needed to ensure Mapleton could continue to compete. Re-engineering the main molding line to be more flexible was just one step in a multi-generation transformation plan. Recasting the plant’s “key core” system (a coremaking process that utilizes a single core to lock together a larger package) was the next step. “We were making blocks on the key core that were 10 to
18 liters, weighing a maximum of 750 lbs.,” Bevilacqua said. “We needed to increase capacity on our large blocks (up to 9,000 lbs). As opposed to making a cope and drag, we make the new molds like a loaf of bread.” For about one quarter of the cost of a new line, Maple-
ton transformed the equipment into an automated flaskless production line for large blocks. Remaining on the line are the sand dispensing system, mold dip operation, drying oven and automated handling equipment. Individual cores in the old system weighed up to 200 lbs. Now, the cores can weigh up to 2,000 lbs. Te line makes coldbox cores for cylinder block mold segments and arranges them in a vertical orienta- tion. Te heel segments for all the blocks are identical. Te middle segment design and number depends on the number of cylinders on the block (eight to 20). “We were trying to do things at the minimum invest-
ment,” Bevilacqua said. “A lot of the key core investments still had life to them.” Beginning in January 2010, the line began production on
gray and ductile iron blocks for Caterpillar’s 3500 and C175 platforms. In addition to the re-engineered key core line, Mapleton still has two manual molding areas for large blocks and miscellaneous large castings up to 25,000 lbs. “At Caterpillar, core [metalcasting] expertise in the engine group is critical to our success,” Bevilacqua said.
Other Improvements First, it was “molding line 1.” Ten, it was a “dead asset.”
Now, the re-engineered cope and drag line is a key produc- tion asset in the Mapleton plant known as the “flex line.” One of the reasons the line is flexible is a new pouring system the plant has installed. Te spider-like contraption allows Mapleton to pour molds at any height and with any iron it chooses, be it gray iron or ladle-treated ductile iron or CGI. Today, the once completely gray iron Mapleton plant pours 13% treated iron parts. “Te new pouring system offers a 3-ft. window height-
wise,” said Gary McCoy, group manager for cylinder heads. “Te mold package can vary substantially, and we have the ability to put the pouring location anywhere in a cube that would be 3-ft. high by about the width of the flask by about half of the depth.” Mapleton’s CGI capabilities were developed entirely in-
house. Rather than use an outside firm to control its metal- lurgy, Mapleton relies on tight parameters in melting, treats the iron based on chemistry, performs a nondestructive test on each ladle and pours only if the CGI quality is confirmed. “It is a ladle treatment process fundamentally devel- oped in-house,” Bevilacqua said. “As with any CGI process, it is challenging.”
“我们在10至18升的关键芯上制造缸体，最大的重 达750磅。”Bevilacqua说。 “我们需要提高我们的大 缸体的容量（高达9000磅）。与上箱和下箱不同，我们 像做面包一样做新砂型。“
只用新生产线成本的四分之一，Mapleton将设备改 造成了大型缸体无箱生产线自动化设备。砂子分配系 统、砂型下降系统、烘干炉和自动处理设备仍然留在生 产线上。在旧体系中的单个砂芯重达200磅。现在，砂 芯可重达2,000磅。生产线为缸体砂型部分制作冷芯盒 砂芯，并在垂直方向上安放。所有缸体柱脚部分是相 同的。中段的设计和数量取决于缸体的汽缸数（8至20 ） 。
“我们试图以最小的投资做事情，”Bevilacqua 说。“很多关键核心投资仍然具有生命力。” 从2010年1月开始，该生产线开始生产卡特彼勒公司 3500和C175平台的灰铁和球墨铸铁缸体。除了重新设 计的关键砂芯生产线外，Mapleton仍然有两个手工造 型区用于生产重达25,000磅的大型缸体和其它类大型铸 件。
在卡特彼勒，在发动机团队的砂芯技术是我们成功的 关键，”Bevilacqua说 。
其它改进
首先是“造型线1” 。然后，它是一个“死资产”。 现在，重新设计的上箱和下箱生产线在Mapleton厂被 称为“柔性线”的主要生产资产。该生产线灵活的原因 之一是该厂安装了新的浇注系统。 蜘蛛状的奇妙设备允许Mapleton工厂在任何高度浇 注任何铸铁：灰铸铁或包内处理的球墨铸铁或蠕墨铸 铁。如今， 一次改造完成的Mapleton工厂浇注了13％ 的处理后的灰铁件。
“新的浇注系统提供了一个3英尺的高度智能窗 口。” 缸盖组经理麦科伊加里说。 “砂型可以有很大 的差别，而我们有能力在一个3英尺高X砂型宽度X半个 长度的立方体空间中任意浇注”。 Mapleton的蠕墨铸铁功能完全在内部开 发。Mapleton依靠严格控制熔化参数，化学处理铁 液，执行对每包的无损检测并且只有确认蠕墨铸铁质量 后才进行浇注，而不是通过外部公司来控制其冶金。 “这是一个完全自主开发的包内处理过程，”
Bevilacqua说 。 “正如任何蠕墨铸铁进程，这是一项 挑战。” Mapleton同样对复杂的零件快速原型，提供砂型和 砂芯切削加工能力进行了投资。
46 |
FOUNDRY-PLANET.COM | MODERN CASTING | CHINA FOUNDRY ASSOCIATION Winter 2012
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68