WO2011015005A1

WO2011015005A1 - Method for casting planet carrier made of ductile cast-iron

Info

Publication number: WO2011015005A1
Application number: PCT/CN2009/075280
Authority: WO
Inventors: 杨金德; 郁晓兵; 孔建会
Original assignee: Yang Jinde; Yu Xiaobing; Kong Jianhui
Priority date: 2009-08-07
Filing date: 2009-12-03
Publication date: 2011-02-10
Also published as: CN101628323A

Abstract

A method for casting the planet carrier made of ductile cast-iron includes the processes of molding, smelting, spheroidizing, incubating, pouring and relief annealing. A step gate is used in the pouring process. Iron chills are arranged in the parts of the thick walls. Sn element is added in the smelting process. The spheroidizing process, the incubating process and the pouring process are optimized. The casting method improves efficiency and the planet carrier made by the casting method meets the requirement of the performance.

Description

说明书 Instruction manual

Title of Invention: —种球墨铸铁行星架的铸造方法技术领域 Title of Invention: A method for casting a ductile iron carrier

技术领域 Technical field

[1] 本发明属于球墨铸铁生产工艺领域，特别涉及一种齿轮箱用球墨铸铁行星架的铸造工艺。 [1] The invention belongs to the field of production process of ductile iron, and in particular relates to a casting process of a ductile iron carrier for a gearbox.

背景技术 Background technique

[2] 现有技术：目前，在球墨铸铁行星架的生产过程中，为了提高其生产进程，行业上一般都是釆用铸态生产的方法，但是，现有技术铸态生产的方式很难使球墨铸铁行星架达到力学性能方面的要求。 [2] Prior art: At present, in the production process of ductile iron planet carrier, in order to improve the production process, the industry generally uses the as-cast production method, but the prior art as-cast production method is difficult. The ductile iron planet carrier is required to meet the mechanical properties.

[3] 2兆瓦以上风电主传动齿轮箱关键部件-行星架的材质要求为 QT700 - 2，是齿轮箱内最为关键的部件，要求耐磨、强度高，但此铸件断面较厚大，均超过 100 mm,而其本体要求硬度为 HB225— 305，且硬度均匀性要求为 ±10HB。按传统工艺，一般是通过热处理后获得，此工艺相对来说，工艺成本高、效率低下、能耗较大。 [3] The key component of the main transmission gearbox of wind turbines above 2 MW--the material requirement of the planet carrier is QT700-2, which is the most critical component in the gearbox. It requires wear resistance and high strength, but the section of the casting is thicker and thicker. More than 100 mm, and its body hardness is HB225-305, and the hardness uniformity requirement is ±10HB. According to the traditional process, it is generally obtained by heat treatment. This process is relatively high in process cost, low in efficiency, and high in energy consumption.

对发明的公开 Disclosure of invention

技术问题 technical problem

[4] 本发明要解决的技术问题是：提供一种操作简单、能耗小、成本低、生产周期短，且制得的铸件组织均匀、性能好的齿轮箱用球墨铸铁行星架的铸造工艺。技术解决方案 [4] The technical problem to be solved by the present invention is to provide a casting process of a ductile iron carrier for a gearbox with simple operation, low energy consumption, low cost, short production cycle, and uniform casting structure and good performance. . Technical solution

