回转窑筒体对接操作方法

介绍了新筒体之间、新旧筒体以及旧筒体与旧筒体之间的母线法精准调整对接的具体操作步骤,以及对接安装施工时应注意的事项.该方法简单方便,有效保证了筒体的对接质量.     

浓硝酸用无纵缝铝制高压反应釜筒体的研制

本文介绍了浓硝酸用无纵缝铝制高压反应釜筒体的研制工艺，着重从材质，铸坯质量，变形率，道次分配和加热温度等方面讨论了对筒体耐蚀性能的影响，并对该筒体的使用效果与有缝筒作了比较。     

薄壁筒体卧置状态圆度的探索

简述了筒节圆度对壳体制造质量的影响、产生圆度的原因、测量筒节圆度的方法和确保筒节圆度的措施。提出了薄壁筒体卧置状态自重变形量的计算公式,可以较准确地知道筒节自重对筒节圆度影响的程度。     

回转窑筒体的设计经验和教训

0前言水泥回转窑筒体的设计包括窑支承点的选择、配置,筒体结构的设计和材质的选择以及制造工艺的确定。在设计回转窑筒体时,应保证筒体最小的径向变形和弯曲变形,并充分考虑材质和温度对许用弯曲应力的影响,以保证回转窑筒体的制造质量。本文结合实例,对回转窑筒体设计中的一些基本问题进行归纳总结,以期为水泥回转窑设计人员提供一些借鉴。1窑筒体支承点的选择1．l筒体出料端悬臂长一般来说,窑筒体出料端悬臂长度与窑冷却带长度有关。在设计回转窑筒体时,第一档支承点应尽量远离烧成带最高温度点。对于湿法长窑、干法中空窑和SP…     

大型超限PTA装置筒体制造防变形设计

以大型PTA装置制造为例,介绍了大型化工PTA装置筒体成型过程中的变形问题,分别分析了产生这些问题的原因以及应对措施。针对筒体制造出现的变形问题,设计一种新型的防变形筒体卷制工装,该工装的应用大大减小了筒体卷制中的变形,新型筒体卷制防变形工装可根据设备直径大小、长度进行调试,并提出另一种锥体焊接组对防变形方法。新型工装的设计提高了生产效率,满足筒体卷制完毕后水平度的要求,从而保证了设备的制造质量。     

多筒体自提升塔架式火炬安装方法

介绍了多筒体自提升塔架式火炬系统的组对、安装方法,包括火炬塔架、火炬筒、提升轨道的安装施工方法、质量控制措施。     

磁力半自动管道火焰切割机在回转窑改造现场的应用

水泥回转窑的现场改造,涉及到保留段原筒体的切割和坡口的开设工作,将开设好坡口的原旧筒体与新制作的筒体焊接组成新的回转窑筒体。保留段原筒体的切割和坡口开设工作,其传统和常用的做法是,手持氧气-乙炔火焰割枪切割,再用手持碳弧气刨开设坡口,为使保留段原筒体的端面和坡口达到与新筒体焊接的要求,现场还需用角磨机做很多打磨修补工作。磁力半自动管道火焰切割机在回转窑改造现场的成功应用,很好地完成了原旧筒体的切割和坡口开设工作,大大节省了人力、物力和时间,保证了保留段原筒体的端面质量。     

车载复合材料混凝土搅拌筒筒体的有限元分析

车载复合材料混凝土搅拌筒具有质量轻、耐腐蚀、保温性好、使用寿命长、可塑性强等优点,在国外已得到广泛应用,而目前国内关于车载复合材料混凝土搅拌筒的研究还很滞后,还没有相关的企事业单位从事该产品的研究与开发。鉴于此,本文利用ANSYS软件建立了车载复合材料混凝土搅拌筒筒体的有限元模型,并对搅拌筒自重、物料重量荷载作用下复合材料搅拌筒筒体的刚度及强度进行了计算与分析,旨在分析复合材料搅拌筒在混凝土搅拌车上应用的可靠性和适用性。     

浅析烟气脱硫塔筒体圆度和直线度的控制方法

烟气脱硫塔筒体的圆度影响烟气脱硫效果,筒体直线度影响塔内件的组对质量和塔体运行安全性,通过对比不同标准规范,从设计、制造、运输和组焊多方面提出筒体圆度和直线度的技术要求,从而严格控制各环节的产品质量,保证烟气脱硫塔的运行效果与安全。     

焊接滑环的关键技术论述

球磨机滑环是球磨机筒体的重要组成部分,随着球磨机筒体的大型化,原有传统的铸造滑环由于铸造工艺的问题,容易产生缺陷并且可焊性较差,无法满足大型筒体的技术及质量要求。而焊接滑环则可以有效解决铸造滑环的这两项缺陷,保证产品的技术及质量地要求。详细论述了焊接滑环的材料选型、卷制、热装配、焊接等关键过程的操作和要求,并对各环节中的一些传统工艺及设备改进,确保了焊接滑环的质量,使得球磨机大型化发展有了可靠的基础。     

