圆柱直齿轮冷精锻模具工装设计

为将圆柱直齿轮冷精锻技术应用于实际生产,提出了齿腔分流工艺,并为该工艺设计了专用模具工装。通过有限元模拟校核了模具关键零件的强度,并采用20CrMnTi坯料进行实验研究,验证该工艺方案及模具结构的合理性。结果表明,齿腔分流工艺能很好地成形出20CrMnTi齿轮锻件;模具结构合理,满足生产强度要求,出模容易。     

线切割同时加工无边落料凸凹模

我厂是一个多年生产机床电器的厂家,多数冲裁模具离不开线切割机床加工。为节约用料,一些产品零部件的工装设计采用了无边落料方式,对一些无边落料冲裁模具利用线切割机床同时加工出凸凹模,经实际使用切实可行(此种方法本刊曾介绍过,其穿丝孔处利用切槽镶件解决,而无边落料模的穿丝孔不必切槽镶件)。     

冠形齿片精冲级进模设计

分析了冠形齿片成形工艺,介绍了冠形齿片排样方案和级进模结构,级进模各工位功能件采用镶拼结构,便于制造、修正、更换,以降低模具的制造成本。生产实践证明:级进模结构合理,能保证产品质量,生产效率高。     

弹性接触片多工序复合模

对传统的工艺进行了改进，采用了多工序复合模一次成形弹性接触片。介绍了复合模的结构特点及工作过程，成形凸凹模采用了镶拼结构，成形凹模采用活动结构，并采用了弹顶推料装置。凹模、凸凹模均为圆柱形，制造非常方便。凸凹模镶块和凸模成形面为螺旋面，制造较为困难。经生产验证，该模具结构合理、生产效率高、经济效益显着。     

一种挤压半空心铝型材的遮盖式一模双孔分流模的结构

提出了一种针对半空心铝型材采用遮盖式一模双孔的挤压模结构。通过实际例子,详细介绍了这种模具结构有关参数的选择。主要包括挤压机能力的选择,模孔布置、分流孔设计、下模焊合室结构和工作带的选择。介绍了模具强度的校核方法。将传统的平面模、单孔分流模与这种新的遮盖式双孔模的实际挤压结果进行了对比。这种新的模具结构简单、容易加工。实践表明,采用这种新的一模双孔挤压模结构可显著提高模具的寿命、提高铝型材生产效率和降低成本,所得型材尺寸精度高、表面光亮,是一种值得推广的的模具结构。     

滚筒洗衣机外壳成形工艺与模具设计

介绍了洗衣机外壳加工工艺,设计出冲孔、翻边一次成形模结构,包括镶拼式结构,凸、凹模共用,减少了零件成形加工工序,缩短了模具生产周期,模具已投入生产,零件质量稳定,效果好。     

含镶针接插件注射模设计

根据含镶针接插件的结构特点,设计了1模2腔的双下模式注射模,采用上模压紧装置保证骨架镶件的位置精度;通过手动方式,在模具合模前,将L形镶针放置在抽芯滑块型孔的准确位置,使滑块预先进入合模位置,保证塑件成型质量,最后借助嵌入式组合滑块实现塑件腰形凹槽侧向抽芯。经实际生产验证,模具动作可靠,结构合理,塑件脱模顺利,塑件尺寸合格,表面质量良好。     

汽车后悬弹簧支座加强板模具设计

分析了汽车后悬弹簧支座加强板的冲压工艺,制定了三工序及1模2件对称成形零件的冲压方案,并介绍了模具结构特点及模具关键零部件的设计,模具中凸、凹模均采用镶件结构,便于制造和维修。经实际生产证明,模具结构紧凑合理、操作方便,生产的零件质量稳定,满足精度要求和大批量生产的要求。     

半空心铝型材挤压模的设计

半空心铝型材是很常见的铝材,这些型材的挤压模具的主要问题是模具强度不够。分别介绍了为保证半空心型材挤压模具的强度而设计的几种模具结构,它们是一体式整体平面模、遮盖式分流模、遮盖式导流模、碰穿式分流模与整体式分流模。在生产实践中,可以根据半空心型材的结构特点与质量要求来选择与之相适应的模具结构。     

