螺杆式制冷压缩机及其应用

一、螺杆式制冷压缩机的发展及其特点螺杆式制冷压缩机早在1878年已经问世,但没有实用意义。直到1934年瑞典科学家重新进行研制,并获得成功。1963年发明了第一台喷油螺杆式制冷压缩机。同年荷兰某肉类冷库已开始应用这种新型机器。欧美、日等工业发达国家已率先将螺杆式制冷压缩机应用于陆用或船用的冷库制冷系统、空调系统、工业制冷装置等。许多生产厂家为了提高螺杆效率及降低其噪音方面,进行新的转子型线及其它方面的研究和试验。     

高效螺杆式CO2制冷压缩机的优化设计

在对螺杆式CO2制冷压缩机的转子进行优化的基础上,对相应的壳体强度、轴承选择、油路布置等进行优化设计,根据优化设计参数制造螺杆式CO2制冷压缩机样机并进行测试。试验结果表明,优化设计后的螺杆式CO2制冷压缩机具有很高的效率及可靠性。     

变频螺杆式制冷压缩机的应用现状及研究进展

变频技术作为一种容积流量调节方式,具有调节范围大、结构简单、启动电流平稳等优点,越来越多地应用于螺杆式制冷压缩机。本文从产品的角度介绍变频螺杆式制冷压缩机的应用现状,并从变频技术、压缩机性能预测、控制优化、电机及变频器的冷却、噪声与振动以及油路优化等方面介绍变频螺杆式制冷压缩机的研究进展,最后阐明变频螺杆式制冷压缩机的未来发展趋势。     

螺杆式制冷机在渔船上应用的远景

一、绪论目前在我国自己建造的带有制冷装置的渔船上还很少有安装螺杆式制冷机的,特别是在捕鱼的作业船上几乎没有,基本上都是使用活塞式制冷机。螺杆式制冷机属于容积式回转压缩机,它是由一对相互啮合的螺轩转子的回转运动代替活塞式制冷机活塞的往复运动。阴转子的齿沟相当于气缸,阳转子的齿相当于活塞,由     

螺杆式氨制冷压缩机油压低问题试验分析

螺杆式氨制冷压缩机在低温工况时出现供油压力低问题,这是一个比较普遍的现象.本文通过分析螺杆式制冷压缩机试验结果,求得螺杆式制冷压缩机供油压力低问题的根源.     

螺杆式制冷压缩机油压低问题试验分析

螺杆式制冷压缩机在低温工况时出现供油压力低问题,这是一个比较普遍的现象,本文通过分析螺杆式制冷压缩机试验结果,分析了螺杆式制冷压缩机供油压力低问题的根源,得出试验结构。     

活塞式与螺杆式制冷压缩机的选型设计

本文通过活塞式制冷压缩机和螺杆式制冷压缩机在几方面的比较分析 ,结合设备各自存在的特点 ,以及对新老用户的选型建议 ,为设计和使用单位在选取制冷压缩机时提供了理论参考。     

低温用半封闭螺杆式压缩机的现状及发展趋势

低温用半封闭螺杆式压缩机因其高效紧凑等优势正逐渐取代其他形式的压缩机,成为冷冻冷藏用压缩机的首选。本文介绍低温螺杆式压缩机的应用场合以及国内外低温用半封闭螺杆式压缩机的主要生产厂商,并结合产品从转子型线、电机冷却、容量调节、制冷剂的使用等方面阐述目前低温用半封闭螺杆式压缩机的发展现状及趋势。     

NH_3螺杆式全热回收高温热泵系统研究

介绍NH_3作为热泵工质的主要特点,分析NH3螺杆式全热回收高温热泵系统的应用形式及原理。针对高温热泵用NH_3螺杆式压缩机的特点,开发出适用于该压缩机的螺杆转子型线,同时采用内容积比可调技术对压缩机性能进行优化。试验结果表明,系统可在出水温度87℃时可靠运行。并阐述系统设计相关结论,供行业研究人员参考。     

螺杆式制冷压缩机转子型线优化设计

前言六十年代以来,螺杆式压缩机以其可靠性高、结构简单、体积小、重量轻、易损件少、运转平稳以及可以带液压缩等明显的优点,在大冷量范围内逐步取代活塞式压缩机,然而就我国目前情况来看,螺杆式制冷压缩机还存在着效率偏低、噪音及振动偏大等缺点,急待作进一步的改进。     

