利用PDMS软件三维设计平台进行配管加工设计新方法探讨

在配管加工设计中,抽取管线ISO图是一项耗时长、工作量大的工作。为了保障该项工作效果,本文就PDMS软件三维设计平台配管加工设计进行了一定的研究。     

三维软件管道设计在化工领域的应用

化学工程的管道设计工艺对配管精度要求高、质量要求严。为了满足复杂环境下的化工管道的设计工作,在传统的二维AutoCAD、ISO管线图的基础上,利用计算机三维仿真建模技术替代手工设计,极大提高了管线设计的效率和精确度,提供了化工管线设计的整体解决方案,提升了投资效益。     

在化工配管设计中应用三维软件—PDS

PDS在化工管道设计领域中的应用日益广泛,本文介绍PDS的功能结构模块及其衍生的用于检查的辅助工具软件"Smart Plant Review";PDS数据库的相关内容:数据库的结构、数据库的建立及数据库的管理与备份;同时介绍如何利用PDS进行化工管道三维模型设计及其设计产品文件:ISO图、管道平面布置图和材料报告。     

工厂三维布置设计管理系统——PDMS

结合PDMS在南京杭氧气体有限公司30000m3/h空分设备项目的使用情况,系统地介绍了利用PDMS软件在空分设备配管设计过程中的具体应用,建立PDMS管道数据库、建立管道、设备的三维模型及管线ISO图、平面图的抽取;并提出了PDMS软件的应用体会,对PDMS软件的进一步深入应用进行探讨。     

海上采气井口排液采气安装管线设计

根据埕岛CBG5采气井口存在着产水过多的问题,提出了根据现场实际情况设计的解决方案,介绍了安装管线所采取的加工工艺措施。阐述了该管线各部件的功能及整个管线排液采气的工作原理。     

EYECAD三维配管软件在日本工程中的应用

以污水污泥处理工程设计为例,介绍了EYECAD三维配管软件应用经验和过程.EYECAD能生成可靠的ISO图纸、平剖图以及精确的材料表、工艺管线规格表等.     

一种海洋钢结构三维加工设计新策略

在海洋钢结构加工设计工作中,要进行单件图、加设图、布置图、材料清单、吊装、应力计算报告等工作,通常这些工作都是由多种工具共同完成的。本文介绍了一种全过程集中处理上述工作的方法,只利用一种三维设计工具,独立完成以上全部工作。借鉴三维设计的思路,综合运用二次开发,参数化建模和模拟全过程施工的方法,提出一种一体化的加工设计方法。最后,本文根据Autodesk Inventor软件在某组块项目中的实际应用,完整阐述了一种海洋钢结构加工设计的新思路。     

谈管线试压技术在石油化工工艺设计中的应用

石油化工生产过程中,往往采用大量管线,特别是石油的加工中,管线常常装载多种易燃物、易爆物,并需要进行试压实验。因此,管线试压技术在石油化工工艺设计中十分重要,本文就围绕着管线试压技术谈谈个人的看法。     

基于Pro/E榨汁机上盖注塑模具的3D设计及数控加工

从分析榨汁机上盖塑件的结构特点入手,介绍塑件侧面倒钩和双筒成型处理方式及注塑模具结构设计要点和模具工作过程,并用数控编程模块Pro/NC对模具型腔进行加工刀路设计,模拟其加工过程.     

模块管线运输新型临时固定装置研究与介绍

模块管线永久支架是按照投产正常运行的工况条件设计的,满足正常生产条件下的管线应力要求,但是在模块运输过程中,无论是陆地运输中急刹车,还是海上运输过程中遇风浪较大时,管线受瞬间载荷影响较大,受力情况与正常工况下大大不同。因此根据模块运输过程中管线受力状况设计制作了模块管线临时固定装置,可以实现运输过程中对管线三维方向的限位要求,目前已经在国外某大型油田项目中成功运用。     

Time averaged temperature calculations in pulse electrochemical machining. Part I: theoretical basis