[5] 一种球墨铸铁行星架的铸造工艺，包括造型工序、熔炼铁液工序、球化工序、孕育工序、浇注工序、正火工序和去应力退火工序，所述浇注工序中，在行星架的底盘和立柱的顶部设有 4-10根阶梯式内浇道，同吋进行浇注。所述造型工序中，在行星架的底盘和立柱的结合部位以及及底盘上凸台的两端部位摆放冷铁。所述熔炼铁液工序中，铁液中加入 Sn元素，所述 Sn元素的加入质量为铁液总质量的 0.015〜0.02%。所述球化工序中，釆用凹坑式的处理包形式，凹坑式的处理包形式是指球化处理包底部分为高低不平的两部分，剖切面呈阶梯形状，其中凹坑的面积占包底的 2/5〜1/2，凹深按容纳处理满包铁水所需的球化剂量而定。球化剂的加入质量为铁水质量的 1.2〜1.4%，并用硅铁粉覆盖在所述球化剂表面。所述孕育工序中，孕育次数为三次，分别是在球化反应包坑内覆盖在球化剂上面一次孕育、出水过程中出水四分之三吋的倒包二次孕育和浇注过程中的随流孕育。一次孕育加入量控制为 0.5%〜0.7%；倒包二次孕育是指为了延长孕育处理的有效作用吋间，在铁水转入小包吋，进行孕育处理，由于经球化处理和第一次孕育处理后铁水的温度已较低，因此此倒包二次孕育的剂量不宜过大，孕育剂粒度也要小于 5毫米，且最好烘至红热状态加入，还要充分搅拌，孕育剂加入量控制为 0.25%〜0.35%；随流孕育是指在浇注过程中，装有孕育剂的漏斗出口对准浇注的铁水流把孕育剂撒在铁水流上，在整个浇注过程中均匀的加入，由于浇注温度较低为防止铸件产生硅偏析要避免孕育剂粒度过大和加入量过多，加入量控制为 0.1%〜0.15%，漏斗出口尺寸控制为 φΐθ毫米。所述的浇注工序中，浇注温度控制在 1350°C〜1360°C，浇注工序完成后，检测铸型内铸件温度，控制在 850〜880°C进行幵箱，空冷至 520〜540°C，再放入盛有干砂的箱内并使用型砂进行覆盖，然后冷却至室温幵箱。 [5] a casting process of a ductile iron carrier, comprising a molding process, a smelting iron process, a spheroidizing process, a nurturing process, a casting process, a normalizing process, and a stress relief annealing process, wherein the casting process is in a carrier The top of the chassis and the column has 4-10 stepped gates, which are poured at the same time. In the molding process, cold iron is placed on the joint portion of the chassis and the column of the carrier and the both ends of the boss on the chassis. In the smelting iron liquid process, a Sn element is added to the molten iron, and the added mass of the Sn element is a total iron liquid. The quality is 0.015~0.02%. In the spheroidizing process, the pit type is in the form of a processing package, and the pit type processing package form refers to two parts of the bottom of the spheroidizing processing package which are divided into high and low, and the cutting surface has a stepped shape, wherein the area of the pit It occupies 2/5~1/2 of the bottom of the package, and the concave depth depends on the spheroidizing dose required to process the full package of molten iron. The spheroidizing agent is added in an amount of 1.2 to 1.4% by mass of the molten iron, and is covered with the ferrosilicon powder on the surface of the spheroidizing agent. In the gestation process, the number of gestation times is three times, which are respectively covered in the spheroidization reaction pit, which is covered by the spheroidizing agent, and the effluent in the effluent process is immersed in the second gestation and the flow in the pouring process. Grow. The amount of inoculation is controlled to be 0.5%~0.7%; the second inoculation refers to the effective effect of prolonging the inoculation process, and the fertilization is transferred to the small bag, and the inoculation is carried out, due to the spheroidization and the first breeding. After treatment, the temperature of the molten iron is already low, so the dose of the second inoculation should not be too large, and the inoculant should have a particle size of less than 5 mm, and it is better to add it to the red hot state, and to fully stir, the inoculant is added. The control is 0.25%~0.35%; the flow inoculation means that during the pouring process, the funnel outlet containing the inoculant is aligned with the pouring molten iron flow to sprinkle the inoculant on the molten iron flow, and is evenly added throughout the casting process, due to The lower pouring temperature is to prevent silicon segregation in the casting. To avoid excessive size and excessive addition of the inoculant, the amount of addition is controlled to 0.1%~0.15%, and the size of the funnel outlet is controlled to be φΐθ mm. In the pouring process, the pouring temperature is controlled at 1350 ° C to 1360 ° C. After the pouring process is completed, the temperature of the casting in the mold is detected, and the temperature is controlled at 850 to 880 ° C, and the air is cooled to 520 to 540 ° C. It is placed in a box containing dry sand and covered with molding sand, and then cooled to room temperature.

有益效果 Beneficial effect

[6] 本发明对传统的球墨铸铁行星架的铸造工艺进行了改进，与现有技术相比具有以下优点： [6] The present invention improves the casting process of the conventional ductile iron carrier, and has the following advantages over the prior art:

[7] 首先，在浇注***的设计中釆用兼顾了底注和顶注的阶梯浇注法，此改进使内浇道分散，金属液冲击力小，充型平稳，高温金属液在型腔上部，有利于补缩，排气，兼有顶注和底注的优点，提高了铸件的成品率。 [7] Firstly, in the design of the gating system, the step casting method with both the bottom note and the top bet is used. This improvement makes the sprue disperse, the impact of the molten metal is small, the filling is smooth, and the high temperature molten metal is in the upper part of the cavity. It is beneficial to the feeding and exhausting, and has the advantages of both top and bottom, which improves the yield of the casting.

[8] 作为本发明的一种改进，在造型工序中，本发明在铸件的厚壁部位摆放冷铁，冷铁的激冷作用强不但可防止在壁厚部位产生裂纹，减轻或防止厚壁处的偏析，还可配合冒口的使用有效防止缩孔、缩松，加强铸件的顺序凝固条件，改善铸件局部的金相组织和力学性能，提高铸件的表面硬度和耐磨性。 [8] As an improvement of the present invention, in the molding process, the present invention places cold iron on the thick-walled portion of the casting, and the chilling action of the cold iron not only prevents cracks from being generated in the wall thickness portion, but also reduces or prevents the thickness. The segregation at the wall can also be used in conjunction with the riser to effectively prevent shrinkage and shrinkage, enhance the sequential solidification conditions of the casting, improve the metallographic structure and mechanical properties of the casting, and improve the surface hardness and wear resistance of the casting.