浅谈半封闭单机双级螺杆压缩机在食品冷藏链中的节能优势

本文以“复盛”低温半封闭单机双级螺杆压缩机为例,对单级螺杆式压缩机与单机双级压缩机各自的应用范围及性能比较,揭示了在R22与R404A制冷系统中,蒸发温度低于．30℃时带经济器的单机双级螺杆式压缩机组在食品冷藏链制冷系统中的制冷量、制冷效果上有着明显的节能优势,有广泛的市场应用前景。     

Theoretical and experimental research on the working process of screw refrigeration compressor under superfeed condition

In order to increase the refrigeration capacity and improve the coefficient of performance (COP), an economizer arrangement is used in the refrigeration system with screw refrigeration compressor. In this system, the mid-pressure refrigerant gas from the economizer is injected in the screw refrigeration compressor. So it affects the performance of the compressor. In this paper, the working process of a twin screw refrigeration compressor with economizer under different superfeed pressures is studied. A mathematical model for simulating the working process of screw refrigeration compressor under superfeed condition with the economizer is presented; especially the flow coefficient of superfeed is obtained by the experimental research. To verify the model, the p–V diagrams (pressure–volume diagrams) of screw refrigeration compressor under different superfeed pressures with the economizer are recorded successfully by making use of a micro-type pressure sensor that embedded into the groove at the root of the female rotor on the discharge side. The p–V diagrams of theoretical calculation are in good agreement with the results of experimental recorded, which lead to conclusion that the model can be used as a powerful tool for performance prediction of screw refrigeration compressor, also, it is very helpful for refrigeration system design.     

Theoretical and experimental investigation on the performance of screw refrigeration compressor under part-load conditions

Slide valve is normally employed in screw refrigeration compressor to meet the cooling capacity demanded by the load variation. A mathematical model describing the working process of screw refrigeration compressor with a slide valve assembly under part-load conditions is established based on the calculation of the effective by-pass area and radial discharge area. Experimental investigation on a screw refrigeration compressor under part-load conditions with several evaporation and condensation temperatures is also carried out. Simulation results are in good agreement with the experimental ones. With the validated model, effects of key design parameters, i.e. the installation angles of the slide valve relative to the cylinder and the slide stop length, on the working process and performance of screw refrigeration compressor have been analyzed. These results can be useful for optimum design of the slide valve assembly to improve the energy efficiency of refrigeration system with screw compressor under part-load conditions.     

R22与R404A在制冷螺杆压缩机中应用的性能对比分析

本文将R22和R404A应用在制冷螺杆压缩机中的制冷特性进行了研究,对比分析了两种制冷剂应用在螺杆压缩机中的制冷量、功耗、COP、排气温度及其所需内容积比的差异。结果表明,在一定冷凝温度下,蒸发温度从．50℃～10℃之间变化时,与R22相比,R404A的制冷量和COP有所降低,功耗增加7．0％～14．7％左右,系统压比和所需的内容积比的差异小,因此在制冷螺杆压缩机中分别应用R404A和R22制冷剂时,不必改变螺杆压缩机的内容积比大小。再又,R404A在系统含水量、清洁度、密封性、冷冻油的使用方面与R22有所不同,在生产和应用中需要加以注意。     

Les hélico compresseurs ou compresseurs à visHelical or screw compressors

In the first part of the paper the patenting of the helical compressor at the end of the last century by a Swedish engineer as a type of air and gas blower, modified some 50 years later by another Swedish engineer as an air and gas compressor, is discussed. Decade by decade, the machine was developed by the Swedish firm SRM and by their licenced manufacturers machining the screw compressor in Sweden, Germany, France, Scotland, etc. At the present time this type of compressor seems to be fully developed and occupies a first class position in the range of positive displacement machines.Recently, a new type of screw compressor has been patented by a French engineer, this machine having only one main rotor and two small satellites, compared with the early type which had only two main rotors. These two types of compressors are now competing on the refrigeration market all over the world.In the second part of the paper, all the improvements made during the 50 yeats of development are examined in detail. In the beginning, the screw compressor was designed as an oil free compressor and was not very well adapted to the refrigerating plants, this type of oil free compressor still being used for the compression of pure gases. The first improvement was the oil injected screw compressor allowing the machine to support high compression ratios and large pressure differences and some time later, to be fitted with a sliding valve for the purpose of volume adaptation. One other modification to the profile of the rotors results in greater compressor efficiency allowing it to work with higher compression ratios; for example, in the case of low temperatures such as are used for the freezing of food products.This is not a good solution for saving energy, and the performance has been improved by creating a complementary orifice designed as a superfeed port. This increases the global efficiency of the whole circuit with a screw compressor.The same improvements were carried out on the mono rotor screw compressors and now the two types of compressors are competing with the same auxiliaries imposed by the special lubrication of this type of machine. Some comparisons are made with reciprocating and centrifugal compressors.     

