Unit 19 Types of Heat Exchangers 1
1 Unit 19 Types of Heat Exchangers
管口表 液进如 莱出口 液进知 d #污和 琴气口 B明 举污日 L L5 9 液出自 Lo h 气口 2
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每 text Heat exchangers are equipment primarily for transferring heat between hot and cold streams.They have separate passages for the two streams and operate continuously.The most versatile and widely used exchangers are the shell-and tube types,but various plate and other types are valuable and economically or superior in some applications. 3
3 text 1-1 Heat exchangers are equipment primarily for transferring heat between hot and cold streams. They have separate passages for the two streams and operate continuously. The most versatile and widely used exchangers are the shell-andtube types, but various plate and other types are valuable and economically or superior in some applications
1-2 These other types will be discussed briefly,but most of the space following will be devoted to the shell-and-tube types, primarily because of their importance,but also because the are most completely documented in the literature.Thus the can be designed with a degree of confidence to fit into a process.The other types are proprietary and for the most pa must be process designed by their manufacturers. 4
4 1-2 These other types will be discussed briefly, but most of the space following will be devoted to the shell-and-tube types, primarily because of their importance, but also because they are most completely documented in the literature. Thus they can be designed with a degree of confidence to fit into a process. The other types are proprietary and for the most part must be process designed by their manufacturers
换热器是主要用于冷热流束间传递热量的设备.对于两种流体而言， 具有单独的通道，并且连续操作功能最多，且广泛使用的换热器是管 壳式换热器，但各种板式及其他类型的换热器也有其价值，在某些使 用中具有经济性和优势这些其他类型的换热器将概括讨论，而接下 来的大部分篇幅将涉及管壳式的，主要因为他们即重要，又因为在文 献中他们大部分具有最完整的记录.于是我们就有信心设计出与过 程相匹配的管壳式换热器.其他形式的换热器是带有专利性的，且大 部分必须由他们制造商进行工艺设计. 5
5 1 换热器是主要用于冷热流束间传递热量的设备.对于两种流体而言, 具有单独的通道,并且连续操作.功能最多,且广泛使用的换热器是管 壳式换热器,但各种板式及其他类型的换热器也有其价值, 在某些使 用中具有经济性和优势.这些其他类型的换热器将概括讨论,而接下 来的大部分篇幅将涉及管壳式的, 主要因为他们即重要,又因为在文 献中他们大部分具有最完整的记录.于是我们就有信心设计出与过 程相匹配的管壳式换热器.其他形式的换热器是带有专利性的,且大 部分必须由他们制造商进行工艺设计
2 Plate-and-frame exchanger Plate-and-frame exchangers are assemblies of pressed corrugated plates on a frame.Gaskets in grooves around the periphery contain the fluid and direct the flows into and out of the space between the plates.Close spacing and the presence of the corrugations results in high coefficients on both sides several times those of shell-and-tube equipment and fouling factors are low. 6
6 2-1 Plate-and-frame exchanger Plate-and-frame exchangers are assemblies of pressed corrugated plates on a frame. Gaskets in grooves around the periphery contain the fluid and direct the flows into and out of the space between the plates. Close spacing and the presence of the corrugations results in high coefficients on both sides several times those of shell-and-tube equipment and fouling factors are low
上导杆 活动压紧板 固定螺丝 前支杆 固定压紧板 下导杆 火紧螺杆 板片及垫月 支烟 7
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The accessibility of the heat exchanger surface for cleaning makes them particularly suitable for fouling services and a high degree of sanitation is required,as in food and pharmaceutical processing.Operating pressures and temperatures are limited by the natures of the available gasketing materials,with usual maxima of 300 psi and 400 8
8 2-2 The accessibility of the heat exchanger surface for cleaning makes them particularly suitable for fouling services and a high degree of sanitation is required, as in food and pharmaceutical processing. Operating pressures and temperatures are limited by the natures of the available gasketing materials, with usual maxima of 300 psi and 400 °
板框式换热器 板框式换热器是由压制成型的波纹板组装在一框架上而形成的薇压成波 敏状的板子安装在框架上组装成的，.在周边槽里的垫片对流体起密封作用并引导流体 进出板间的空隙密闭的空隙和波纹的存在使两边具有很高的传热 系数，是管壳式设备的几倍，并且污垢系数低.换热器表面可以清洗，使 得板框式换热器特别适合于易结垢和卫生要求高的场合，如在食品 及制药工艺中操作压力和操作温度受到可用垫片材料特性的限制， 通常最大为300psi和400°F. 9
9 2 板框式换热器 板框式换热器是由压制成型的波纹板组装在一框架上而形成的(被压成波 纹状的板子安装在框架上组装成的.).在周边槽里的垫片对流体起密封作用并引导流体 进出板间的空隙.密闭的空隙和波纹的存在使两边具有很高的传热 系数,是管壳式设备的几倍,并且污垢系数低.换热器表面可以清洗,使 得板框式换热器特别适合于易结垢和卫生要求高的场合,如在食品 及制药工艺中.操作压力和操作温度受到可用垫片材料特性的限制, 通常最大为300psi和400°F
3 Since plate-and-frame exchangers are made by comparative few concerns,most process design information about them i proprietary but may be made available to serious engineers Fraction factors and heat transfer coefficients vary with the plate spacing and the kinds of corrugations.Pumping costs per unit of heat transfer are said to be lower than for shell- and-tube equipment.In stainless steel construction,the plate-and-frame construction cost is 50%~70%that of shell-and-tube. 10
10 3 Since plate-and-frame exchangers are made by comparatively few concerns, most process design information about them is proprietary but may be made available to serious engineers. Fraction factors and heat transfer coefficients vary with the plate spacing and the kinds of corrugations. Pumping costs per unit of heat transfer are said to be lower than for shelland-tube equipment. In stainless steel construction, the plate-and-frame construction cost is 50% ~ 70% that of shell-and-tube