[9] 作为本发明的一种改进，熔炼铁液工序中，本发明在铁液中加入了 Sn元素， Sn 元素是一种具有能促进形成珠光体并细化组织，能提高球墨铸铁的强度和耐磨性的元素， Sn元素稳定珠光体的能力是 Cu元素的 10倍，同吋 Cu元素和 Sn元素的组合合金化，不仅符合高质量、低成本的要求，还能够降低球墨铸铁断面的敏感性并可使在齿轮箱的厚壁处也能达到高的珠光体含量，在熔炼铁液中加入 Sn 元素可促进珠光体生成；同吋发明人由于考虑到 Sn元素是碳化物形成元素，容易使铸件材料变脆，降低材料的疲劳强度，将所述 Sn元素的加入量确定为铁液总质量的 0.015-0.02%。通过此处理，使最终产品行星架的珠光体含量达到 88% 以上。 [9] As an improvement of the present invention, in the smelting iron liquid process, the present invention adds a Sn element to the molten iron, Sn The element is an element which promotes the formation of pearlite and refines the structure, and can improve the strength and wear resistance of the ductile iron. The ability of Sn element to stabilize pearlite is 10 times that of Cu element, and the same as Cu element and Sn element. Combined alloying not only meets the requirements of high quality and low cost, but also reduces the sensitivity of the ductile iron section and enables high pearlite content in the thick wall of the gearbox. Sn element is added to the molten iron. It can promote the formation of pearlite; the same inventors consider that the Sn element is a carbide forming element, easily make the casting material brittle, reduce the fatigue strength of the material, and determine the amount of the Sn element added as 0.015 of the total mass of the molten iron. -0.02%. Through this treatment, the pearlite content of the final product carrier is over 88%.

[10] 作为本发明的另一个改进，在所述的球化工序中，本发明釆用凹坑式的处理包形式，在凹坑内球化剂能得到紧实，起爆吋间和反应速度易于控制，吸收率显著提高；球化剂的加入量根据原铁水的含 S量，选择在处理铁水质量的 1.2〜1.4% ，原铁水含硫量越高，消耗在脱硫商的球化剂越多，因此球化剂的加入量随铁水含硫量增高而加大，保证球化效果的同吋也有明显的脱硫效果；要求球化剂中含镁量较高，含稀土和硅量较低，在球化处理的铁氧液中，残留镁质量百分含量为 0.05〜0.07%，残留稀土质量百分含量为 0.02〜0.03%，残余的稀土和镁还能够促进珠光体的形成并细化珠光体，进一步有效保证本发明能够使齿轮箱含有 90%左右的珠光体；用高钙钡孕育剂、铁屑和压块生铁作为覆盖剂进行覆盖，釆用覆盖剂的目的在于避免合金裸露面过早起爆，可以使铁水盖过球化剂一定高度后才开始反应，球化剂充分与铁水作用，让球化剂平稳而均匀地通过铁水并被铁水吸收，提高球化效果，另外，由于覆盖剂的隔离作用可以避免镁和稀土与空气中氧的接触，从而防止本发明出现回硫现象。 [10] As another modification of the present invention, in the spheroidizing step, the present invention is in the form of a pit type processing package, in which the spheroidizing agent can be compacted in the pit, and the initiation time and reaction speed are easy. Control, the absorption rate is significantly improved; the amount of spheroidizing agent is selected according to the S content of the original molten iron, which is selected to be 1.2~1.4% of the quality of the treated molten iron. The higher the sulphur content of the original molten iron, the more spheroidizing agent is consumed by the desulfurizer. Therefore, the amount of the spheroidizing agent increases as the sulphur content of the molten iron increases, and the spheroidizing effect also has a significant desulfurization effect; the spheroidizing agent is required to have a high magnesium content, and the rare earth and silicon are low. In the spheroidized ferrite solution, the residual magnesium content is 0.05-0.07%, and the residual rare earth mass percentage is 0.02-0.03%. The residual rare earth and magnesium can also promote the formation of pearlite and refine the pearlescence. Further effective to ensure that the present invention can make the gear box contain about 90% of pearlite; cover with high calcium barium inoculant, iron filings and briquettes as a covering agent, and the purpose of the covering agent is to avoid alloy exposure Premature detonation, the molten iron can be passed over a certain height of the spheroidizing agent before the reaction begins. The spheroidizing agent acts well with the molten iron, allowing the spheroidizing agent to pass through the molten iron smoothly and uniformly, and is absorbed by the molten iron, thereby improving the spheroidizing effect. The barrier effect of the covering agent can prevent the contact of magnesium and rare earth with oxygen in the air, thereby preventing the occurrence of sulfur reversion in the present invention.

