introduction: There are many fine teeth on the surface﹑A hand tool for filing and smoothing work pieces。The application of the file was very early﹐The oldest file that has been found dates from BC1500Egyptian bronze rasp。Modern files are generally rolled with carbon steel﹑forge﹑anneal﹑grinding﹑It is processed by cutting teeth and quenching。There are many varieties of it。Divided by use﹕Common fitter file﹐For general filing processing﹔Wood rasp﹐Used for filing wood﹑Soft materials such as leather﹔Plastic file(what
2015-03-17 Reading quantity 2834
introduction:Countries all over the world are worried about the exhaustion of energy resources,The future of energy in some big countries will not hesitate to use knives and guns、Destroy all people,Although a world war is unlikely,But local wars continue,Some analysts see that,At present, the areas prone to war are mainly distributed in oil-producing countries。Our country should transform the previous extensive production road,Go smart and energy efficient,Actively respond to the national call to build an environmentally friendly and resource-saving model,Vigorously improve resource utilization,Turn waste into treasure。 Reducer industry as the basic industry in Chinas industry,Has formed a relatively mature industry system。In industry
2015-03-17 Reading quantity 2882
introduction: Brittle products are often due to material degradation during injection molding or other reasons。 ⑴Injection molding problem: The barrel temperature is low,Increase cylinder temperature;Low nozzle temperature,Raise it up;If the material is prone to thermal degradation,The temperature of the barrel nozzle is reduced;Increase injection speed;Increase injection pressure;Increase injection time;Increase total pressure time;Die temperature too low,Raise it up;The internal stress of the parts is large,Reduce internal stress;The pieces have patchwork stitches,Try to reduce or eliminate;Screw speed is too high to degrade the material。 ⑵Mold problem: ①The product design is too thin;②Gate tower
2015-03-17 Reading quantity 2808
introduction: Material name Theoretical weight(kilogram/meter) remark Flat steel、Steel plates、Strip steel W=0.00785×wide×thick 1.Specific gravity of steel7.85g/centimetre3compute Square steel W=0.00785×Length of side2 Round steel、Wire rod、Steel wire W=0.00617×diameter2 2.fvalue:General models and beltsaA surname3.34,withbA surname2.
2015-03-17 Reading quantity 2887
introduction:According to the use of parts and use conditions and environmental conditions to select the size、precision,fitFAGbearing[FAGbearing:The main shaft bearing is made of a solid inner ring、Outer ring、The ball、And a single row angular contact ball bearing consisting of a cage assembly with a solid window cage。]It is the premise of ensuring bearing life and reliability。 1、Site of use:Tapered roller bearings are suitable for bearing combined radial and axial loads mainly under radial loads,Usually in two setsFAGbearing[FAGbearing:The main shaft bearing is made of a solid inner ring、Outer ring、The ball、And a single row Angle composed of a cage assembly with a solid window cage
2015-03-17 Reading quantity 1571
introduction: The process of heat transfer when a liquid boils on a heating surface,It is a two-phase flow heat transfer with phase transition characteristics。When heating surface temperatureTWExceeding the saturation temperature of the liquidTSAnd reaches a certain value,The liquid forms bubbles at certain points on the heating surface。These points are called vaporization cores,It usually appears in small pits on heated surfaces。The bubbles form and grow、detach、Surface。The steam bubble absorbs a large amount of latent heat of vaporization during its formation and growth,The breaking off and rising motion of the bubble produce a violent disturbance,Therefore, boiling heat transfer is much stronger than convective heat transfer in a single phase fluid。After the bubble is removed from the heating surface,If the liquid has not reached saturation temperature,the
2015-03-17 Reading quantity 2807
introduction:cailiao wuli xingneng canshu Material physical property parameters physical property parameter of material Characterization of material in force、hot、light、Various properties reflected by physical actions such as electricity。The commonly used physical property parameters of materials are internal friction、Coefficient of thermal expansion、Thermal conductivity、Specific Heat Capacity、Resistivity and elastic modulus, etc。 Internal friction The phenomenon that the mechanical vibration energy of the material itself is gradually consumed during mechanical vibration。Its basic metric is vibration one
2015-03-17 Reading quantity 2935
introduction:1.Comparison of pickling passivation treatment methods method Scope of application Merits and demerits Impregnation method For parts that can be put into pickling or passivation tanks,But not suitable for large equipment The pickling solution can be used for a long time,High production efficiency、Low cost;Large volume equipment full of acid immersion liquid consumption is too large Brushing method Suitable for large equipment inside the surface and local treatment Physical engineering operation、Poor working conditions、The acid cannot be recovered Ointment method For installation or maintenance site,Especially for welding Manual operation、Poor working conditions、High production cost Spray method For installation site,Container wall with
2015-03-17 Reading quantity 1572
introduction:Six features of manual forklift trucks 1、Manual forklift with pallet cargo box,Containers can be transported in units,It not only reduces collisions,Scratches, etc,It also reduces the workload and stacking area,Greatly improve work efficiency。 2、The manual forklift adopts heavy steel column,Cold forming。Make the gantry stronger,safer,mobile,Easy to operate and labor saving。 3、The manual forklift cylinder adopts high precision grinding tube,Imported oil seal,One piece spool,Easy to unload and repair;The pressure relief method adopts foot step type,Smooth lifting speed,Greatly improved security
2015-03-17 Reading quantity 2802
introduction:A filter in which the suspension under pressure is continuously enriched in a flowing state over the filter medium。The dynamic filter uses pressure as the driving force,But it is different from the general pressure filter。The suspension in the dynamic filter always flows parallel to the filter surface(figure1[Working principle of dynamic filter]),The surface of the filter medium does not accumulate or only accumulates a thin layer of filter slag,Therefore, the filtration resistance caused by the filter slag layer is avoided or reduced。The concentration of the suspension in the flow state increased continuously,The final discharge from the filter is a liquid suspension concentrate that is still flowing。The filtration speed of this filter is several times higher than that of the plate and frame filter press with the same filtration area,The washing effect is better。
2015-03-17 Reading quantity 2788