REXA执行器在主风机静叶调节系统中的应用

针对二催化主风机原电液伺服静叶调节系统存在的动力油系统泄漏严重、伺服马达拒动、伺服阀卡涩及静叶漂移等问题,对该系统进行了改造。将原电液执行器更换为REXA执行器。改造后,极大地减少了液压油管路,解决了原系统的伺服阀卡涩、静叶漂移及渗漏等问题。     

新型REXA执行器在风机静叶调节系统中的应用

针对大庆石化催化裂化主轴流风机原电液伺服静叶调节系统存在的动力油系统泄漏严重、伺服马达拒动、伺服阀卡涩及静叶漂移等问题,对该系统进行了升级改造。将原电液执行器更换为REXA电液执行器,增加REXA控制单元。系统改造后,缩短了液压油管路,原系统的伺服阀卡涩、静叶漂移及渗油漏油等问题得到很好的解决。结果表明,REXA执行器具有响应速度快、定位精度高、抗干扰能力强等优点,同时节约了人工成本。     

汽轮机电液调节系统负荷波动原因分析与处理

介绍汽轮机电液调节系统负荷波动情况及电液调节控制系统工作原理,通过加强汽轮机各调门电液DDV伺服阀和油动机内部清理等措施,彻底消除因内部滑阀卡涩导致汽轮机负荷波动的问题。     

流化床造粒机喷头故障分析与对策

重点对流化床造粒机第1室屡次出现尿素大块的原因进行分析,主要是由于前系统夹带来的杂质使喷头卡涩,影响转子正常旋转所致.研究了喷头卡涩的现象和造粒机第1室的流化情况,提出喷头维护和工艺操作的一些措施与建议,造粒机运行周期明显延长.     

汽轮机调节汽阀卡涩故障原因分析

阐述并分析了乙烯装置国产汽轮机调节汽阀的结构及特点,对汽阀卡涩的原因进行了简要的分析。结合实际工况,分析了其卡涩原因(如调节汽阀阀杆弯曲、控制油油路堵塞、错油门滑阀表面有杂质),提出了改进措施及生产运行中的注意事项。并就如何保证调节汽阀长期稳定运行,从运行操作控制、巡检、和检修等方面进行了阐述,为汽轮机的长周期稳定运行提供了参考。     

余热电站某汽轮机组油中带水的原因及处理

<正>某余热电站低温低压单缸凝汽式汽轮机型号为N6-1.5/350。机组运行时,油系统带水问题较严重,各瓦回油管视窗上带有很多水滴。油中带水对机组的安全运行造成的影响是严重的,会加剧设备锈蚀、油质恶化,造成润滑不良、钨金磨损、机组振动增大,引起调节部套卡涩、主汽阀和调节汽阀卡涩,甚至造成重大恶性事故。1轴封漏汽量分析计算1.1轴封结构及系统简介开式系统,前轴封结构由三段薄片式轴封组成。第     

壳牌气化飞灰系统阀门卡涩问题分析及改进

分析了壳牌气化工艺飞灰系统阀门卡涩的原因,从设备、顺控程序、工艺等方面进行改进,解决了飞灰系统阀门因卡涩而打不开或开不到位的问题.     

壳牌气化飞灰系统阀门卡涩问题分析及改进

分析了壳牌气化工艺飞灰系统阀门卡涩的原因,从设备、顺控程序、工艺等方面进行改进,解决了飞灰系统阀门因卡涩而打不开或开不到位的问题。     

高压蒸汽控制阀卡涩原因分析及处理措施探讨

介绍合成氨装置高压蒸汽控制阀长期存在卡涩的情况,分析造成控制阀卡涩的可能原因,采取相应处理措施,有效解决了控制阀卡涩的隐患。     

壳牌气化飞灰系统阀门卡涩问题分析及改进

分析了壳牌气化工艺飞灰系统阀门卡涩的原因,从设备﹑顺控程序﹑工艺等方面进行改进,解决了飞灰系统阀门因卡涩而打不开或开不到位的问题。     

褐煤半焦中挥发分对半焦脱灰效果的影响

以云南弥勒褐煤为原料，采用中低温干馏对褐煤进行炭化处理，使褐煤中的大部分水分和挥发分气化除去得到褐煤半焦．控制褐煤炭化条件——炭化终温、炭化时间，得到挥发分含量不同的褐煤半焦，采用絮凝法脱灰，研究半焦的脱灰效果，得到适合脱灰的合理的半焦成分．脱灰后将低灰半焦压制成型，可代替木炭作为硅冶炼还原剂，解决木炭资源缺乏的问题．     

Maerz窑两种常见热工故障的处理

窑膛A出料轻烧白云石的CO2量波动较大，发现18号和20号枪对应的喷枪隔热盖板温度超高150℃以上，该盖板对应的喷枪已经烧坏，喷枪护罩烧坏的可能性非常大。为了确定烧坏程度，停窑打开喷枪盖板进行检查，发现2#和3#喷枪烧断，对应的护罩严重烧坏，针对此问题进行研究并给出了比较安全可靠的解决方法。     

烧粘土的胶凝性能

在水泥中掺加混合材是改善混凝土耐久性能的重要措施之一。我国矿渣资源紧缺，而烧粘土型的工业废渣如粉煤灰、煅烧煤矸石和炉渣资源却相当丰富。本文探讨了这类渣的矿物组成、煅烧温度与胶凝性能的关系。     

