快启式全自紧高压密封装置的设计

本文主要以最低制造成本为设计目标,根据试验和理论分析结果,给出了新型高压密封装置的强度设计方法,并提出了一种结构紧凑,制造简便,装拆方便,顶盖用途不受限制的全自紧式密封装置,通过设计实例的演算,得出用优化设计可降低制造成本的结论。     

现代先进设计技术综述

先进设计技术是先进制造技术的一个重要组成部分,它是制造技术中的首要环节,据有关资料介绍,产品设计成本约占产品总成本的10%,但却决定了产品制造成本的70%~80%,所以设计技术在制造技术中的作用和地位是举足轻重的。本文对现代先进设计技术作了一个综述,并介绍了先进设计技术的发展趋势及未来的绿色设计、综合智能优化设计。     

管壳式换热器设计分析

管壳式换热器设计分析,目的一是提高传热效率的分析,二是降低设备加工制造成本的设计分析。优化设计是使能量最大限度被利用,最终获得最大的经济效益。本文从两个方面简要介绍了管壳式换热器的设计。     

低成本碳纤维的研究进展与应用

碳纤维具有优异的力学性能，因此碳纤维及其复合材料在越来越多的行业中得到应用。然而，受限于碳纤维较高的制造成本，限制了碳纤维在风电、汽车、建筑增强材料等领域的规模化应用。近年来，世界多国对低成本碳纤维的研究付出了很多努力。碳纤维原丝制造成本是影响碳纤维制造成本的主要因素，这是目前低成本碳纤维的主要研究方向。综述了采用降低碳纤维原丝制造成本，进而降低碳纤维制造成本相关技术的研究进展，并对低成本碳纤维的应用领域现状进行了总结。     

制造型企业如何降低成本系列（二）——从降低材料成本来提升企业核心竞争力

在制造型企业，大部分产品的成本中，材料成本占了60％以上，机械行业、五金制造等，材料成本占了绝大部分，这让我们意识到降低材料成本的重要性。但如何降低材料成本呢？笔者将从材料在工厂的不同阶段来加以说明：     

并联低温多效海水淡化系统优化与分析

建立了并联流程下的低温多效蒸发海水淡化系统优化数学模型。该模型以整个系统的单位产量淡水成本最小为优化目标,以加热蒸汽温度及各效二次蒸汽温度为决策变量,并应用MATLAB及其优化工具箱对其进行了求解,同时与非优化设计情况进行了比较。结果表明:当淡水产量不变,随着效数的增加,淡水成本先减小后增大,最优效数为7效,优化淡水成本为5.51元/t;与非优化设计相比,在达到6效之前,优化设计的加热蒸汽量减小,蒸发器传热面积增大,优化设计的淡水成本小于非优化设计的淡水成本。在6效之后,二者相差不大。     

基于LCA-LCC的沥青路面结构优化设计流程

为了降低沥青路面结构全生命周期对环境的影响并减少应用成本,基于LCA-LCC理论,在常规沥青路面结构设计流程的基础上,提出了优化设计流程：确定目标路段和清单数据,提出和确定重等交通优化设计方案,提出和确定中等交通优化设计方案,以及核验并输出优化设计成果。该优化设计流程对于今后的公路沥青路面结构设计有效降低环境影响、减少应用成本具有参考意义。     

国产石墨电极平均制造成本最新指数发布

近日，中国炭素行业协会发布了国产石墨电极平均制造成本指数（见表1）。据该协会负责人陈国强介绍。这次发布的该指数，是在广泛收集各主要石墨电极生产厂家的原材料数据基础上制定的，旨在及时反映石墨电极原材料价格变化对石墨电极制造成本的影响。这一指数是制造成本指数，不是全成本指数，更不是价格指数。因为财务费用、管理费用、销售费用以及折旧等构成全成本和价格的其它重要部分并没有纳入指数的计算中。     

2006年聚酯加工丝制造成本比较

国际纤维制品制造业者联合会（ITMF）发表“纺织成本的国际比较”2006年调查。在聚酯加工丝制造成本的调查对象中，中国制造成本最低，1．74美元／kg，印度其次，1．77美元/kg。两国都是因为劳务费低廉，成本低。     