Development of a highly reliable helium refrigeration system––R&D of a highly reliable helium refrigeration system (oil-free type)

The present paper reports the development of the highly reliable refrigeration system (three types), which is applied for 70 MW class superconducting generators. R&D of the oil-free turbo type: In the turbo type of advanced refrigeration system, a complete oil free 80 K cold compressor was developed. Moreover, the cold compressor driven by a coaxial turbine was developed to enhance the system efficiency and to save space. R&D of the oil-free screw type: In the oil-free screw rotors, taper rotors were planned to maintain a radial clearance between male and female rotors and the casing, to compensate their thermal deformation because of the heat of compression. Moreover, a seal technique was established that used a magnetic fluid and gas seals to prevent lubricating oil from bearings and the timing gear chamber into the rotor housing, under a higher rotational speed of 25,000 rpm.     

降低双螺杆制冷压缩机组噪声和振动的实验研究

为改善运行环境并提高运行性能,对一台双螺杆制冷压缩机组进行了噪声和振动实验测试。通过频谱分析发现,机组在压缩机基频整数倍的频率处出现较高的噪音和较大的振动,说明压缩机是机组主要的振动源和噪声源。通过对改进前后的压缩机组进行实验对比,分析了实验数据,提出了相应的降噪减振措施。结果表明:改进转子型线设计,调整阴、阳转子啮合间隙分布,提高阴、阳转子的加工精度等措施是机组降噪减振的有效方法。     

螺杆式制冷机组运行初始阶段油温控制分析及改进

对螺杆式制冷机组运行初始阶段的油温控制特点进行分析,发现开机时过低的冷冻油温度会使其溶解制冷剂的能力增强,从而使冷冻油黏度和润滑能力降低,加速螺杆式压缩机运动部件的机械磨损。而目前使用热力膨胀阀的油冷却系统会使供油温度不断大幅波动,并超出使用范围。采用带有加热器的油气分离器,并通过PLC控制器利用PID调节方式对电子膨胀阀开度进行自动调节,从而控制冷冻油温度,可使上述问题得到解决。     

A review of linear compressors for refrigeration

Linear compressor has no crank mechanism compared with conventional reciprocating compressor. This allows higher efficiency, oil-free operation, lower cost and smaller size when linear compressors are used for vapour compression refrigeration (VCR) system. Typically, a linear compressor consists of a linear motor (connected to a piston) and suspension springs, operated at resonant frequency. This paper presents a review of linear compressors for refrigeration system. Different designs and modelling of linear compressors for both domestic refrigeration and electronics cooling (miniature VCR system) are discussed. Key characteristics of linear compressor are also described, including motor type, compressor loss, piston sensing and control, piston drift and resonance. The challenges associated with the linear compressors are also discussed to provide a comprehensive review of the technology for research and development in future.     

用于低温复叠式制冷的CO2螺杆式压缩机组的性能实验

CO2在冷冻冷藏系统中适宜作为低温级制冷剂与其他制冷剂组成复叠式制冷循环。建立采用螺杆式压缩机组的NH3/CO2复叠式制冷实验系统,对低温级的CO2螺杆式压缩机组进行性能测试,并对主要技术参数进行分析,给出机组制冷量、轴功率、容积效率和绝热效率等在不同工况下的变化关系。在相同工况下CO2制冷机组的制冷量约是同型号氨机组的7.5～10.5倍,且在蒸发温度越低时差值越大。对NH3/CO2复叠式制冷机组和NH3单机双级压缩制冷机组的性能系数进行比较,前者在蒸发温度低于-40℃时性能系数更高。