Simulation of the temperature distribution during the Pulse Electrochemical Machining (PECM) process provides information on system design and guidelines for practical use. The pulses that are applied to the PECM system have to be described on a time scale that can be orders of magnitude smaller than the time scale on which the thermal effects evolve. If the full detail of the applied pulses has to be taken into account, the time accurate calculation of the temperature distribution in PECM can become a computationally very expensive procedure. A new approach is introduced by time averaging the heat sources of the system. Performing this, the time steps used during the calculations are no longer dictated by the pulse characteristics. Using this approach, computationally very cheap, yet satisfactory results can be obtained. In this part of the work, the hybrid calculation and the Quasi Steady State ShortCut (QSSSC) are introduced. The hybrid calculation is a method, by which averaged and pulsed heat sources are combined in one calculation. The QSSSC is a method for quickly calculating the Quasi Steady State (QSS) in numerical calculations with time stepping. Analytical solutions of simplified cases are studied to provide useful insights into the more general case. It is shown that the averaging technique adopted in this work does not always deliver perfect results. However, using a technique of shifting the pulses in time, the results can become very satisfactory yet still extremely cheap. The more general case, which will be solved numerically, can be found in part II [Smets et al. J Appl Electrochem (Submitted)] of this work.     

Fast and efficient synthesis of high molecular weight poly(epsilon‐caprolactone) diols by microwave‐assisted polymer synthesis

Because of advantageous features such as shorter reaction times, greater yields, limited generation of by‐products and relatively easy and straightforward scale‐up, microwave‐assisted synthesis has become a very appealing tool in organic synthesis. Conversely, its implementation in the context of the synthesis of biomaterials for biopharmaceutical applications has been more limited. The present work reports on the fast and efficient microwave‐assisted synthesis of poly(ethylene glycol) (PEG)‐initiated poly(ε‐caprolactone) diols (PCL) by the ring‐opening polymerization (ROP) of ε‐caprolactone using stannous octanoate as catalyst. Since the PEG content in the synthesized copolymers was extremely low (0.2–1.9%), products were highly hydrophobic and displayed the intrinsic thermal properties of pure PCL. As opposed to the more time‐consuming conventional thermally‐driven synthesis that usually demands 2–3 h, the microwave technique resulted in intermediate to high molecular weight PEG‐PCL derivatives within 10–15 min. The influence of different parameters affecting the synthetic process, namely monomer‐to‐initiator ratio, reaction time, catalyst concentration and the presence, type, and concentration of solvent were thoroughly investigated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

商用车驾驶室涂装线智能控制系统的开发与应用

介绍了基于负载信号激励的能耗装置智能控制系统、网络化的信号交互功能操作系统模块和基于虚拟涂装工艺流程的实时监控系统的人机界面。实践表明,新开发的控制系统和涂装线运行稳定,对涂装线节能降耗具有实用和推广价值。     

Continuous Flow Methylene Blue Active Substances Method for the Determination of Anionic Surfactants in River Water and Biodegradation Test Samples

Anionic surfactants are commonly determined with the use of the methylene blue active substances (MBAS) standard method, which is time‐consuming and labor‐intensive. Therefore, new methods for determination of anionic surfactants are needed. In this study, the standard MBAS method for determination of anionic surfactants was modified and adjusted to work in a continuous flow system combined with spectrophotometric measurement. The developed method was found to be satisfactory in terms of sensitivity and precision, with a short time of analysis. The quantification limit for anionic surfactants was at 16 μg L^?1, with a relative standard deviation of 1.3 % for a model sample and 3.8 % for a river water sample. The results obtained for environmental samples were comparable to those obtained by using the standard MBAS method; however, the developed continuous flow method is faster, more sensitive and consumes smaller doses of chemical reagents.     

新一代的自适应模型预测控制器

提出了新一代的自适应模型预测控制器,自适应MPC控制器由MPC控制模块、在线辨识模块、性能监控模块3个模块组成,相互协调配和来实现自适应MPC控制。除了控制器功能设计以外,其余过程均可自动进行。对于新建MPC应用,首先进行多变量测试与辨识,在模型符合控制要求时,自动进入控制器投运。通过控制器性能监视发现模型不满足控制要求精度时,触发一次多变量模型测试与辨识过程,替换原有模型进行控制,保证控制器性能始终处于最佳状态。自适应MPC控制器在PTA装置上的应用表明了算法的有效性。     

Correlations between quinoline and 1-methyl-2-pyrrolidinone insolubles in petroleum pitches

Quinoline insoluble content (QI) still constitutes one of the most important physico-chemical parameters for evaluating pitches. However, quinoline is highly toxic, expensive, and the ASTM D2318 procedure is very time consuming. The solvent 1-methyl-2-pyrrolidinone (NMP) is less expensive, less toxic, and has recently become preferred as a pitch solvent by many researchers. Nonetheless, its use has not yet become standard for carbon researchers or the carbon industry because it has not been correlated with conventional QI results. The present article establishes correlations between quinoline insolubles (QI) and 1-methyl-2-pyrrolidinone insolubles (NMPI) for petroleum pitches using glass microfiber filters instead of the usual porous crucible.     