[11] 作为本发明的另一个改进，在所述的孕育工序中，孕育次数控制为 3次，分别是在球化反应包坑内覆盖在球化剂上面一次孕育、出水过程中出水四分之三吋的倒包二次孕育和浇注过程中的随流孕育，釆用 3次孕育可以促进球墨铸铁石墨化及分布均匀，使获得的石墨细小、圆整，孕育效果更好。 [11] As another improvement of the present invention, in the gestation process, the number of gestation times is controlled to three times, which are respectively covered in the spheroidization reaction pit, and the effluent is immersed in the effluent. The three-in-one pours are inoculated with the second inoculation and pouring, and the three times of inoculation can promote the graphitization and uniform distribution of the ductile iron, so that the obtained graphite is fine and round, and the inoculation effect is better.

[12] 作为本发明的还一个改进，在所述的浇注工序中，浇注温度控制在 1350°C〜13 60°C; 1350〜1360°C的浇注温度能够进一步保证本发明的实施可以满足力学性能的要求，还能避免气孔、夹砂等缺陷，浇注效果显著提高。 [13] 作为本发明的再一个改进，在浇注工序完成后，检测铸型内铸件温度，控制在[12] As a further improvement of the present invention, in the pouring process, the pouring temperature is controlled at 1350 ° C to 13 60 ° C; the pouring temperature of 1350 to 1360 ° C can further ensure that the implementation of the present invention can satisfy the mechanics The performance requirements can also avoid defects such as pores and sand, and the pouring effect is significantly improved. [13] As a further improvement of the present invention, after the casting process is completed, the temperature of the casting in the mold is detected, and the control is performed.

850〜880°C进行开箱，空冷至 520〜540°C，再放入盛有干砂的箱内并使用型砂进行覆盖，然后冷却至常温开箱。这样的处理基于以下原理：铸态生产方式预热处理的正火工序是将铸件在 800°C以上某一温度区间保温，本发明釆取在浇注后的齿轮箱铸件继续留在铸型内继续保温至 850〜880°C吋提早将铸件从铸型内取出的简化的正火方法，来代替传统的放入炉膛内加热保温的正火处理工艺，同吋为了去除提早开箱为铸件带来的较大的铸造应力，釆用去应力退火工序可以有效提高铸件的抗拉强度、屈服强度及硬度，使齿轮箱达的力学性能达到要求，而且这种处理方法省去了正火处理工序使本发明操作上更易实现，也使铸件不易变形，劳动强度降低，成本减少。 Unpack the box at 850~880°C, air cool to 520~540°C, put it in the box with dry sand and cover it with sand. Then cool it to room temperature. Such treatment is based on the following principles: The normalizing process of pre-heat treatment in the as-cast production mode is to keep the castings insulated at a temperature range above 800 ° C. The gearbox castings of the present invention that are drawn after casting continue to remain in the mold. Insulation to 850~880 °C, the simplified normalizing method for taking out the castings from the mold early, instead of the traditional normalizing treatment process of heating and holding in the furnace, the same as in order to remove the early unpacking for the castings The large casting stress, the use of the stress-relieving annealing process can effectively improve the tensile strength, yield strength and hardness of the casting, so that the mechanical properties of the gearbox can be achieved, and this treatment eliminates the normalizing treatment process. The invention is easier to realize in operation, and also makes the casting less deformable, labor intensity is reduced, and cost is reduced.

[14] 通过本发明的方法所铸造的球墨铸铁行星架，其金相组织的珠光体含量达到 97. [14] The ductile iron carrier cast by the method of the present invention has a metallographic structure having a pearlite content of 97.

5% , 球化率为 95% , 抗拉强度 ob达到 861MPa，屈服强度 os为 560MPa，延伸率 δ 达到 7%，硬度在 230≤ΗΒ≤270，完全符合其机械性能的要求。这样的工艺调整，不仅满足了性能要求，更在生产成本、效率上有了较大提高，每吨铸件成本节约约在 1000-2000元 /吨左右，为批量生产在热处理环节上节能降耗起到了关键作用。 5%, the spheroidization rate is 95%, the tensile strength ob reaches 861 MPa, the yield strength os is 560 MPa, the elongation δ is 7%, and the hardness is 230 ≤ ΗΒ ≤ 270, which fully meets the requirements of mechanical properties. Such process adjustment not only meets the performance requirements, but also greatly improves the production cost and efficiency. The cost per ton of castings is about 1000-2000 yuan/ton, which is energy saving and consumption reduction for mass production in heat treatment. It has played a key role.

附图说明 DRAWINGS

[15] 图 1是以珠光体为基体的金相图；从表面至中心，珠光体含量逐渐增加，铁素体量逐渐减少，珠光体含量达到 98% , 强度显著提高。 [15] Figure 1 is a metallographic diagram of pearlite as the matrix; from the surface to the center, the pearlite content gradually increases, the ferrite content decreases gradually, the pearlite content reaches 98%, and the strength increases remarkably.

