柴油机调速器常见故障与修理方法

调速器是柴油机的重要组成部分,分析了柴油机几种常见故障与调速器的关系,对产生故障的原因进行了初步探讨,介绍了调速器主要零件常用修理方法。     

柴油机常见故障与调速器的关系

调速器是柴油机的重要组成部分。基于柴油机调速器的先进性、精密性和复杂性,调速器故障成了柴油机的典型疑难故障。为此,以PGA型柴油机调速器为例,简要说明了PGA型柴油机调速器的组成及工作原理,分析了柴油机几种常见故障与调速器的关系,对产生故障的原因进行了初步探讨,提出了一些排除调速器常见故障的方法。     

喷油泵及调速器常见故障分析

燃油系统的技术状态如何,对柴油机的动力性和经济性有直接影响。燃油系如果有故障,就会造成柴油机工作出现相应的故障。下面就喷油泵及调速器总成的常见故障加以分析,供参考。     

调速器为什么会失灵

调速器在柴油机上随负荷变化而自动改变喷油泵供油量，使柴油机在其预定的转速范围内稳定运转。一旦调速器发生故障，其调速功能丧失，柴油机便不能正常运转。调速器失灵的常见现象及原因如下：     

Ⅱ号喷油泵调速器总成几个常见故障的原因分析

调速器在结构上与喷油泵装在一起,组成一个总成,叫做“喷油泵调速器总成”。本文对Ⅱ号喷油泵调速器总成的几个常见故障进行分析。总成的故障固然可以从其本身上反映出来,但很多情况下,只是在装上柴油机并运转后,从柴油机的异常现象中才被人们发现。1柴油机启动困难柴油机启动困难的原因很多,如果仅就Ⅱ号喷油泵调速器总成来进行分析,以下几个原因应给予特别的注意。(1)试验表明,Ⅱ号喷油泵上体油道压力低于60kPa时,柴油机启动困难。由此可见,喷油泵回油阀不严密是导致柴油机启动困难的重要原困之一。(2)启动油量不足、启动弹簧过软以及低…     

柴油机转速不稳原因分析与排除

柴油机在运转过程中，不能随负荷的变化自动调节循环供油量，发生转速忽高忽低，不能稳定运转的故障，俗称“游车”或“喘车”。出现此种故障，轻者柴油机不能正常工作，作业效率和作业质量降低，难以操纵；重者会使柴油机在负荷重时造成停车。柴油机“游车”的原因主要在供油系统，应从以下几方面进行检查排除。调速器故障柴油机发生“游车”故障，调速器工作不正常是最为常见的原因。造成调速器工作不正常的原因主要有：(1)调速弹簧弹力减弱。调速弹簧弹力不足时，在柴油机负荷增加、转速降低的情况下，调速弹簧弹力不足以推动喷油拉杆向…     

柴油机飞车的原因及排除

柴油机的飞车是指柴油机转速失去控制,转速越来越高的故障。飞车会造成柴油机杵缸、断轴等重大事故。柴油机一般是在刚启动或工作中负荷突然消失或减轻的时候才会出现飞车故障,而在负荷下工作,不会发生飞车故障。发生飞车的原因有:1.调速器壳内润滑油加得过多,影响了调速作用;调速器摩擦离合器打滑;调速器高速限制螺钉和安全档松动;飞快脱出或卡滞;调速弹簧拆断、推力轴承或调速器轴承损坏,使调速器失灵,造成飞车。2.单缸柴油机的单体喷油泵调速器传动滑套卡住,造成调速失灵,出现飞车故障。3.喷油泵柱塞偶件因安装歪斜或油污卡住,不能转动,…     

离心式调速器的分类及工作原理

喷油泵调速器是一种自动调节喷油泵供油量大小的装置,它可使柴油机喷油泵以较稳定的转速进行运转,从而保证柴油机既不会产生超速也不会在怠速时停止运转。本文详细地讲述了柴油机离心式调速器的分类及工作原理。     

调速器常见故障检修

调速器一般由飞块组合件，调速弹簧和操纵机构组成，它是根据柴油机的负荷变化，自动地调节喷油泵的供油量，以保证柴油机在各种工况下稳定地运转。车用柴油机多采用机械离心式两极调速器，它能自动控制发动机额定最高转速（2800r / mi n）和怠速稳定转速。发动机在怠速与额定转速之间的转速范围内工作时，两极调速器不起调节作用，而是靠驾驶员控制油量来改变发动机转速，使用中调速器常会发生调速不当，使之控制转速与实际不符；运动件因磨损而松旷，调速弹簧失去作用或运动件锈蚀发卡及调速器内润滑油过多，粘度过大（滑油不符合要求）等…     

燃油泵及调速器的常见故障分析

燃油系统的技术状态如何,对柴油机的起动性能、动力性和经济性有直接影响,燃油系如果有故障,将会造成柴油机工作出现相应的故障现象。现就燃油泵及调速器总成的常见故障加以分析,供参考。一、供油量不均匀、不稳定此故障的原因有:出油阀锥形密封面磨损,使其密封性能不良;油路有空气(可通过排除空气来解决);输油泵供油压力不足(应检查输油泵的进出油阀门、滤清器和调     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。