厚玻璃退火常见问题的解决方法

浮法玻璃退火常见问题主要是厚玻璃的切割难和边部炸裂，本文分析了问题产生的原因，并提出了采用烧边火等解决问题的方法，以改善玻璃边部应力，减少裂边，提高切裁率.     

汽车钢化玻璃边部应力分析与控制

通过对汽车用钢化玻璃边部应力产生原理、影响因素进行分析，提出了控制边部应力的有效方法，从而降低钢化玻璃的自爆率。     

石英坩埚内高纯隔离层在高效多晶硅铸锭中的应用

多晶硅铸锭过程中,石英坩埚侧壁中的杂质通过固相扩散进入并残留在多晶硅锭的边部,形成多晶硅锭边部的低少子寿命区(边部红区).本文通过在坩埚侧壁上制作三种不同成分的高纯隔离层来阻挡坩埚侧壁中的杂质向硅锭中的扩散,以降低硅锭中的边部红区比例.结果表明采用掺钡高纯隔离层可以使硅锭中的边部红区显著变窄,基本消除硅方中的边部红区.     

谈粉煤灰空心砖干燥裂纹的消除方法

粉煤灰空心砖坯体干燥过程中常常出现裂纹 ,既影响质量 ,也影响产量。其原因主要是砖机机头 (泥缸 )结构及安装部位不合理。空心砖成型过程 ,如果原料在泥缸中遇到挤压力度不同会导致泥条断面挤出速度不匀 ,坯体边部湿度、密实度与中间的湿度、密实度不一致 ,相同气候条件下 ,因坯体四周密实度低于中间 ,边部温度却高于中间而导致边部水分蒸发快 ,中间水分蒸发慢 ,形成边部脱水收缩率大于中间部的脱水收缩率 ,如果脱水收缩过快 ,砖坯体边部就会开裂并出现形状不同的裂纹。砖机机头 (泥缸 )的芯架由刀架、芯杆、芯头组成 ,如果刀架、芯头、芯…     

机立窑生产高强熟料

几年来,为提高立窑水泥质量,生产高强熟料,在生产实践中,采取了如下措施。1强化窑体保温众所周知,立窑煅烧过程中,边、中部物料所需要的烧成热耗不同。我国立窑窑墙普遍偏薄,一般仅500mm左右,增大了辐射热的损失,距边部70mm～120mm环形地带的物料由于与窑壁接触,煅烧过程中,部分热量为窑壁吸收并通过窑墙向外散失,同时,由于边部物料在煅烧过程中生产体积收缩形成边壁效应,边部气流流通大并带走一部分热量,使边部热量散失增加。为使立窑边、中部温度场尽量趋于一致,有关专家曾提出加厚窑墙的主张,煅烧带厚1000mm,其它部位700mm,这样,在窑边部…     

电加热引上窑——老厂改造挖潜的一个有效措施

秦皇岛玻璃厂一熔车间系九机平板有槽垂直引上窑。车间的6号引上机长期以来都是生产6毫米厚玻璃,一般一排炉的作业周期不超过20夭,1976年1～5月平均周期为19天。过去新炉一星期后就出现边部(特别是前边)较凉,原板边部较薄,边筋较重的现象。从炉内看,两边小砖必须加大,若底火减小或熄灭,就容易使边部玻璃液带起小砖造成大修或掉炉事故。     

LNG储罐06Ni9钢板板形控制

作为LNG储罐内罐关键材料的06Ni9钢板,其板形质量直接影响后续的切割、预制及现场安装。随着薄宽板(厚度5mm—8mm,宽度2400mm以上)运用越来越普遍,钢板生产中常见的平直度、边部切割质量问题等前端环节制约后续机加工。因此,加强钢板板形控制,对于方便内罐现场安装意义重大。本文分析了板形的影响因素,并从轧机类型、轧制工艺、淬火工艺、矫直、监检等环节采取控制措施,有效解决了薄宽板的板形问题。     

