PROFIBUS在起停式飞剪电控系统中的应用

介绍了PROFIBUS现场总线技术在起停式飞剪电控系统中的应用。分析了起停式飞剪电控系统的功能和特点，说明了PROFIBUS网的通讯原理，给出了系统的通讯网络拓扑图以及实现通讯的方法。     

热轧移动式横切飞剪的开发与仿真

介绍了全新开发的移动式横切飞剪机组组成及设计特点,并对飞剪本体下刀架的运动特点和剪机剪切过程的动力学特性分别进行了仿真分析。仿真分析和结果为后续电控系统开发及研究提供了指导和基础数据。     

飞剪飞轮矩理论计算的初步探讨

本文从电控飞剪制造的角度,依据最短定尺限制的原理,介绍了飞剪飞轮矩的理论计算。     

ASP热连轧机鼓式飞剪控制原理分析

鞍钢热轧带钢厂的鼓式飞剪是从德国引进的。针对其中的电控系统进行了分析，重点是系统的组成及设计思想等．消化吸收了引进技术。     

天津轧钢三厂棒材轧线国产化飞剪控制系统

天津轧钢三厂小型车间的整个棒材生产线所用的３台飞剪均为起停式飞剪 ,其中１#、２#飞剪为国产机电设备 ,主要作用是切头、切尾及事故碎断 ,２台飞剪的正常运行与否对棒材的成材率、轧件的顺利咬入、防止及处理生产事故等都有重要的影响。飞剪的电控系统采用美国通用电气公司的ＧＥ９０ ３０ＰＬＣ及德国西门子６ＲＡ２４直流驱动系统 ,这两种设备性能先进、可靠 ,易于实现精确控制。１硬件构成及剪切动作执行过程１ １系统硬件构成天津轧钢三厂１#、２#飞剪均为电机直接驱动型起停式飞剪 ,控制系统硬件设置如图１所示图１飞剪控制系统硬件…     

1700热连轧机鼓式飞剪电控系统分析

鞍钢半连轧机厂的鼓式飞剪是从德国引进的，针对其中的电控系统进行了分析，重点是系统组成及设计思想等，对引进技术的消化吸收有一定意义。     

倍尺剪控制系统的设计及应用

本文详细介绍了倍尺剪电控系统的构成及控制技术.选用将T400工艺板直接装入直流SIMOREG DCMASTER驱动装置中这种控制结构,可以满足飞剪高速运算、高速反应的要求.     

小型全连轧改造精整工段电控系统

轧三半连轧改造后,冷床上钢动作由电控系统发出信号控制电机来完成,不能满足高速生产要求,在全连轧改造中,采用电控系统控制液压缸来完成上钢动作,适应了16m/s轧制速度要求,解决了飞剪至冷床距离短的问题,满足了生产工艺要求,提高了产量,取得了经济效益。     

数字化技术在曲柄起停式飞剪上的应用

为了解决曲柄起停式飞剪原有模拟控制系统存在的问题,在技术改造中采用了由西门子公司可编程控制器S7-300和直流传动装置以6RA70以及工业现场总线PR0FIBUS-DP联网组成的全数字电控系统.采用了全数字电控系统后,设备作业率提高,工艺性能改善,维护量显著降低,充分显示出模拟系统的数字化是设备改造与技术创新的方向.     

1400mm铝带飞剪电控系统

本文主要介绍1400mm铝带飞剪机组电控系统的系统组成、系统硬件、软件设计和主要控制思想。该系统采用DCS500B全数字直流传动模块、S7－300程控器及FM350－1高速计数模块。     

用轴向气胎式离合器,制动器改造旧飞剪

采用轴向式气胎离合、制动器，改造了旧飞剪，解决了原剪机电磁离合、制动器控制不准确的问题；该剪机改造后在成品轧机后使用，剪切用１２０ｍｍ×１２０ｍｍ坯生产的大规格产品（１８ｍｍ以上），增产、增效，年总经济效益为９７．８万元     

2250横切飞剪剪切长度异常原因分析及对策

通过长期的观察和分析,针对2 250横切飞剪在生产过程中出现的剪切长度异常现象,总结出了钢板出现剪切长度异常的各种原因。从2 250横切飞剪的控制系统入手,提出了一种解决剪切长度异常的方案;通过测量辊和夹送辊之间的差值,判别是否出现剪切长度异常并及时通知操作人员。通过实际生产应用证明了该方案的可行性,该方案的应用大幅度提高了钢板剪切的成材率,避免由于飞剪剪切异常而造成的经济损失。     

