热芯盒排气

Hot core box exhaust

热芯盒排气的作用有两方面：

There are two aspects of the effect of the exhaust of the hot core box.

（一）是保证射砂时芯盒内空气能够顺利及时排出。

(1) ensure that the air in the core box can be discharged smoothly and timely.

（二）是引导射入砂流的充填方向。正确的设计排气装置对获得紧实度均匀，表面光洁的砂芯是很重要的。

(two) the direction of filling the sand flow. The correct design of the exhaust device is very important for obtaining uniform core and smooth core.

芯盒排气位置应选择在：芯盒蹩气的死角、芯盒最后充填部分、芯盒转角或砂流不易达到的狭长通道处、分型面处、多射孔的芯盒中砂流干扰处等。根据生产经验，芯盒的总排气面积至少应等于射砂孔总面积的0.1～0.2倍。在生产中往往根据上述原则预先确定排气位置，经试射后，根据砂芯各部紧实度再予以调整。

The exhaust position of the core box should be selected as the dead angle of the core box, the last filling part of the core box, the corner of the core box or the narrow and long channel where the sand flow is not easy to reach, and the sand flow interference in the core box of multi perforation. According to the production experience, the total exhaust area of the core box should be at least 0.1 to 0.2 times the total area of the sand hole. In the process of production, the exhaust position is determined in advance according to the above principles, and then adjusted according to the compactness of each core of the sand core after being tested.

热芯盒的排气方式有：排气塞排气、排气槽排气和活块排气。

The exhaust modes of the hot box are: exhaust plug exhaust, exhaust vent exhaust and live block exhaust.

1.排气塞排气：是利用尺寸大小不同的排气塞，装在芯盒内表面 处，其后连通排气孔，使气体排除。排气塞目前有三种结构。一般排气塞可以用铜或钢经切削加工而成，也可用铜合金、铝合金等压铸而成，这种排气塞主要缺点是容易堵塞，不易清理。网筛排气塞是用不锈钢丝或镍铬丝制成筛网。因为网筛有弹性，因此效果较好不易堵塞。缝隙式排气塞是用0.3～0.4毫米的不锈钢板，经光刻或腐蚀加工出0.3~0.4毫米的缝隙，具有良好的效果。 用排气塞的优点是：排气面积大，安装灵活。

1. exhaust plug exhaust: it is the use of different sizes of exhaust plug, mounted inside the core box surface, and then connected to the exhaust hole, so that gas removal. There are three structures in the exhaust plug. The general exhaust plug can be machined with copper or steel, and can also be made of copper alloy and aluminum alloy. The main disadvantage of the exhaust plug is that it is easy to block and not easy to clean up. The screen plug is made of stainless steel wire or nickel chromium wire. Because the screen is elastic, it has better effect and is not easy to jam. The slit type exhaust plug is made of 0.3 ~ 0.4 millimeter stainless steel plates, and has a 0.3~0.4 millimeter gap through lithography or corrosion. The advantages of the exhaust plug are: large exhaust area and flexible installation.

2.排气槽排气：利用分型面、射砂面、镶块以及底板等结合面开设排气槽 进行排气。排气槽的深度应根据使用芯砂的粒度而定。以排气不跑砂为原则。一般靠近芯子表面槽深，出口端可扩大为1毫米。槽宽根据需要决定，常用10~15毫米。也可与总通气槽相通，使气体排到外面。但是应注意：对于多腔芯盒，各腔的排气槽不应串通，以免两腔串气互相影响，造成紧实度不均或不成型。

2. exhaust venting: using exhaust manifold for parting surface, shooting sand surface, insert block and bottom plate for exhaust. The depth of the exhaust tank should be determined according to the size of the core sand. The principle of not running sand by exhaust. Generally, the groove is deep near the core surface, and the outlet end can be expanded to 1 millimeters. The width of the slot is determined according to the need, and 10~15 millimeter is commonly used. It can also communicate with the total ventilation tank to drain the gas outside. However, it should be noted that for the multi cavity box, the exhaust grooves of each cavity should not be colluded, so as not to affect the two chamber collusion, resulting in uneven or uncompaction.

3.间隙排气：在芯盒本体与活块、顶杆间的配合面上制做间隙（约为0.1- 0.3毫米）进行排气。采用活块与芯盒本体结合的间隙进行排气。为了使气体顺利排除，须在活块背后的芯盒壁上钻出排气孔。排气间隙制造容易，应用可靠，也是经常采用的一种排气方法。

3. clearance exhaust: the gap between the core box body and the live block and ejector pin is made on the mating surface (about 0.1- 0.3 mm) for exhausting. The gap between the live block and the core box body is used for exhausting. In order to remove the gas smoothly, exhaust holes should be drilled on the core box wall behind the live block. The exhaust gap is easy to manufacture and reliable. It is also a commonly used exhaust method.