多晶硅生产中大型塔再沸器的结构设计改进

介绍了大型塔再沸器的结构特点。从管板、换热管与管板连接接头、管箱和支座方面对塔再沸器进行了结构设计改进。改进后的塔再沸器重量减小16.3%,制造成本显著降低。消除了主要的泄漏隐患,使设备运行更加安全可靠。为大型换热器的优化设计提供了可供借鉴的经验。     

Experimental investigation and cost assessment of the salt production by solar assisted evaporation of saturated brine

The technical feasibility and economy of solar heat collection-forced evaporation process are the keys to its practicality,especially its application in strong brine treatment.The operation cost of applying solar collection in salt manufacturing through depth evaporation of brine has been studied.For Na~+,K~+,Mg~(2+)//Cl~-,SO_4~(2-)-H_2O salt–water system,most of the Na Cl and all of the Carnallite were separated.The operation cost reached the optimum when the heat collection and evaporation were controlled at 75 and 55°C,respectively.When the solar radiation amount was 19557 kJ·m~(-2)·d~(-1),the solar collector area for producing Carnallite was about 34.27 m~2·(t salt)~(-1),and the operation cost was 13 USD?(t salt)~(-1).The energy consumption of salt manufacturing is at least 25%higher than that of natural evaporation.Regarding the economy,the solar assisted salt manufacturing process is recommended to be performed at a production scale of more than 20 tons per day.     

Pilot run,plant design and cost analysis for reductive ozonolysis of methyl soyate

Preparation of methyl azelaaldehydate dimethyl acetal (MAzDA) from methyl soyate was investigated on a pilot scale via the sequence ozonization, hydrogenation, acetalization and fractional distillation. A water-methyl soyate emulsion for the ozonization step was preferred to methanolic solution or neat methyl soyate for reasons of cost and safety. Ozonization of the water-methyl soyate emulsion (1.63:1 ratio) in a six-plate sieve tower produced 1271 lb aqueous peroxidic emulsion during 12 days of continuous operation. Because a continuous hydrogenation facility was not available, reduction was done in 200 lb batches. Since batch hydrogenation of the peroxidic emulsion in this quantity was difficult to control and optimum conditions were difficult to maintain, maximum yield of the product was only 56%. The average yield for seven batches was 48.3%. However laboratory hydrogenation under optimum conditions of periodic samples taken from the sieve tower discharge indicated an overall yield of 74.5% (average of eight monitor samples). A plant designed to produce 10 million lb annually should be capable of producing MAzDA at a total manufacturing cost of 39 cents/lb or a net manufacturing cost of 27 cents/lb with byproduct credit conservatively estimated. Methyl soyate ozonolysis products are not sensitive to detonation, and their exothermic decomposition is greatly moderated by the presence of water. Presented in part at the AOCS Meeting, New Orleans, May 1967; see Abstr. 117, JAOCS 44:139A (1967). ARS, USDA.     

双膜分离技术在利福霉素O提取中的应用

根据利福霉素O工艺过程中利福霉素B及利福霉素O的理化性质,两次利用无机陶瓷膜在利福霉素O生产中使用,确定了最佳工艺参数,优化了传统工艺,提高了产品收率及质量,同时新工艺大大地降低了溶媒消耗,节约生产成本。     

Numerical Optimization of the Annual Cost of a Clothes Dryer

Optimization of the energy cost of clothes dryers saves on energy use without requiring additional installations. To optimize the cost of clothes dryers, a correlation has been developed for the evaporative mass flux produced in the drum. The correlation was used to determine the drying time and cost. An objective function for the drying cost was defined in terms of the total annual dryer costs for energy usage, material, and manufacturing. The objective function (Annual cost) was optimized for two cases relative to 8-10 of the dryer parameters subject to various operating constraints using the direct search and the variable metric methods. The optimization results indicate that there are optimum settings for the fan speed and the drum speed depending on the weight of the drying load and heater power. The results showed that the optimum lies at the highest drying load and the lowest (37.45% in Annual cost could be saved) or the highest value of heater power (19.7% in Annual cost and 52.6% in drying time could be saved), whichever satisfies the drying time constraint. The applications of the optimization results are discussed.     

