| TYPE |
External Joint(Wooyang Product) |
internal Joint(Other Company Product) |
| resistance of the air |
As the joint support fixture is located in outside, there is no resistance to air flow and no noise. |
Joint support fixture & duct support fixture located in internal part. So It has huge resistance to air flow. |
| Noise |
Dust consist of circular thin plates. It has slippery inside, joints located in external so there is no noise caused by the air resistance |
Duct has flexible hose, joint support fixture & dust support fixture located in internal part So It has huge resistance to air flow and big noise. |
| Life |
there is no resistance to air flow and no noise. |
Inner part of duct has joint and support fixture so it pile up Foreign substance. |
| replacement of material |
It can manufacture replacing SUS & PP for strong acidic work |
Because of foreign substance, Life is short and has frequent breakdown. It has corrosion risk |
Elbow is on the outside, so there is no air resistance and noise. 
Hood is designed to control the resistance of the warm current, because hood was made in slot type to raise speed high. 