复合材料高压气瓶用玻璃纤维开发研究

简要介绍了复合材料高压气瓶的发展状况、分类、特点以及相关标准。详细总结了复合材料高压气瓶用玻璃纤维的质量要求,研究开发了一种性能优异、适合于缠绕复合材料高压容器的玻璃纤维产品,并介绍了这种玻璃纤维产品的主要性能指标。     

PVC木塑复合材料生产中成型机的工艺控制

讨论了挤出机的机筒与螺杆装配精度、挤出工艺与PVC木塑复合材料塑化质量的关系,提出了调整、改善塑化质量的方法。     

与PVC异型材塑化质量相关的两个问题

从挤出机的挤出工艺和机筒、螺杆装配精度两方面讨论了与PVC异型材塑化质量的关系,提出了调整、改善塑化质量的方法。     

气瓶使用的危险性及爆炸事故后果分析

针对机械、冶金企业生产特点,阐述了氧气瓶、液化石油气瓶、丙烷气瓶、乙炔气瓶在生产中的危险性及事故后果,利用爆炸模型计算爆炸冲击波的致死半径,并提出安全使用气瓶的建议。     

Theoretical Description of a Two-dimensional Compaction Process of Cylinders

Two possible two-dimensional packing cases, one with slippery cylinders and the other with adhesive cylinders, were analyzed both experimentally and theoretically. In both cases, cylinders 10 mm in diameter and 16 mm in height were arranged inside a compaction apparatus in a random manner. The slippery cylinders were compacted to a maximum possible random closed array with little applied pressure, and virtually no further rearrangement was achieved, even by applying large additional pressure on the assembly. Compaction of the adhesive cylinders, on the other hand, occurred more gradually with applied pressure. Compaction of the cylinders resembled three-dimensional powder compaction.     

Correlation of strength of 75 mm diameter and 100 mm diameter cylinders for high strength concrete

Results of statistical analysis of test data are presented to establish if there is a correlation between the strength of 75- and 100-mm-diameter cylinders for concrete with strength between 110 and 160 MPa. A linear regression analysis showed that strength measured on 75-mm cylinders is within 5% of the corresponding strength measured on 100-mm cylinders. A more detailed analysis of the difference between the mean strengths of the two sizes of cylinder of each group of the tests indicated that 75- and 100-mm cylinders measure the concrete strength within 4%. It is concluded that 75-mm cylinders are suitable for compressive strength testing of high strength concrete (>100 MPa). For strength of concrete greater than 150 MPa, 75-mm cylinders are likely to measure smaller concrete strength than the corresponding 100-mm cylinders.     

Effect of age on splitting tensile strength and fracture resistance of concrete

Concrete cylinders aged 1,2,3,5,7,14 and 28 days were loaded to failure in indirect tension. Similar cylinders, but with a central notch cast in the diametral plane of loading, were also loaded to fracture. The splitting tensile strength of the notched cylinders was determined, and its behavior with age was compared with that of unnotched cylinders. Apparent fracture toughness values were calculated as a function of age. It appears that strength and fracture resistance follow similar aging patterns for the concrete tested.     

Effectiveness of hybrid drying

The aim of this paper is to examine the effectiveness of convective drying enhanced with microwave and infrared radiation. Four drying methods: convective, convective-microwave, convective-infrared and convective-microwave-infrared, were analyzed with respect to the length of the drying time by securing a good quality of dried products. To this aim the drying curves, the temperature of drying bodies, and the drying rates were determined experimentally and the appraisal of the dried product quality was made optically. The experiments were carried out on the kaolin samples in the form of cylinders. It was stated that a proper combination of these three drying methods may result in a very high drying rate and at the same time in a very good quality of the dried product.     

Natural convection mass transfer behaviour of vertical and horizontal cylinders embedded in an inert fixed bed of Raschig rings

Natural convection mass transfer at vertical and horizontal cylinders embedded in a fixed bed of Raschig rings was studied by an electrochemical technique which involves measuring the limiting current of copper deposition from acidified CuSO₄ solution. Variables studied were Raschig ring diameter, physical properties of the solution and cylinder height in case of vertical cylinders or cylinder diameter in case of horizontal cylinders. Under the present conditions where high porosity beds were used, a slight decrease in the rate of mass transfer was observed in the case of vertical cylinders whereas no rate decrease was observed in the case of horizontal cylinders in the bed. Implication of the present results for the design of fixed bed reactors operating at low feed rates and containing a vertical or horizontal array of tubes for heat exchange with the bed was noted.     

Stokes flow past periodic rows of porous cylinders

The flow of a viscous incompressible fluid at low Reynolds numbers in model filters—systems of porous permeable cylinders—is studied. A single row and hexagonal and square arrays of parallel cylinders perpendicular to the flow direction are considered. The flow field outside and inside a porous cylinder is determined by solving the Brinkman and Stokes equations. The drag force on a porous cylinder versus the cylinder permeability and the distance between the axes of neighboring cylinders is calculated. It is shown that rows of porous cylinders arranged into a square array have almost no mutual hydrodynamic effect at any array spacing. The cell model is shown to be applicable to the hexagonal array of porous cylinders over a wide range of packing densities.