滑动叉无飞边锻造工艺研究

滑动叉传统上采用开式模锻工艺生产,飞边大,材料浪费严重而且尺寸精度差。为了降低锻件成本,针对滑动叉的形状特征,提出一种无飞边模锻的新工艺,使预制毛坯在封闭的模腔内成形,实现净成形或近净成形。应用Deform 3D模拟研究了滑动叉无飞边锻造工艺过程,模拟验证结果表明,新工艺显著地提高了材料利用率和成形质量,降低了锻造载荷。     

铝合金控制臂多向挤压制坯及模锻成形工艺

提出了采用多向挤压工艺为复杂枝权类控制臂锻件成形锻造预制坯。选取典型的复杂铝合金控制臂锻件,通过有限元模拟分析,研究了多向挤压成形过程中毛坯温度、材料流动速度、流线及挤压成形力和模锻成形过程中的温度分布及模具充填情况。模拟结果表明:当坯料成形温度为540℃、模具加热保温至200℃时,挤压后两枝权温度为520℃,枝权头部温度约为480℃,无须进行二次加热。模锻成形材料变形均匀,模具充填效果好,飞边较小,表明挤压制坯与锻造型腔较好匹配。最后,通过多向液压机对模拟进行了验证,结果表明,多向挤压制坯成形工艺可以获得高质量的控制臂锻件预制坯,该工艺具有可行性。     

十字轴小飞边精密成形工艺

针对十字轴热模锻成形过程中飞边大、成形力大的问题,根据十字轴形状尺寸及锻造成形工艺特点,提出十字轴小飞边精密成形工艺。采用Deform-3D对十字轴小飞边精密成形工艺过程进行数值模拟,对模拟成形的十字轴锻件及其金属速度场、等效应变、模具载荷-时间曲线进行分析。模拟结果显示,十字轴锻件成形完整,金属流动均匀,模具载荷减小。结合模拟结果,设计制造模具进行十字轴成形工艺试验。试验得到的十字轴锻件,填充饱满,无折叠、表面裂纹等缺陷,飞边明显减小,与模拟结果一致。结果表明:改变十字轴热模锻成形工艺,采用十字轴小飞边精密成形工艺,使锻件飞边减小,锻造过程成形载荷降低。     

滑动叉模锻成形技术北大核心CSCD

叉类锻件的工艺难点是劈叉,其材料利用率一般较低。通过分析某一型号短空心轴滑动叉的外形和金属分布规律,提出了弯曲成形U形叉、挤压成形空心杆的模锻思路,制定了5步模锻工艺方案。预锻成形时进行弯曲和挤压复合变形,毛坯在凸模作用下弯曲为U形,并挤压成形部分杆部;终锻成形时,利用预锻件的外形定位,挤压成形空心杆部,并对U形叉进行整形。模拟了预锻和终锻成形过程,验证了理论分析的正确性。根据制定的成形方案,设计制造了锻模,并模锻成形出合格的锻件。该方案避免了开式挤压劈叉工艺造成的材料流动不均匀的问题,同时成形了空心杆部、降低了金属消耗和机械加工量,而模锻成形产生的飞边和冲孔连皮可利用模具切除。相对于坯料水平分模开式模锻,该方案材料利用率提高约15%,对生产具有一定的指导意义。     

飞边槽结构形式对模锻成形的影响

开式模锻中飞边槽的形式对锻件成形过程的影响较大。本文通过大型体积成形有限元模拟软件DEFORM对采用不同形式飞边槽的锻件锻造过程进行了模拟，通过比较模拟结果得出不同形式飞边槽对模锻成形的影响，并就不同形式飞边槽在开式模锻中对模具型腔的填充性和模锻力的影响进行了详细分析。     

短轴滑动叉模锻工艺

针对在叉类件的模锻工艺中易出现开式模锻材料利用率低的问题,在研究传统水平分模开式模锻的材料流动特点基础上,根据锻件的外形结构提出了轴线与锻造方向一致的开式模锻新工艺,即弯曲、 挤压复合成形工艺.分析了材料的变形方式和流动规律,制定了5步开式模锻工艺,该工艺在成形时可以模锻出杆部的孔.对制定的模锻工艺进行数值模拟,证明了...     

CH1018转向节锤锻模具优化设计实例

针对CH1018转向节锻件,基于其形状、结构和锻造成形工艺,分析了其在模锻中的成形难点,并结合锻造工艺方案及主锻造设备吨位的计算,对预锻模型腔及其飞边槽进行了优化设计,飞边槽采用双仓结构,飞边桥间隙由4 mm优化至3 mm,桥宽由10 mm增加至12 mm,并应用到实际批量化生产制造中。优化设计后采用机械压力机并结合制坯模具,对制坯、预成形工步进行了简化,得到的锻件充填效果好、结构紧凑、材料利用率高、生产效率高,产品合格率由95. 6%提高至99. 2%。此设计实例为叉孔类复杂锻件的成形提供了一种在机械压力机上制坯与锤上模锻相结合的方法。     

带阻力坎结构销轨锻模的设计及数值模拟分析

热模锻压力机上采用两工位模锻工艺成形的销轨锻件,金属变形均匀、充填性好。对126型销轨热模锻压力机上模锻工艺进行理论设计,在预锻模的设计中采用了阻力坎形式的飞边结构,并对该飞边结构下的销轨成形质量、锻造载荷以及模具磨损情况进行了数值分析。通过数值模拟分析发现,在预锻模上采用阻力坎结构的飞边槽,能够大幅提高坯料金属充填型腔的能力,获得优质锻件,但容易导致成形载荷明显增大,需要进一步对阻力坎各部位进行尺寸优化,降低预锻模载荷。     

