Is it Bi-directional?

Yes

no

Yes

Yes

Yes

Can it be used for high   concentration and high hardness granular media

Yes

no

no

no

no

Can it be used in high   crystalline media?

Yes

no

no

no

no

Is there any friction   during opening and closing?

No

Yes

No

No

Yes

Is there a long life   soft and metal double sealing function?

Yes

no

no

no

no

Can it cut fiber?

Yes

no

no

no

no

Does it have a valve   scale prevention function?

Yes

no

no

Yes

Yes

Does it have automatic   compensation gap function?

Yes

Yes

Yes

no

no

Does it have automatic   compensation for wear caused by long-term use?

Yes

no

Yes

no

Yes

Is there a small size,   high installation height, low weight, easy to make insulation materials,   energy saving and environmental protection advantages?

Yes

Yes

no

no

no