熱芯盒排氣

Hot core box exhaust

熱芯盒排氣的作用有兩方面：

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

（一）是保證射砂時芯盒內(nèi)空氣能夠順利及時排出。

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

（二）是引導(dǎo)射入砂流的充填方向。正確的設(shè)計排氣裝置對獲得緊實度均勻，表面光潔的砂芯是很重要的。

(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.

芯盒排氣位置應(yīng)選擇在：芯盒蹩氣的死角、芯盒最后充填部分、芯盒轉(zhuǎn)角或砂流不易達到的狹長通道處、分型面處、多射孔的芯盒中砂流干擾處等。根據(jù)生產(chǎn)經(jīng)驗，芯盒的總排氣面積至少應(yīng)等于射砂孔總面積的0.1～0.2倍。在生產(chǎn)中往往根據(jù)上述原則預(yù)先確定排氣位置，經(jīng)試射后，根據(jù)砂芯各部緊實度再予以調(diào)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.

熱芯盒的排氣方式有：排氣塞排氣、排氣槽排氣和活塊排氣。

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

1.排氣塞排氣：是利用尺寸大小不同的排氣塞，裝在芯盒內(nèi)表面 處，其后連通排氣孔，使氣體排除。排氣塞目前有三種結(jié)構(gòu)。一般排氣塞可以用銅或鋼經(jīng)切削加工而成，也可用銅合金、鋁合金等壓鑄而成，這種排氣塞主要缺點是容易堵塞，不易清理。網(wǎng)篩排氣塞是用不銹鋼絲或鎳鉻絲制成篩網(wǎng)。因為網(wǎng)篩有彈性，因此效果較好不易堵塞。縫隙式排氣塞是用0.3～0.4毫米的不銹鋼板，經(jīng)光刻或腐蝕加工出0.3~0.4毫米的縫隙，具有良好的效果。 用排氣塞的優(yōu)點是：排氣面積大，安裝靈活。

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.排氣槽排氣：利用分型面、射砂面、鑲塊以及底板等結(jié)合面開設(shè)排氣槽 進行排氣。排氣槽的深度應(yīng)根據(jù)使用芯砂的粒度而定。以排氣不跑砂為原則。一般靠近芯子表面槽深，出口端可擴大為1毫米。槽寬根據(jù)需要決定，常用10~15毫米。也可與總通氣槽相通，使氣體排到外面。但是應(yīng)注意：對于多腔芯盒，各腔的排氣槽不應(yīng)串通，以免兩腔串氣互相影響，造成緊實度不均或不成型。

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.間隙排氣：在芯盒本體與活塊、頂桿間的配合面上制做間隙（約為0.1- 0.3毫米）進行排氣。采用活塊與芯盒本體結(jié)合的間隙進行排氣。為了使氣體順利排除，須在活塊背后的芯盒壁上鉆出排氣孔。排氣間隙制造容易，應(yīng)用可靠，也是經(jīng)常采用的一種排氣方法。

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.