新型摆动式分段圆盘飞剪的结构与分析

文章介绍了新型摆动式分段圆盘飞剪的工作原理与结构，与下轴浮动式圆盘飞剪相比，该新型剪机的结构简单，受力合理，刚度及剪刃寿命提高，且维修方便     

移动式飞剪定尺故障的分析

分析了移动式飞剪机构及控制剪切原理,总结出了制约其定尺不准的几大因素,并据此采取了一些措施,为彻底解决飞剪定尺不准提供了确实的依据,以利于今后提高剪切质量及对飞剪进行升级改造提供了方向。     

Strength Characteristics of Class F Fly Ash Modified with Lime and Gypsum

This paper presents the shear strength characteristics of a low lime class F fly ash modified with lime alone or in combination with gypsum. Unconfined compression tests were conducted for both unsoaked and soaked specimens cured up to 90 days. Addition of a small percentage of gypsum (0.5 and 1.0%) along with lime (4–10%) enhanced the shear strength of modified fly ash within short curing periods (7 and 28 days). The gain in unsoaked unconfined compressive strength (qu) of the fly ash was 2,853 and 3,567% at 28 and 90 days curing, respectively, for addition of 10% lime along with 1% gypsum to the fly ash. The effect of 24?h soaking showed reduction of qu varying from 30 to 2% depending on mix proportions and curing period. Unconsolidated undrained triaxial tests with pore-pressure measurements were conducted for 7 and 28 days cured specimens. The cohesion of the Class F fly ash increased up to 3,150% with addition of 10% lime along with 1% gypsum to the fly ash and cured for 28 days. The modified fly ash shows the values of Skempton’s pore-pressure parameter, Af similar to that of over consolidated soils. The effects of lime content, gypsum content, and curing period on the shear strength parameters of the fly ash are highlighted herein. Empirical relationships are proposed to estimate the design parameters like deviatoric stress at failure, and cohesion of the modified fly ash. Thus, this modified fly ash with considerable shear strength may find potential use in civil engineering construction fields.     

Effect of Fly Ash on Engineering Properties of Expansive Soils

This note presents a study of the efficacy of fly ash as an additive in improving the engineering characteristics of expansive soils. An experimental program has evaluated the effect of the fly ash content on the free swell index, swell potential, swelling pressure, plasticity, compaction, strength, and hydraulic conductivity characteristics of expansive soil. The plasticity, hydraulic conductivity and swelling properties of the blends decreased and the dry unit weight and strength increased with an increase in fly ash content. The resistance to penetration of the blends increased significantly with an increase in fly ash content for a given water content. Excellent correlation was obtained between the measured and predicted undrained shear strengths.     

连轧厂粗轧机后切头飞剪的改型与设计

介绍了长钢连轧厂粗轧机后切头飞剪的改进,选型设计及其启停式飞剪的使用效果和特点。     

Time Effect on Shear Strength and Permeability of Fly Ash

This paper investigates the effect of time on the shear strength and the permeability of fly ash, a major solid by-product of thermoelectric power plants. Direct shear tests using Mikasa's apparatus, conventional permeability tests, and consolidation tests were conducted on two silt-size fly ashes, with low free lime contents, obtained from two different power plants. The results show that the immediate settling of both fly ashes takes place in a short period of time during consolidation and does not change with time. The rate of increase in shear strength with time is different depending on the pozzolanic reactions taking place for the two ashes. The permeability tests under constant stresses of 49 and 98 kPa for 12 days show that the coefficient of permeability for the tested ashes is between 10?6 and 10?7 m∕s. During this period the coefficient of permeability either remains constant (for the case of the ash with a lower free lime content) or is slightly reduced (for the ash with a higher free lime content). The practical implications and the limitations of using low lime silt-size fly ash in vertical drains in the stabilization of soft ground are also discussed.     

新型防雷及抗干扰方法在电铲控制系统的应用

电铲是采区主要采掘设备,其弱电控制系统是电铲正常可靠运行的关键。由于雷击或电磁干扰造成弱电控制系统装置的损坏或工作异常等故障,已成为影响电铲安全正常运行的重要因素。针对现有电铲控制系统防雷抗干扰现状、存在的问题及影响,研究了一种新型防雷抗干扰方法,并分析了其在电铲弱电控制系统中的应用和实施效果。实际运行表明,新型防雷抗干扰方法能够有效提高电铲弱电控制系统防雷及抗干扰能力,对电铲及其他弱电控制系统防雷抗干扰的研究和应用具有积极的现实意义,且有着很好的推广价值。