[16] 图 2是以石墨为基体的金相图；从图中可见：球化良好，石墨细小、圆整； [16] Figure 2 is a metallographic diagram based on graphite; visible from the figure: good spheroidization, fine and round graphite;

[17] 图 3是本发明对行星架进行阶梯式浇注的结构示意图；从图中可见，浇注吋，从铸型的上中下同吋注入铁水，内浇道分散，充型平稳，明显提高成品率。 [17] FIG. 3 is a schematic structural view of the stepwise pouring of the planet carrier according to the present invention; as can be seen from the figure, the casting 吋, the molten iron is injected from the upper middle and lower sides of the casting mold, the inner runner is dispersed, the filling is stable, and the filling is obviously improved. Yield.

[18] 图 4是产品的珠光体含量随 Sn元素加入量变化的曲线图，从图中可见，在其他条件稳定的情况下，随 Sn加入量的增加，珠光体含量逐步提高，但 Sn加入量过多容易引起铸件材料变脆，而且 Sn加入质量百分含量在 0.018%左右吋珠光体含量已完全满足要求，故将其加入质量百分含量控制在 0.02%以下。 [18] Figure 4 is a graph showing the pearlite content of the product as a function of the amount of Sn added. It can be seen from the figure that, under other conditions, the amount of pearlite increases gradually as the amount of Sn increases, but Sn is added. Excessive amount can easily cause the casting material to become brittle, and the content of Sn added to the mass percentage is about 0.018%. The pearlite content has completely met the requirements, so the content of the added mass percentage is controlled below 0.02%.

本发明的实施方式 Embodiments of the invention

[19] 以下实施例为本发明的一些举例，不应被看做是对本发明的限定。 [20] 实施例 1 : The following examples are illustrative of the invention and are not to be construed as limiting the invention. [20] Example 1:

[21] 一种球墨铸铁行星架的铸造工艺，包括造型工序、熔炼铁液工序、球化工序、孕育工序、浇注工序、正火工序和去应力退火工序，这些工序按照本领域内常用技术进行，并在浇注工序这一步骤上作如下改进：在浇注工序中，在行星架的底盘 1和立柱 2的顶部通过 4-10根阶梯式内浇道 4同吋进行浇注。 [21] A casting process of a ductile iron carrier, comprising a molding process, a smelting iron process, a spheroidizing process, a gestation process, a casting process, a normalizing process, and a stress relief annealing process, which are performed according to techniques commonly used in the art. And in the casting step this step is improved as follows: In the casting process, the bottom of the chassis 1 and the column 2 of the planet carrier are poured through 4-10 stepped gates 4 simultaneously.

[22] 除此之外，在其他工序中作如下改进：在造型工序中，在行星架的底盘 1和立柱 2的结合部位以及底盘 1上凸台 3的两端部位摆放冷铁。在熔炼铁液工序中，铁液中加入 Sn元素，所述 Sn元素的加入质量为铁液总质量的 0.015〜0.02%。球化工序中，釆用凹坑式的处理包形式，球化剂的加入质量为铁水质量的 1.2〜1.4%，并用硅铁粉覆盖在所述球化剂表面。孕育工序中，孕育次数为三次，分别是在球化反应包坑内覆盖在球化剂上面一次孕育、出水过程中出水四分之三吋的倒包二次孕育和浇注过程中的随流孕育。浇注工序中，浇注温度控制在 1350°C〜13 60°C，浇注工序完成后，检测铸型内铸件温度，控制在 850〜880°C进行开箱，空冷至 520〜540°C，再放入盛有干砂的箱内并使用型砂进行覆盖，然后冷却至室温开箱。 [22] In addition, the following improvements are made in other processes: In the molding process, cold iron is placed on the joint portion of the chassis 1 and the column 2 of the carrier and the both ends of the boss 3 on the chassis 1. In the smelting iron liquid process, Sn element is added to the iron liquid, and the Sn element is added in an amount of 0.015 to 0.02% by mass of the total iron liquid. In the ball chemical sequence, the burr-type treatment package is used. The spheroidizing agent is added in an amount of 1.2 to 1.4% by mass of the molten iron, and is covered with the ferrosilicon powder on the surface of the spheroidizing agent. In the gestation process, the number of gestation times is three, which are in the spheroidization reaction pit, which is covered with the spheroidizing agent, and the effluent in the effluent process is immersed in the second gestation and pouring process. In the pouring process, the pouring temperature is controlled at 1350 ° C to 13 60 ° C. After the pouring process is completed, the temperature of the casting in the mold is detected, and the control is carried out at 850 to 880 ° C, and the air is cooled to 520 to 540 ° C, and then placed. Into the box containing dry sand and cover with sand, then cool to room temperature to open the box.