内燃机车滑动叉模锻工艺研究

分析成型滑动叉原工艺的不足，设计新的锻造工艺，将2个锻件叉口处对合，合体锻件变为形状简单、无叉口的长轴类形状，采用整体合锻方式模锻成形，使终锻由原1模1件变为1模2件，解决了原工艺生产中出现的锻造质量问题，可降低锻造成本，为同类锻件的工艺及工装设计提供一定的参考。     

可分式无飞边模锻的研发与应用

在介绍实现闭式无飞边模锻技术的基础上,阐述了闭式无飞边模锻工艺原理及特点,研发不同合模机构组成的可分凹模模锻装置,与相应的通用模锻设备构成专用的无飞边闭式模锻装备系统,实现多种中小型复杂锻件的精密模锻生产。应用效果表明,可分式无飞边模锻能够实现复杂锻件的精密成形,产品精度高、力学性能好,材料利用率高。     

锂鱼钳无毛边模锻工艺及模具设计

叙述了锂鱼钳塑性变形的工艺分析、设计锻件图及计算毛坯截面图和直径图。介绍了锂鱼钳无毛边模具结构及生产工艺流程。阐明了用无毛边模锻工艺代替传统旧工艺的优点。文末列举了新旧工艺的技术经济比较。     

Finite element investigation of curvature in the roll platen forming process

A novel roll-platen forming process described in this paper has been proposed for the production of elongated components to net shape or near net shape. Although significant progress in net shape forging has been achieved in circular and axisymmetric components through flashless forging with completely closed die cavity techniques, similar progress has not been reported for elongated components. The feasibility of this process has been demonstrated through physical modelling experiments with Plasticine. This process essentially consists of a single roll and a flat platen. The platen can move with a speed equal to or higher than that of the peripheral speed of the roll. When it moves with a higher speed, the deformed workpiece becomes curved. With this characteristic, the roll-platen forming process seems promising for the manufacture of curved elongate components to near net shape. This paper presents an investigation of how the curvature is influenced by the speed ratio. The detailed results of curvature, as well as the distribution of generalised strain, strain rate, and mass flow will be given. The finite-element predicted curvature is shown to agree with previous experimental observations.     

摩擦压力机闭式模锻工艺的应用

叙述了闭式模锻工艺的实质、特点、方式及模具型式，列举了典型的闭式模具结构图。阐述了用闭式模锻工艺代替开式模锻的优点。文末提出了模具设计的基本要求。     

Design of forging dies for forming flashless ring gear blanks using finite element methods

In the forging industry today, advanced mathematical techniques such as finite element methods (FEM) are beginning to revolutionize the conventional trial-and-error methods for die design and forging process development. Cost reduction programs are being implemented to enable the forging industry to remain competitive in today’s market. Material reduction or weight savings in the quantity of metal required to make the forged part is proving to be a significant factor contributing to cost reduction. Production of ring gear blanks without producing flash reduces the input weight of metal needed to make the gear blank, thus providing cost savings on the forged part. The following paper discusses different approaches currently used to make flashless ring gear blanks. The paper also describes the application of the rigid-viscoplastic finite element code “ALPID,” developed by Battelle Labs, Ohio, in developing a hot forging process to produce flashless ring gear blanks. The metal flow simulations, using ALPID, provide a tool to design and develop die cavities for defect-free closed die forging processes for making flashless ring gear blanks. The forming loads from these simulations are then applied to the forging die and the stresses on the die analyzed using another FEM based stress analysis package (“IDEAS,” developed by SDRC, Ohio) to verify the die design for strength in the given application. Thus, finite element methods were applied in different aspects of forging die design.     

羊角锤闭式精密模锻工艺及模具设计

叙述了羊角锤新旧模锻工艺过程,介绍了活动模具的动作原理及模具结构,阐述了用闭式精密模锻工艺代替普通模锻的优点,提出了模具设计的基本要求,指出了目前使用活动模具闭式精密模锻中所存在的问题     

齿轮坯闭式模锻模具参数化设计系统的研制

针对齿轮坯闭式模锻模具设计，详细研究了其参数化设计过程及其二次开发的方法和技术，成功开发了齿轮坯闭式模锻模具参数化设计系统，实现了齿轮坯闭式模锻模具参数化绘图。     

Past developments and future trends in the rotary or orbital forging process

Rotary forging is a relatively new manufacturing process with potential for cost-effective applications, especially in cold forging of intricate parts to net shape. In this paper orbital forging and axial die rolling processes are included as subsets of rotary forging while radial forging, also known as rotary forging, has been excluded; these decisions are primarily based on die kinematics. Because of its recent origins, the rotary forging process is first described. Then, a historical perspective is provided to trace its recent origins. The machines are classified based on die kinematics. Die kinematics influence the stick-slip or position discrepancy behavior of the different machine types and have deep implications on the die filling and accuracy capabilities of these machines. Rotary forging machines currently in operation in the U.S. and their applications are presented in greater detail. The discussion on future applications and potential research issues is primary based on the author’s own perception of future trends in this emerging field. The author is with.     

Flashless precision forging of a two-cylinder-crankshaft

Flashless precision forging is a special process of drop forging performed in closed dies. This process is distinguished by high quality and the ability to achieve a near net-shape part. Latest research results have shown that it is possible to forge a two-cylinder crankshaft without flash. This was realized using a multi-directional forging tool and a flashless precision forging operation. A new method for a three dimensional shrinking compensation facilitates the construction process.     

活扳手扳口闭式精密模锻工艺

介绍了活扳手扳口新的模锻工艺流程，阐述了镦粗一成形制坏工艺、闭式精密模锻工艺及其模具结构设计，比较了新旧工艺的技术经济效益。结果表明，闭式精锻工艺的新方法是十分有效的。