柔性玻璃弯曲断裂的研究分析

在制备柔性玻璃的过程中,出现了玻璃切割及弯曲时易断裂的现象。通过对刀轮切割及激光切割形貌分析,刀轮切割断口表面缺陷较少。对切割玻璃边部进行800℃火抛光处理,可使0.1 mm柔性玻璃曲率半径达到75 mm。     

数控火焰切割机切割质量影响因素和尺寸精度控制

对数控火焰切割机的质量控制因素与尺寸精度控制进行了分析和总结,并对不同厚度钢板的穿孔位置、切割速度与方向进行说明。     

提高玻璃基板切割精度控制

从切割尺寸精度控制的实质入手,找出导致玻璃基板切割尺寸变化的因素。结合生产中出现的情况以及有效的解决措施进行综合分析,对提高玻璃基板切割精度控制具有指导意义。     

Contact accuracy and orientations affecting the lapped tool sharpness of diamond cutting tools by mechanical lapping

In this paper, a brittle–ductile transition lapping mechanism is proposed for the mechanical lapping of single crystal diamond cutting tools. The critical depths of cut for brittle–ductile transition and the dynamic critical tensile stress are regarded as the references to analyze the influence of contact accuracy between the rapid rotating scaife and lapped tool surface and the effects of tool face orientation on the sharpened cutting edge radius, respectively. The experimental results indicate that the vibrations of lapping setup, surface quality of scaife, dynamic balance and motion accuracy of the spindle, lapping compression force and lapping velocity all have enormous influences on the contact accuracy so as to affect the lapped cutting edge radius of diamond cutting tools. Under the optimal settings of each influencing factor for a robust contact accuracy, a perfect diamond cutting tool is sharpened in ductile lapping mode with a cutting edge radius of 30–40 nm and a surface roughness Ra of 0.7 nm on the tool rake face. On the other side, different orientation settings of tool faces enable diamond cutting tools edge to have different micro mechanical strength. Under the same configurations of the lapping parameters, the higher the micro mechanical strength of tool cutting edge is, the smaller the sharpened cutting edge radius would be.     

Cutting edge damage in grinding of cemented carbides micro end mills

Micro mills are widely applied in the micro manufacturing and mainly fabricated using the grinding method. Cutting edges have significant influences on the performance of micro mills such as the micro mill life and machining quality. In this paper, the cutting edge damage mechanisms in the grinding of cemented carbides micro mills are investigated. The micro end mills grinding experiments are carried out and the cutting edge maximum edge damage width and surface roughness of the end teeth flank are measured. The results show that the micro fractures and micro cracks are generated in the cutting edge following micro pits in the grinding surface. The grain size and composition of cemented carbides have significant impacts on the damage of the cutting edge. The maximum edge damage width increases with the increase of Co binder content and WC grain sizes. However, a better flank quality with less micro pits is obtained as the reduction of Co binder content and grain size of WC.     

The influence of grain geometry and wear conditions on the material removal mechanism in silicon carbide grinding with single grain

High efficiency and precision grinding of brittle materials is challenging due to material physical and chemical properties. To understand the effect of grain geometry and wear conditions on the material removal mechanism in brittle material precision grinding, a single diamond grain grinding experiment was conducted on Silicon Carbide (SiC). The cutting edge radius and deflection angle were measured by confocal scanning. Under six different cutting edge radius and three maximum undeformed chip thickness, grinding force and ground surface were measured. Diamond grain wear was investigated by observing the grain morphology, wear rate, grinding force, and ground surface change over accumulative material removal volume. The result showed the existence of a critical cutting edge radius for improving SiC ground surface quality.. Normal grinding force increased with the cutting edge radius increase. Tangential grinding force increased with the cutting edge radius increase and reached the peak value at the critical cutting edge radius. Flank wear was the major wear mode in precision SiC grinding. The grain wear was associated with the grinding force and ground surface.     