[23] 实施例 2: [23] Example 2:

[24] 本发明涉及的是一种齿轮箱用球墨铸铁行星架的生产工艺，工艺过程包括造型工序、熔炼铁液工序、球化工序、孕育工序、浇注工序、正火工序、应力退火工序。 [24] The present invention relates to a production process of a ductile iron carrier for a gearbox, the process comprising a molding process, a smelting molten iron process, a spheroidizing process, a gestation process, a casting process, a normalizing process, and a stress annealing process.

[25] 造型工序：釆用树脂砂造型，砂的配制上，砂、树脂和固化剂的比例控制在 40 0： 4： 1的比例，砂温控制在 30°C。模具摆放吋，在行星架厚壁和急剧变化部位摆放冷铁与釆用阶梯式浇注***的工艺，冷铁摆放位置和浇注***设计见附图 3 ，模具摆放完毕放砂吋，砂流量要大，控制为 100Kg/30s的速度。 [25] Modeling process: 树脂 Resin sand molding, sand preparation, sand, resin and curing agent ratio is controlled at 40 0: 4: 1 ratio, sand temperature is controlled at 30 °C. After the mold is placed, the process of placing the cold iron and the stepped pouring system on the thick wall and the sharply changing part of the planet carrier, the layout of the cold iron and the design of the pouring system are shown in Figure 3, and the mold is placed and placed in the sand. The sand flow rate is large, and the speed is controlled to 100Kg/30s.

[26] 熔炼铁液工序：用于熔炼铁液的原料有生铁（质量百分含量 50%) 、废钢（质量百分含量 40%) 和 QT700回炉料（质量百分含量 10%) ，加料顺序为生铁、废钢和回炉料，经调质生化、调质、脱硫、增碳和处理后，熔炼后所述铁液成分各元素的质量百分含量分别控制在如下范围内： C质量百分含量为 3.55%〜3.65% ； Si质量百分含量为 2.05%〜2.15%； Mn质量百分含量为 0.025%〜0.029%； P质量百分含量为≤0.025% ; S质量百分含量为 0.008%〜0.012%； Cu质量百分含量为 0.33%— 0.37%； Sn质量百分含量为 0.015-0.02% ; 碳当量为 CE=4.25%〜4.35%。 S n元素可促进珠光体生成；同吋由于 Sn元素是碳化物形成元素，容易使铸件材料变脆，降低材料的疲劳强度，将所述 Sn元素的加入量确定为铁液总质量的 0.015- 0.02%。通过此处理，使最终产品行星架的珠光体含量达到 88%以上。 [26] Smelting of molten iron: The raw materials used for smelting molten iron are pig iron (50% by mass), scrap (40% by mass) and QT700 (10% by mass), feeding sequence For pig iron, scrap steel and recycled materials, after quenching and tempering, quenching, desulfurization, carbonation and treatment, the mass percentage of each element of the iron component after smelting is controlled within the following range: C mass percentage It is 3.55%~3.65%; the mass percentage of Si is 2.05%~2.15%; the mass percentage of Mn is 0.025%~0.029%; The content percentage is ≤0.025%; the S mass percentage is 0.008%~0.012%; the Cu mass percentage is 0.33%-0.37%; the Sn mass percentage is 0.015-10.02%; the carbon equivalent is CE=4.25. %~4.35%. The Sn element can promote the formation of pearlite; while the Sn element is a carbide forming element, it is easy to make the casting material brittle and reduce the fatigue strength of the material, and the amount of the Sn element is determined to be 0.015 of the total mass of the molten iron. 0.02%. Through this treatment, the pearlite content of the final product carrier is 88% or more.

[27] 球化工序：釆用凹坑式的处理包形式，凹坑式的处理包形式是指球化处理包底部分为高低不平的两部分，剖切面呈阶梯形状，其中凹坑的面积占包底的 2/5〜1 /2，凹深按容纳处理满包铁水所需的球化剂量而定。在处理阶段进行球化处理，球化剂的加入质量控制在总处理铁水质量的 1.2〜 1.4%，铁液冲入包坑内的流量要控制的比较大，保证球化后铁液中残留镁的质量百分含量为 0.05〜0.07%，残留稀土的质量百分含量为 0.02〜0.03%；同吋，加入球化剂后，在其表面覆盖高钙钡孕育剂、铁屑和压块生铁作为覆盖剂进行覆盖，以此使球化剂充分与铁水作用，让球化剂平稳而均匀地通过铁水并被铁水吸收，提高球化效果。 [27] Spheroidization process: In the form of a pit-type processing package, the pit-type processing package form refers to the two parts of the bottom of the spheroidizing treatment package, which are divided into high and low, and the cut surface is in a stepped shape, wherein the area of the pit It occupies 2/5~1 /2 of the bottom of the package, and the concave depth depends on the spheroidizing dose required to process the full package of molten iron. Spheroidizing treatment in the treatment stage, the quality of the addition of the spheroidizing agent is controlled to 1.2~1.4% of the total treated molten iron mass, and the flow rate of the molten iron into the pit is controlled to ensure the residual magnesium in the molten iron after spheroidization. The mass percentage is 0.05~0.07%, and the residual rare earth mass percentage is 0.02~0.03%. In the same way, after adding the spheroidizing agent, the surface is covered with high calcium strontium inoculant, iron filings and briquetting pig iron as cover. The agent is covered, so that the spheroidizing agent acts well with the molten iron, and the spheroidizing agent is smoothly and evenly passed through the molten iron and absorbed by the molten iron, thereby improving the spheroidizing effect.

