多通道螺旋板式换热器几何设计

多通道螺旋板式换热器在设计上与单通道螺旋板式换热器有诸多不同之处。文章将介绍了多通道螺旋板换热器的设计及计算,并着重给出中心隔板、偏心距,有效换热面积、螺旋板圈数、螺旋板内半径、螺旋板起始角、螺旋板长度,螺旋体外径等计算公式。     

螺旋板换热器在精细化工生产上的应用

介绍了螺旋板换热器的结构特点，总结了螺旋板换热器在精细化工企业几个单元操作工序中成功应用的经验，提出了螺旋板换热器的使用要领及结构设计方面的改进意见。     

螺旋板换热器的外径计算方法探讨

螺旋板换热器的外径等于两螺旋板外侧线终点的极径之和,即DO=r1+r2。此方法不仅适用于半圆螺线的螺旋板换热器,也适用于阿基米德螺线的螺旋板换热器。     

螺旋板换热器的应用与设计

<正> 螺旋板式换热器在化工行业中广泛应用已久。近年来,很多工厂采用螺旋板换热器代替列管换热器,以解决小列管材料供货困难及增加单位体积换热器的换热面问题起到较好的作用。我省临湘县氮肥厂在变换工段将列管换热器改为螺旋板换热器曾作为经验介绍给兄弟厂,因阻力降较大,现又改为列管换热器。氨厂的合成塔内件很多用螺旋板     

新型螺旋板列管换热器的研究

提出与玉米千秆干燥机配套使用的新型螺旋板列管换热器,该换热器采用了螺旋板与两管相结合的新型换热原理,分析了螺旋板列管换热器的结构特性。其基本参数为供热量23．9×10^4kJ·h^-1,热风温度80～120℃,耗煤量24kg·h^-1,热效率75．8％。     

螺旋板换热器内水垢的清除方法

对平顶山京宝焦化公司一螺旋板换热器内结垢情况进行实例分析，确定结垢的原因和清洗方法，采用酸洗法对螺旋板换热器内的垢进行清除，经过16h的连续清洗，螺旋板换热器内的污垢全部清除，投入使用后，换热效果令人满意。     

螺旋板换热器在蒸氨系统中的设计与应用

介绍了螺旋板换热器的主要特点,以煤精厂蒸氨系统中螺旋板换热器为例进行了详细设计计算,该设备投入运行后生产稳定,较管壳式换热器具有明显的优势,取得了很好的经济效益和社会效益。     

可拆式螺旋板换热器设计计算

<正> 螺旋板换热器是一种高效节能产品,国外已有大量应用实例,其形式灵活多样。国内五十年代首先从苏联引进,六十年代开始自行设计制造,随后制定了JB1287—73《不可拆式螺旋板换热器形式、基本参数和尺寸》标准。八十年代兰石所和苏州化工机械厂共同研制开发了KLH型可拆式螺旋板换热器,并有了定点生产厂。但国内设计至今还     

乙炔清净系统节能技术改造

介绍了唐山三友氯碱有限责任公司40万t/a PVC乙炔清净系统节能技术改造方案:增加1台螺旋板换热器,将冷却塔冷却器由列管式换热器更换为螺旋板换热器。该方案实施后,每年节电180 000 kW·h,节水60 000 m3,产生的经济效益约20.3万元。     

螺旋板换热器的研究

由螺旋板换热器的几何分析出发计算了换热器的传热面积，并写出了换热器的传热方程式。     

焦油一次汽化温度计算方法的探讨

利用相平衡原理得出的焦油蒸馏时一次汽化温度的计算方法,其结果与按经验公式的计算结果进行了比较,同时讨论了一次汽化温度与焦油馏分产率及二段蒸发器过热蒸汽用量的关系。     

Techniques for screening adhesives for structural applications

—Due to its chemistry, no structural adhesive system (epoxies, acrylics, etc.) is likely to offer an ideal combination of toughness, strength, moisture resistance, and ambient-temperature curing. Therefore, for effective use of adhesives in primary structures, an engineer must be able to identify adhesives that represent an optimum compromise among the different properties. In this paper, we present techniques for screening high-strength, ambient-temperature-curing adhesives for (1) moisture resistance under sustained loading and (2) fracture resistance in a way that is directly related to joint performance.     

Efficacy for Whitlockite for Augmenting Spinal Fusion

Whitlockite (WH) is the second most abundant inorganic component of human bone, accounting for approximately 25% of bone tissue. This study investigated the role of WH in bone remodeling and formation in a mouse spinal fusion model. Specifically, morphology and composition analysis, tests of porosity and surface area, thermogravimetric analysis, an ion-release test, and a cell viability test were conducted to analyze the properties of bone substitutes. The MagOss group received WH, Group A received 100% beta-tricalcium phosphate (β-TCP), Group B received 100% hydroxyapatite (HAp), Group C received 30% HAp/70% β-TCP, and Group D received 60% HAp/40% β-TCP (n = 10 each). All mice were sacrificed 6 weeks after implantation, and micro-CT, hematoxylin and eosin (HE) staining, and Masson trichome (MT) staining and immunohistochemistry were performed. The MagOss group showed more homogeneous and smaller grains, and nanopores (<500 nm) were found in only the MagOss group. On micro-CT, the MagOss group showed larger fusion mass and better graft incorporation into the decorticate mouse spine than other groups. In the in vivo experiment with HE staining, the MagOss group showed the highest new bone area (mean: decortication group, 9.50%; A, 15.08%; B, 15.70%; C, 14.76%; D, 14.70%; MagOss, 22.69%; p < 0.0001). In MT staining, the MagOss group demonstrated the highest new bone area (mean: decortication group, 15.62%; A, 21.41%; B, 22.86%; C, 23.07%; D, 22.47%; MagOss, 26.29%; p < 0.0001). In an immunohistochemical analysis for osteocalcin, osteopontin, and CD31, the MagOss group showed a higher positive area than other groups. WH showed comparable bone conductivity to HAp and β-TCP and increased new bone formation. WH is likely to be used as an improved bone substitute with better bone conductivity than HAp and β-TCP.     

Demand Increases for New Fungicides for Rice

<正> After June this year China's regions growingmiddle and late rice had widespread blastand sheath/culm blight.Such diseasesplagued 19.2 million hectares.Starting fromJuly the market for new fungicides that cancontrol blast and sheath/culm blight for ricewas more and more active.Makers of traditional pesticides for thecontrol of blast have to contend with fiercecompetition from new pesticides in marketthis year.Kitazine,iprobenfos,isoprothiolane and tricyclazole,oftenused by farmers in the past,are graduallybeing replaced by new varieties with high