DYQ340H-16Top mounted eccentric hemispherical valve uses eccentric valve body, eccentric ball and valve seat. When the valve rod rotates, it will automatically center in the common track. The closer it is closed, the tighter it will be, and the better sealing effect can be achieved. The ball and valve seat of the valve are completely separated, which eliminates the wear of the sealing ring and overcomes the problem that the traditional ball valve seat and the sealing surface of the ball are always worn. The non-metallic elastic material is embedded in the metal seat, and the metal surface of the valve seat is well protected. This product is especially suitable for steel industry, aluminum industry, fiber, small solid particles, pulp, coal ash, petroleum gas and other media.

It can be widely used in water supply and drainage, sewage treatment, petroleum, chemical industry, metallurgy, electric power and other medium and low pressure pipelines, especially for the cut-off and throttling function in the fluid medium pipelines containing impurities and granular impurities

 

The valve adopts double eccentric structure, and uses the wedging effect of eccentric wheel to realize the closing and opening of sealing pair, so as to realize reliable sealing specific pressure and quick opening. Its advantages are as follows:
1. Due to the eccentric structure, the rotation radius of all points on the sealing spherical surface is different. When the sealing valve seat is closed, the closer the valve seat is, the more tight the sealing pressure is. The two-way sealing effect is excellent.
2. The valve disc adopts the full round straight through type, and has a full flow structure after opening, which has good liquidity and linear regulation performance.
3. In the process of long-term use, a new seal can be obtained by adjusting the seal ring pressing sleeve and the sealing spherical surface moving forward.
4. The operating force of the valve only acts on the minimum angle of opening or closing of the valve. When opening, the operating force decreases rapidly with the decrease of sealing specific pressure, and the sealing surface tends to be wear-free.
5. The circular flow channel has a full flow section after the valve is fully opened, and the bottom is a circular streamline structure. The deposited debris will be taken away with the flow of medium. During the closing process, the dirt deposited on the sealing surface can be removed by itself
Scale without affecting the seal.
6. The valve shaft adopts the upper and lower half shaft design, and is equipped with self-lubricating shaft sleeve. During the opening process of the valve, the friction resistance is small and the opening and closing is flexible. The unique "0" ring and the floating shaft seal replace the original butterfly valve
The packing is easy to open in the sealing process

DYQ340H-16Design of top mounted eccentric hemisphere valve: gb12237-89
Flange connection: GB / t17241.6-1998, GB / t9115 (steel)
Structural length: gb12221-89

ASTM

A194 2H

A194-8

A194-8M

A194-4

Valve body and cover	GB	WCB		ZG08Cr18Ni9		ZG08Cr18Ni12Mo2			ZG18Cr1Mo1V
	ASTM	WCB		CF8		CF8M			WC9
sphere	GB	WCB	nitridation     polishing	08Cr18Ni9	DB12     polishing	08CR18Ni12Mo2		DB12     polishing	08Cr18Ni9	D812     polishing
	ASTM	WCB		304		316			304
Stem	GB	2Cr13		08Cr18Ni9		08Cr18Ni12Mo2			25CrMo1V
	ASTM	1420		304		316			F22a
valve seat	GB	2Cc13	D507Mo   PTFE、PPL	08Cr18Ni9	D802   PTFE、PP	08Cr18Ni12Mo2	D802     PTFE、PPL		25CrMo1V		D802     PTFE、PPL
	ASTM	420		304		316			F22a
filler	GB	Flexible graphite
	ASTM	Flexible graphite
	GB	35CrMoA		08Cr18Ni9		08Cr18Ni12Mo2			25Cr2Mo1V
	ASTM	A193 B7		A320-B8		A193-B8M			F22a
Nut	GB	45		08Cr18Ni9		08Cr18Ni12Mo2			20CrMo