The jaw crusher is imposed by the use of movable jaw kinetic energy of the material extrusion, bending, impact, shear and abrasive material crushing, the moving jaw is the most fragile parts, the moving jaw wear common form of The movable jaw, grinding holes, Yu Chau mechanical jaw crusher hole bug fixes? What is are two ways:

         One, take the hole re-welding, such a method is particularly suitable for the movable jaw in steel manufacturing, the first use of manual arc welding worn inside the hole, use surfacing to fill, and then re-extended spatial processing, and the bearing outer diameter reasonable match. Note the hole welding layer to thin, due to moving the jaw wall thickness in order to ensure that the surfacing will not happen deformation, re-processing within the hole to ensure the vertical centerline of the bore both ends of the movable jaw times to ensure movable jaw and other parts to form good relations with and with precision.

        To take bore casement to use the tool to the wear of the moving jaw, hole boring, select the two bearing jacket, the external diameter of the movable jaw wear holes in close co-ordination within the hole and rolling bearing outside diameter to match, bearing the coat framed and put in the hole in the movable jaw, six stable nail in order to ensure the set stable, can be installed between the jacket and the inner hole in the movable jaw. This method requires attention to the moving jaw thickness, moving jaw original hole diameter, bearing the coat thickness, bearing outer race thickness accuracy. Magnetic methods, the ability to adapt to the moving jaw material, especially for the welding performance of the moving jaw material, this method is convenient and simple.

7.2mm body thickness of the LG the E2290V become the world\\ s thinnest display products. Thin body gives users the perfect

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The appearance of the liquid crystal display of the LG E2290V

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The ball valve is a valve inside a common valve, use a large amount of consumption is also fast, Therefore, a reasonable maintenance, or can improve work efficiency, and can also reduce downtime, saving replacement costs.

Want the ball valve performance and stability, long life, you need to pay attention to the following factors:

A. Before use, the application of water to clean pipes and valve overcurrent part, to prevent residual iron filings and other debris into the valve body cavity.

Two. Ball valve in the closed state, the valve body still remains part of the media, but also under some pressure. In the maintenance of the ball valve, first close the ball valve shut-off valve, open the ball valve in need of repair, fully release the pressure of the internal body. If the electric ball valve or pneumatic valve, you should first disconnect the power and gas supply.

3. Generally soft seal ball valve PTFE (PTFE) as a sealing material, the seal valve sealing surface is made of metal surfacing. For cleaning, pipeline ball valves need to be cautious when removing to prevent damage to the seals leaked.

4. Removable flanged ball valves, flange bolts and nuts should be fixed, then all the nuts a little tight, and finally exert oneself fixed. Such as to force the first individual nut is fixed, and then fixed the other nut, between the flange due to uneven result in damage to the pad surface or rupture, leading to valve flange butt out of the media leak.

5 If the valve cleaning, the solvent used must be cleaned accessories that do not conflict, does not corrode. If the gas valve, you can use gasoline for cleaning. Other parts can generally use water to clean. Cleaning, thorough cleaning and clean residual dust, oil and other attachments, such as can not be cleaned with water, and can not damage the body and parts of the premise, the targeted use of alcohol and other cleaning agents to clean. After cleaning and other cleaning agents completely volatile after the assembly.

6. If in the course of the filler at a slight leak, you can slightly intensify the stem nut tight to leak stop can not continue to tighten.

7. Long-term open storage will result in the valve body and parts rust and not work properly. The ball valve should be water-resistant storage, waterproof, moisture, and cover flange tightly. Store more than 12 months, the valve should be used to re-testing to ensure stable performance.

 Focusing of the laser beam power density of up to 1010 ~ 12W/cm2, acting on the material can get up to 1012K / s cooling rate, this feature not only provides a strong foundation for the growth of new disciplines of materials science, but also for new materials or the implementation of the new functional surface provides an unprecedented tool. Created by laser cladding melt in high temperature gradient away from the equilibrium of the fast-cooling conditions, the solidification microstructure formation of a large number of supersaturated solid solution, metastable phase or a new phase, has been a large number of Institute confirmed. It provides manufacturing functionally graded situ particle reinforced composite layer of a new thermodynamic and kinetic conditions. The laser cladding technology to prepare new materials under extreme conditions, failure of parts to repair and re-manufacturing, an important foundation for the direct manufacturing of metal parts by the world scientific community and enterprises attach great importance to many.

    At present, the laser cladding can be prepared iron base, nickel base, cobalt, aluminum, titanium-, magnesium-based metal matrix composites. Classification function: can be prepared by a single or a combination of both the coating of a variety of functions such as: wear resistance, corrosion resistance, high temperature and special functional coatings. From the material which forms the coating system from the binary alloy system to a pluralistic system. The alloy composition of the multi-system design and versatility is an important development direction of future laser cladding materials.

    The latest research shows that the steel base metal materials in our engineering applications dominated. At the same time, the failure of metallic materials (such as corrosion, wear, fatigue, etc.) most of the parts in the work surface, need to strengthen the surface. Order to meet the conditions of service of the workpiece using chunks of situ particle reinforced steel matrix composite materials, not only a waste of materials, but also extremely costly. The other hand, from the perspective of bionics to examine the natural biological material, its composition within the outer dense to sparse performance for foreign hard and tough, and dense – sparse, hard – tough from outside to inside gradient, natural biological materials special structure to have a good use of performance. Engineering materials, special conditions of service and performance requirements, there is an urgent need to develop robust combination of performance gradient new surface metal matrix composites. Therefore, the use of laser cladding preparation and the substrate was the metallurgical bonding of the gradient function situ particle reinforced metal matrix composites is not only the urgent needs of the engineering practice, the inevitable trend of laser surface modification technology development. Laser cladding technology situ formation of particle reinforced metal matrix composites, functionally graded materials has been reported, but most remain in the organization, performance analysis, the control phase of the process parameters, enhanced relative to the size, spacing, and the volume occupied by can not reach control levels, the gradient function is through the formation of multi-layer coating, inevitably interface weak binding between layers, from the utility still have a long way. Preparation of particle size using laser cladding technique, the number and distribution of controlled strength and toughness appropriate match, the set of functionally gradient situ particle reinforced as one of Metal Matrix Composites in the future direction of development. The study will address:

● cladding material composition, organization, performance design techniques, tools and principles and the process to achieve control technology.
        
 

● Laser Cladding functionally graded situ particle reinforced metal matrix composite particles enhanced phase precipitates grow up and strengthen the thermodynamic and kinetic model.
 
● reinforcement particle morphology, structure, function, and composite biomimetic design and size, quantity, distribution control technology.

● coating composition, organization and performance gradient control theory, the critical factors and process methods.

Macro-and micro interface, observe, analyze, control and characterization; functionally graded situ particle reinforced wear behavior of the analysis and testing of the routine performance of metal matrix composites as well as different operating conditions and failure mechanisms.

    Breakthroughs in these studies, it is possible to solve the problem of compatibility of the coating and substrate do not match, are prone to crack, and promote the broadening of the laser cladding applications.