浮法玻璃生产线冷端随动掰边和随动纵掰的应用

在当前经济和绿色环保环境下,越来越需要提高玻璃品质,降低生产成本,提高性价比。浮法玻璃生产线冷端为了满足生产线按等级和按规格分类取板的要求,自动化装备水平不断提高,可实现在线质量检测、优化切裁、随动掰边、随动纵掰,按质分类分片、堆垛、包装和仓储等功能,整个生产工序实现了自动控制。     

激光切割玻璃的研究进展

比较了利用激光和传统机械法的玻璃切割质量,着重介绍了玻璃激光切割中的裂纹控制切割法和熔融切割法,以及它们的研究进展.最后对飞秒激光切割玻璃的方法做了简要的介绍.     

国产钢丝绳芯输送带生产线升级改造

针对国产钢丝绳芯输送带生产线存在的钢丝绳初张力不稳定，钢丝绳磨损，钢丝绳恒张力误差大，成型车随机性左右摆动，带坯边胶切割劳动强度大、误差大，输送带断带方式笨重，生产线自动控制系统落后等问题，指出了切实可行的解决办法，使钢丝绳输送带质量产生了质的飞跃，同时改善了操作条件。使生产线的生产能力得到了有效发挥。     

高精度塑料零件的选材和机械加工

主要介绍高精度塑料零件的选材要求,研究塑料切削加工的特点,针对影响塑料切削加工质量的因素提出了具体的对策及经实践验证可改善和提高塑料切削加工质量的方法,探讨了铣切加工高精度塑料零件时的铣切工艺、铣切刀具和加工参数的选择原则。     

Nanopatterning of graphene with crystallographic orientation control

The recent papers on the nanopatterning of graphene and cutting of graphene nanoribbons were reviewed. It was found that until now the simultaneous control of crystallographic orientation and of the ribbon width in the range of nanometers was possible only by scanning tunneling lithography. The cutting process by local anodic oxidation under the AFM tip is a similar process, but due to the different physical interaction mechanisms of the STM and AFM tip with the substrate, and due to the larger radius of the AFM tip, the resolution of AFM lithography is poorer. The various cutting processes based on mobile, catalytic nanoparticles yield trenches with well defined crystallographic orientation, but have a major drawback: the location of the nanoparticles and the control of the direction in which the cutting will start are currently not predictable. The first promising results of a solid phase reduction reaction of the SiO₂ substrate at the graphene edge indicate the possibility of developing a new type of lithography that will allow the realization of complex nanopatterns. Recent results pointing to the possibility of the engineered modification of graphene edges may prove useful to all lithographic processes.     

提高直裁帘布接头质量的设备改造

<正>一、存在问题天津产90°裁断生产线安装使用以来,由于帘布自动接头的送料定位装置设计不合理,一直存在着定位挡板前后摆动、机架变形、晃动严重的现象,     

Performance of lightweight coated oxide ceramic composites for industrial high speed wood cutting tools: A step closer to market

The introduction of lightweight cutting tips in industrial wood machining could lead to machining at much higher speeds and thus greatly increase efficiency. One possible way to achieve this is through lightweight ceramic composites. An Al₂O₃ ceramic matrix was selected and reinforced with particles resulting in a density of approximately one quarter of the currently used heavy tungsten carbide tools (density of >15 g/cm³). Furthermore, a coating was applied to the ceramic cutting tools in order to increase the stability of the cutting edge. A combination of reduced coefficient of friction, frictional forces and a resulting decrease in temperature can lead to a reduction in chipping at the cutting tip. Chipping has always been the major drawback of ceramic cutting tools for industrial wood cutting. A ceramic composite containing 25 vol% of submicron and nano sized SiC particles shows good mechanical properties with HV₂=21.5 GPa and K_Ic=4.5 MPa m^1/2. This composition performed very well in industrial cutting trials on laminated beech. The cutting performance was increased further by use of an industrially available coating on the tools. The quality of the cut wood surface has always been difficult to characterize when comparing cutting tool materials and is often performed qualitatively by experienced carpenters by touch. The surface quality of the machined laminated beech was for the first time quantitatively characterized using Gelsight 2.5D tactile sensing.