[28] 孕育工艺：孕育目的是促使形成结晶核心以改善金属组织和物理、力学性能，促进石墨化的同吋抑制渗碳体的生成。为此本实例严格按本发明所述釆取 3次孕育的方法来实施，在球化反应包坑内覆盖在球化剂上面一次孕育、出水过程中出水四分之三吋的倒包二次孕育和浇注过程中的随流孕育，釆用 3次孕育可以促进球墨铸铁石墨化及分布均匀，使获得的石墨细小、圆整，孕育效果更好。此孕育方法一方面防止了孕育衰退改善了孕育效果，另一方面冶防止了形成碳化物和浇注后冷却过程中出现气孔。 [28] Inoculation process: The purpose of gestation is to promote the formation of crystalline core to improve metal structure and physical and mechanical properties, and promote the formation of graphitization to inhibit the formation of cementite. To this end, the present example is strictly carried out according to the method of gestation of the invention according to the present invention. The spheroidization reaction pit is covered with a double-injection of three-quarters of the effluent in the priming and effluent process. And with the flow in the pouring process, the use of 3 times of gestation can promote the graphitization and uniform distribution of the ductile iron, so that the obtained graphite is small, round, and better in conception. On the one hand, this method of preventing the growth of the recession improves the inoculation effect, and on the other hand, prevents the formation of carbonaceous material and the occurrence of pores in the cooling process after pouring.

[29] 浇注工序：处理后的成分达到规定值后开始进行浇注，浇注温度控制在 1350°C 〜1360°C，釆用阶梯式浇注***，此工序可控性很强，行动要迅速，在孕育处理后迅速扒渣、浇注，这样做的目的是防止产生气孔，使充型平稳，保证浇注效果。 [29] Casting process: After the treated components reach the specified value, the pouring is started. The pouring temperature is controlled at 1350 ° C to 1360 ° C. The step casting system is adopted. This process is very controllable and the action is rapid. After the gestation treatment, the slag is quickly poured and poured. The purpose of this is to prevent the generation of pores, to make the filling smooth, and to ensure the pouring effect.

[30] 在本实例的浇注工序完成后，检测铸型内铸件温度，控制在 850〜880°C进行开箱，空冷至 520〜540°C，再放入盛有干砂的砂箱内并使用型砂进行覆盖，然后冷却至常温开箱。在铸态下，釆用提早开箱的方法来实现正火处理工序，在简化热处理工序的同吋直接取得牌号 QT700-2的力学性能要求和金相组织标准的球墨铸铁件，同吋由于此改进使热处理工艺得到简化而节约了热处理吋的能源消耗，此种处理方法显著节约能耗，减少工序，缩短生产周期，降低废品率和降低成本等一系列优点，这也是作为铸造工作者的我们追求的目标之一。 [30] After the casting process of this example is completed, the temperature of the casting in the mold is detected, and the control is carried out at 850 to 880 ° C, and the air is cooled to 520 to 540 ° C, and then placed in a sand box containing dry sand. Cover with sand and then cool to room temperature. In the as-cast condition, the method of pre-opening the box to achieve the normalizing treatment process, directly obtaining the mechanical properties of the grade QT700-2 and the standard of the metallographic organization in the simplified heat treatment process Cast iron parts, the same as this improvement, the heat treatment process is simplified and the energy consumption of the heat treatment is saved. This treatment method significantly saves energy consumption, reduces processes, shortens production cycle, reduces scrap rate and reduces cost. It is also one of our goals as a foundry worker.

[31] 经过本发明的工艺流程，通过对各工序仔细操作和熔炼过程的严格控制，本实例熔炼后铁液中最终实际成分均控制在发明要求的范围内，即如下： C质量百分含量为 3.63% ; Si质量百分含量为 2.11%; Mn质量百分含量为 0.239% ; P质量百分含量为 0.023% ; S质量百分含量为 0.011%; Cu质量百分含量为 0.033% ; Sn质量百分含量为 0.018%。本实例中生产的球墨铸铁件达到的力学性能如下表中所示。序号检验项目单位技术要求检验结果评价 [31] After the process of the present invention, through careful control of each process and strict control of the smelting process, the final actual components in the molten iron after the smelting of the present example are controlled within the scope of the invention, namely as follows: C mass percentage 3.63%; Si mass percentage is 2.11%; Mn mass percentage is 0.239%; P mass percentage is 0.023%; S mass percentage is 0.011%; Cu mass percentage is 0.033%; Sn The mass percentage is 0.018%. The mechanical properties achieved by the ductile iron castings produced in this example are shown in the following table. No. Inspection item Unit Technical requirements Inspection result Evaluation