生产汽车换热器平行流铝扁管的硬质合金镶嵌挤压模

分析了汽车换热器平行流铝扁管的结构和传统挤压模具结构的特点。提出采用硬质合金镶嵌挤压模的结构。介绍了上模模芯采用硬质合金镶嵌的原理,利用斜面结构具有自动补偿和自锁的特点,并对传统的模具结构进行改进,增设前置分流保护板,同时在上模开设工艺槽,其结果是降低了硬质合金镶件的受力,提高了硬质合金镶件的稳定性以及上下模配合间隙的准确性。还介绍了下模的硬质合金镶嵌方法,利用硬质合金与钢材线膨胀系数的差异,采用销子定位的方式,可以使销子与硬质合金镶件的配合由常温下的间隙配合变成高温工作下的过盈配合,结果是硬质合金的镶嵌更加牢固可靠。实践表明效果良好,挤压模具的寿命大大提高。     

Investigation on Effects of Die Orifice Layout on Three-Hole Porthole Extrusion of Aluminum Alloy 6063 Tubes

Currently, with the increasing demand of high production output, much attention is paid to the research and development of multi-hole extrusion die. However, owing to the complexity of multi-hole porthole extrusion technology, it has not been applied widely in practice for the production of aluminum profiles, especially for porthole die with an odd number of die orifices. The purpose of this study is to design a three-hole porthole die for producing an aluminum tube and to optimize the location of die orifices based on computer-aided design and engineering. First, three-hole extrusion dies for different locations of die orifices are designed. Then, extrusion processes with different multi-hole porthole dies are simulated by means of HyperXtrude. Through numerical simulation, metal flow, temperature distribution, welding pressure, extrusion load, and die stress, etc. could be obtained, and the effects of the location of die orifices on extrusion process are investigated. With the increasing distance between die orifice and extrusion center (described as eccentricity ratio), metal flow becomes nonhomogeneous, and twisting or bending deformation of profile occurs, but the welding pressure rises, which improves the welding quality of profiles. However, the required extrusion force, billet and die temperature, die displacement, and stress induce no significant changes. In comparison with the extrusion force during single-hole porthole extrusion, there is 18.5% decrease of extrusion force during three-hole porthole extrusion. Finally, design rules for this kind of multi-hole extrusion dies are summarized.     

平面分流组合模三维实体造型与有限元分析

以有限元软件ANSYS为工作平台,建立了平面分流组合模的三维实体模型,在确定边界条件和工作载荷的基础上,对模具在挤压过程中的温度场和应力场进行了有限元计算。通过对计算结果进行分析发现,在模桥与模芯相接处有较大的应力集中,与出现裂纹的位置相吻合,说明应力集中是模具桥裂的主要原因之一,这一结果与生产实际情况相吻合。     

A new approach to study material bonding in extrusion porthole dies

Porthole die extrusion processes are widely spread even for most recent industrial applications. In turn knowledge base is often linked to make best expertise rather than to scientific fundaments. In the last years several FE models were developed but actual material bonding was not taken into account. In the paper a new approach is presented determining the critical value of the bonding criterion from flat rolling experiments and modelling the actual welding occurring in extrusion of complex profiles.The criterion was tested considering an industrial porthole die extrusion process and experimental parts were analysed to validate the proposed approach.     

铝型材分流模设计中关键参数的确定

介绍了分流组合模设计中模具结构的选择,分流孔的布置,分流桥的结构,以及模芯、焊合室、工作带等重要参数的确定方法。     

半空心铝型材保护导流式分流模结构

介绍了半空心铝型材挤压模的研究现状,分析了针对半空心铝型材的5种模具结构,包括整体式平模、镶嵌式分流模、遮盖式分流模、吊挂式分流模和切割式分流模。提出了一种新的半空心铝型材挤压的保护导流式分流模具结构,结合具体实例,介绍了这种保护导流式挤压模结构,详细分析了这种结构的组成和参数选择,主要包括分流孔的设计、挤压机能力的选择、分流桥的结构、应力间隙和工作带的选择,并给出了模具强度校核方法。根据挤压结果,与传统平面模、切割式分流模进行了对比。结果表明,这种新型模具结构简单、便于加工,可显著提高模具强度和寿命。     