西门子S7-300实现焦化装置水力除焦自动控制

介绍西门子S7-300PLC实现焦化装置水力除焦的自动控制,主要从水力除焦控制系统组成、控制系统工作原理、典型联锁逻辑控制、与DCS系统的通讯、除焦系统CPU之间的通讯等方面进行阐述。     

Production of Phenols and Spines in Response to Shoot Damage in Prosopis caldenia and Prosopis flexuosa

Shoot damage affects the chemical and physical defenses of woody plants. We studied how branch defoliation and intensive shoot damage affected leaf phenol concentration and spinescence in Prosopis caldenia and P. flexuosa. Individuals of both species were branch defoliated, heavily pruned, or naturally burnt. At the end of the growing season, stump (from pruned plants) and burnt sprouts, defoliated branches, and branches from intact control plants were harvested for assessment of phenols and spinescence. In both species, foliar phenol content in stump or burnt sprouts and defoliated branches were similar or below that of intact control branches. The biomass invested in spines was similar, spine length lower, and spine density higher in stump or burnt sprouts than in control branches in both species. These findings are discussed in relation to the juvenile-reversion hypothesis and the carbon/nutrient balance hypothesis.     

Behavioral and electrophysiological responses of Arhopalus tristis to burnt pine and other stimuli

The exotic longhorn beetle Arhopalus tristisis a pest of pines, particularly those damaged by fire, and a major export quarantine issue in New Zealand. Actinograph recordings of caged individuals showed that males and females were most active from dusk to midnight. Olfactometer experiments indicated that females moved upwind toward odors from burnt pine (80%, N= 75), compared to unburnt pine (20%). Oviposition choice tests showed that eggs were predominantly laid on burnt logs (79%, N= 20), compared to unburnt logs. Beetles were trapped by funnel traps baited with burnt (mean catch per trap 7.8) and unburnt (mean catch 4.1 per trap) pine bark from inside a screen cage (4 × 3 m), while unbaited traps had a mean catch 0.1 beetles (N= 8 replicates). The treatment of burnt pine bark with a 1:1:2 mixture of green leaf volatiles (E)-2-hexen-1-ol and (E)-2-hexenal) in mineral oil as a repellent reduced trap catch by fivefold in a similar experiment (mean catches of 1.2 beetles per trap to burnt pine bark plus repellent treatment and 6.2 beetles per trap to burnt pine bark alone). The treatment of burnt pine bark with this solution also reduced oviposition by 98.5% (mean eggs per log of 11.1 on burnt pine and 0.3 on burnt pine plus repellent), indicating that oviposition cues have the potential to be significantly disrupted. The electrophysiological responses of adult beetles were recorded to a range of odorants. Normalized responses to monoterpenes known to occur in Pinus radiataranged from about 20 to about 150, with -terpineol giving the greatest responses in both sexes. Green leaf volatiles also gave high responses. The potential exists to improve the management of this insect using chemical cues in various ways.     

Emulation and Calculation of the Burning Surface of 3D Grains of Partially Cut Multi‐Perforated Stick Propellant using the Level Set Method

In order to calculate the burnt mass fraction of complex three‐dimensional (3D) propellant grains to meet the requirements of interior ballistic modelling; the level set method is introduced to emulate and calculate the burning surface area of partially cut 7‐perforated propellant. The surface evolution and simulation of a 3D grain of partially cut 7‐perforated propellant are divided into two parts: the grain configuration initialization and the level set calculation of the propellant regression process. Parallel layer burning is assumed so that the burning surface regresses layer by layer in a direction normal to the surface until the grain is burnt completely. As the burnt mass fraction increases, the remaining propellant volume decreases gradually. The level set method easily simulates the slivering process for complex grain geometries. In this way, the burnt mass fraction of partially cut 7‐perforated propellant grain can be calculated by the level set method for the entire combustion process. Results show that the level set method is suitable to capture the burning surface for each burning step and its related parameters, such as the burning area, the remaining propellant volume and burnt mass fraction. More importantly, the level set method gives a possible solution to the coupling of grain combustion with the internal fluid simulation by the pressure and velocity. It is impossible for geometry‐based methods to integrate the internal fluid parameters in an interior ballistic model. Also, the level set method will benefit substantially the grain design and lead to improved internal ballistic performance.     

内蒙乌海煤矸石循环流化床燃烧试验研究

针对设计煤、校核煤及石灰石在1MWth循环流化床燃烧(CFBC)试验台上的燃烧试验研究结果进行分析总结。取得了内蒙乌海煤矸石采用CFB燃烧方式时的大量重要的技术数据,可为京煤集团有限责任公司的CFB锅炉设计和锅炉岛系统设计提供基础数据和设计依据。     

焦炉燃烧废气含氧量检测系统

介绍了焦炉燃烧废气含氧量检测系统,该系统分别对多个蓄热室小烟道处的燃烧废气取样,用1台氧化锆氧量分析仪检测燃烧废气的含氧量。在自动模式下,能在1个换向周期内完成多个下降气流的蓄热室含氧量的自动检测;在手动模式下,又能对单个蓄热室进行连续检测。系统检测精度高、实时性强、投资成本低、维护量少,为判断焦炉各燃烧室的燃烧状况提供了检测依据。     

煅烧石膏对粉煤灰—石灰体系火山灰反应的影响

本文研究了煅烧石膏的溶解特性 ,用结合水量、Ca(OH) 2 量和粉煤灰的反应率的测定 ,证明煅烧石膏加速了粉煤灰 -石灰的火山灰反应 ,并阐明了机理。