1 抗拉强度 MPa >700 975 合格1 Tensile strength MPa >700 975 Qualified

2 屈服强度 MPa >420 600 合格2 Yield strength MPa >420 600 qualified

3 伸长率 % >2 6.0 合格3 Elongation % >2 6.0 Qualified

4 硬度 HB 225〜305 290 合格4 hardness HB 225~305 290 qualified

5 球化率 % 金相制样后球化级别：合格 5 Spheroidization rate % After metallographic preparation Spheroidization level: Qualified

100倍下观 2级，球化 100 times down, level 2, spheroidization

察率为 94% The inspection rate is 94%

6 珠光体含量 % 经 30%硝酸 98% 合格 6 Pearlite content % Passed 30% nitric acid 98% qualified

酒精浸蚀后 After alcohol etch

500倍下观 500 times down

察 Inspect

Claims

权利要求书 Claim

[Claim 1] 一种球墨铸铁行星架的铸造工艺，包括造型工序、熔炼铁液工序、球化工序、孕育工序、浇注工序、正火工序和去应力退火工序，其特征在于：所述浇注工序中，在行星架的底盘（1 ) 和立柱 2) 的顶部通过 4- 10根阶梯式内浇道 (4) 同吋进行浇注。 [Claim 1] A casting process of a ductile iron carrier, comprising a molding process, a smelting iron process, a spheroidizing process, a gestation process, a casting process, a normalizing process, and a stress relief annealing process, wherein: the casting process In the top of the chassis (1) and column 2) of the planet carrier, it is poured through 4-10 stepped gates (4).

[Claim 2] 根据权利要求 1所述球墨铸铁行星架的铸造工艺，其特征在于在所述造型工序中，在行星架的底盘（1 ) 和立柱（2) 的结合部位以及底盘（1 ) 上凸台（3) 的两端部位摆放冷铁。 [Claim 2] The casting process of the ductile iron carrier according to claim 1, characterized in that in the molding process, on the joint portion of the chassis (1) and the column (2) of the carrier and the chassis (1) Place cold iron on both ends of the boss (3).

[Claim 3] 根据权利要求 1所述球墨铸铁行星架的铸造工艺，其特征在于在所述熔炼铁液工序中，铁液中加入 Sn元素，所述 Sn元素的加入质量为铁液总质量的 0.015〜0.02%。 [Claim 3] The casting process of the ductile iron carrier according to claim 1, characterized in that in the smelting molten iron process, Sn element is added to the molten iron, and the mass of the Sn element added is the total mass of the molten iron 0.015~0.02%.

[Claim 4] 根据权利要求 1所述球墨铸铁行星架的铸造工艺，其特征在于在所述球化工序中，釆用凹坑式的处理包形式，球化剂的加入质量为铁水质量的 1.2〜 1.4% , 并用硅铁粉覆盖在所述球化剂表面。 [Claim 4] The casting process of the ductile iron carrier according to claim 1, wherein in the spheroidizing step, the sputum is in the form of a pit type processing package, and the spheroidizing agent is added in a mass of 1.2 by mass of the molten iron. ~ 1.4%, and covered with silicate powder on the surface of the spheroidizing agent.

[Claim 5] 根据权利要求 1所述球墨铸铁行星架的铸造工艺，其特征在于在所述孕育工序中，孕育次数为三次，分别是在球化反应包坑内覆盖在球化剂上面一次孕育、出水过程中出水四分之三吋的倒包二次孕育和浇注过程中的随流孕育。 [Claim 5] The casting process of the ductile iron carrier according to claim 1, wherein in the inoculation process, the number of times of breeding is three times, and the spheroidizing reaction pit is covered with the spheroidizing agent once, In the process of effluent, three-quarters of the effluent of the effluent is immersed in the second gestation and pouring process.

[Claim 6] 根据权利要求 1所述球墨铸铁行星架的铸造工艺，其特征在于所述的浇注工序中，浇注温度控制在 1350°C〜1360°C，浇注工序完成后，检测铸型内铸件温度，控制在 850〜880°C进行开箱，空冷至 5 20〜540°C，再放入盛有干砂的箱内并使用型砂进行覆盖，然后冷却至室温开箱。 [Claim 6] The casting process of the ductile iron carrier according to claim 1, characterized in that in the pouring step, the pouring temperature is controlled at 1350 ° C to 1360 ° C, and after the casting process is completed, the casting in the casting is detected The temperature is controlled to be unpacked at 850 to 880 ° C, air cooled to 5 20 to 540 ° C, placed in a box containing dry sand and covered with molding sand, and then cooled to room temperature to open the box.