Modelling of pervaporation: Parameter estimation and model development

Pervaporation is proved to be a commercially viable membrane separation process by this time. However, to become a widely applied process in the industry it is of crucial importance to develop membrane properties, process and module design as well as proper modelling in professional software environment. In this work a pervaporation model improvement of the basic solution–diffusion model (Rautenbach et al., 1990) is recommended and tested on experimental data. The reason behind this improvement is that the transport coefficient cannot be considered as constant assumed in the basic model in a wide concentration range. The change of the transport coefficient is considered as an exponential function of the composition of permeating compound. This exponential dependency is assumed by the authors after investigating the shape of the flux curves measured in a wider feed concentration range. The accuracy of this improved model is experimentally tested with the pervaporation of isobutanol–water, n-butanol–water, and ethanol–water mixtures on commercial hydrophilic composite membranes. This model improvement gives accurate and reliable data for a wide range of feed concentration proving that the assumption of practically constant transport coefficient cannot be applied. Therefore the use of this improved model in professional flowsheeting software packages is more reliable and reasonable than the application of the basic model for the design and operation of pervaporation, or a more effective hybrid separation system including pervaporation.     

An integrated framework for on-line supervised optimization

In this paper, an integrated supervisory framework is envisaged for more robust on-line optimization and exception handling. This system takes advantage of the capabilities of real time evolution algorithm [Sequeira, S., Graells, M., Puigjaner, L. (2002). Real time evolution for Online Optimization of Continuous Processes. Industrial & Engineering Chemistry Research 41, 1815–1825] plus a fault diagnosis system (FDS) for managing abnormal situations. Both systems are part of a supervisory module which is responsible for handling plant incidences (faults and disturbances) by taking the appropriate corrective actions. Thus, a more satisfactory on-line performance is achieved, while reaction to incidence is enhanced by providing combined cause-effect information to plant managers. The implementation of the supervised real time evolution scheme has been performed using Matlab and the commercial simulation package HYSYS.Plant, taking advantage of their communication capabilities (COM technology). The developed fault diagnosis system comprises a detection module based on multivariate statistical techniques and an isolation module that uses an artificial neural network as a pattern classifier. The benefits of this framework are illustrated through a case study consisting in a debutanizer distillation column. The handling of various plant incidences, involving different sources and types of disturbances are considered. Finally, results of the supervised real time evolution (SRTE) are compared with those obtained using the standard real time optimization approach (RTO), showing superior performance in most of the cases.     

Generalized Pinch Analysis Scheme Using MATLAB

In pinch analysis, the calculations needed for determining pinch temperatures and minimum utility requirements are simple and can be done manually in case of a small number of streams. However, in real‐scale industrial problems, the calculation can become tedious and very much time‐consuming. A generalized low‐cost and user‐friendly scheme for pinch design using MATLAB is proposed. This scheme is tested for several problems for accuracy and robustness to determine hot pinch temperature, cold pinch temperature, minimum cooling load, and minimum heating load using the temperature interval method. The solutions developed by the proposed scheme are mirror images of solutions found by applying a rigorous procedure.     

Trajectory tracking of a batch polymerization reactor based on input–output-linearization of a neural process model

Input–output-linearization via state feedback offers the potential to serve as a practical and systematic design methodology for nonlinear control systems. Nevertheless, its widespread use is delayed due to the fact that developing an accurate plant model based on physical principles is often too costly and time consuming. Data-based modeling of dynamic systems using neural networks offers a cost-effective alternative. This work describes the methodology of input–output-linearization using neural process models and gives an extended simulative case study of its application to trajectory tracking of a batch polymerization reactor.