面向工艺指标的生产成本控制研究与运用

揭示了流程性制造业中工艺指标与生产成本之间的关系,通过对与生产成本有关的工艺指标的样本进行分析,采用多元线性回归对其进行曲线拟合,并利用极值原理找出最优控制区域,建立控制系统,运用于生产实践,取得了相当的效益,从而阐明了对面向工艺指标的生产成本控制研究是ERP成本系统研究中的一种新思路。     

A comparative study of vacuum‐assisted resin transfer molding (VARTM) for sandwich panels

Vacuum‐assisted resin transfer molding (VARTM) of sandwich panels can be facilitated by using high permeability layers (HPL) over the skins or adding channels in the surfaces of the core (CIC). The present paper investigates the advantages and disadvantages of both methods in terms of manufacturing cost and time through simulations and experimental observations. A cost model is developed, and the resin infusion time for each method was minimized through simulations. The design parameters are the number of high‐permeability layers and the number and size of channels. A penalty function with equal weight on cost and time is used to find the optimum values of the design parameters. Under the conditions studied, the optimal HPL method is found to be better than the optimal CIC method. While the conclusion is limited to the present study, the proposed approach can be used to optimize manufacturing processes for larger sandwich panels under different conditions.     

滴灌用全水溶MAP生产工艺综述

介绍目前我国滴灌用全水溶M AP的几种生产工艺及其优缺点;贵州宏福实业开发有限公司滴灌用M AP的技术指标及针对湿法磷酸生产滴灌用M AP的产品晶形过差所作出的结晶系统的优化设计。湿法磷酸生产M AP改进后的工艺生产的产品外观结晶粗大、整齐,生产成本低,缺点是能耗高,操作要求高,工艺过程复杂。     

Iterative approach to the study of optimal production policies for a multipurpose plant

A study of optimum operating conditions for operation of a multi-purpose nitrating plant is carried out by means of a decomposition technique. The plant is multipurpose inasmuch as three products—nitrobenzene, monotrichlorobenzene, nitrotoluene—can be produced with the same configuration of equipment. The decomposition procedure is applied to the analysis of the optimum structure of the plant and the economic environment, which identifies two sub-systems, namely the plant and inventory model. The technique facilitates the solution of the system, while preserving the dimensionality.

An economic global index of performance is taken as the present value, which can be optimised in terms of production rates, running times and number of runs for each individual process. For a particular set of market conditions a global optimum is defined and its sensitivity to some of the costs is assessed. It is found that, although the value of the index is sensitive to the level of unit manufacturing cost and unit selling price, the location of the optimum, and consequently the optimum operating strategy, remains unchanged for changes up to 5% in unit cost and price.     

纤维缠绕成型的CAD/CAM技术研究

纤维缠绕成型是制造高强度复合材料制品的一种重要的成型工艺方法，在国防和航天工业中占有重要地位，将CAD／CAM技术应用与缠绕中可以大大提高生产效率和产品质量、降低设计成本、缩短设计周期。简要概述了纤维缠绕成型CAD／CAM系统的总体方案、关键技术、优化设计，并介绍了国内外的研究进展。     

复合材料工型肋的RTM工艺模拟与优化

采用PAM-RTM模拟软件,对变截面工型肋结构零件进行RTM工艺注射方案设计。过程中,分别进行了6种注射方案的结果模拟,从注射方式、注射参数及注射口选择等方面进行方案设计,对注射过程中的压力分布、树脂浸润效果及注射时间进行比较,根据比较结果进行综合评定,最终得出了最优注射方案,并将结果用以指导工装设计,成型了验证零件。结果表明:采用计算模拟技术,可替代人工试验,进行工艺及工装方案设计与制造;工型肋的摆放位置对树脂的浸润趋势和注射时间影响较小,但注射口和注射方式选择对工型肋零件的影响很大,线注射方式及端部注射的浸润效果和效率要好于点注射及梢部注射。