分流组合模挤压的有限元模拟与模具设计评价

为探讨分流组合模挤压成形规律,选择分流孔内斜度、外斜度、焊合室高度和工作带长度为变量设计了9副模具,提出了模具设计的无量纲单指标评价因子和综合评价函数,用DEFORM_3D软件实现了分流组合模挤压铝管材的有限元模拟,获得了挤压材料焊合面上的静水压应力场、等效应变场和模具峰值应力,进而对模具设计评价指标进行了极差分析,得到了最优模具设计,模拟分析结果与试验数据吻合良好。研究表明:分流组合模焊合室高度H与工作带长度L的比值对综合评价函数影响很大,应作为设计变量。     

挤压速度对铝型材分流模寿命影响的模拟分析

挤压速度是影响铝型材分流模寿命的主要因素之一。不同挤压速度下,模具所受温度和压力不同,对模具寿命产生直接影响。以矩形管铝型材挤压为例,利用Deform有限元分析软件对挤压过程进行数值模拟,得到不同挤压速度下分流模温度和压力变化情况。结果表明:随挤压速度的增大,分流模各工作部位温度逐渐升高,而所承受压力则先降低后升高。探讨了温度和压力的改变对模具寿命的影响机制,指出挤压速度对模具寿命的影响表现为加速模具各工作部分的塑性变形、磨损和应力集中部位失效,以及加剧挤压模的冷热疲劳现象。     

复杂断面空心型材的双级分流模挤压过程模拟分析

对于非对称断面、大壁厚且空心的复杂断面空心铝型材,采用常规分流模挤压时很难平衡金属流速,型材挤出后经常产生弯曲或扭拧现象。为此,提出了在常规分流模前增加一级分流模,使传统的分流-焊合-成形的3个阶段变为预分流-分流-焊合-成形的4个阶段,进而达到平衡金属流速目的。研究结果表明:双级分流模比常规分流模挤压时金属流动均匀性得到了改善;各孔金属流速平均值为6.41 mm·s-1,方差为0.2511且降低了65%;挤压温度场分布均匀,温差在7~12℃之间范围内,抵消了温差不均匀的影响;焊合室内静水压力平均值约为290 MPa,模芯周围静水压力分布均匀,模芯不易发生移动。     

铝型材挤压分流模工况分析及其受力变形研究现状

通过对铝型材挤压分流模工作状况的分析,说明其在复杂的工况下会发生一定的变形,尤其是模芯部分,这不仅降低了产品的尺寸精度和表面质量,也降低了其寿命.介绍了国内外应用有限元方法对铝型材挤压过程研究的状况,提出了对铝型材挤压过程中分流模的变形进行有限元数值模拟研究的思路,为模具的科学、合理设计提供依据,以达到提高产品尺寸精度,提高模具寿命的目的.     

AM30 porthole die extrusions—A comparison with circular seamless extruded tubes

One of the prospective applications of wrought AM30 magnesium alloy is in the form of hollow circular extrusions. They can either be fabricated by employing a conventional conical die and mandrel that produce seamless extrudates, or by using a porthole die employing a welding chamber technique. The latter has become popular due to several advantages and has been adopted commercially for aluminium and magnesium alloy extrusions. In the present investigation, cast billets of AM30 magnesium alloy were extruded under similar conditions, using two different dies, i.e., a conventional conical die and a commercially used porthole die. The extruded circular tubes produced by the two methods were characterized for their microstructure as well as physical and mechanical properties. The tubes fabricated using porthole die showed significant refinement in microstructure with improved mechanical properties, outside the seam-joint portion, compared to the tubes fabricated using conical die. The extrusion loads using porthole die, were, however, higher compared to the conventional method. Processing issues, structure and properties of magnesium extrusions, produced by the two methods, are discussed in details in this paper.