Hydraulic control valve is a general title of one series control valve, was made earlier in Ireland, Holland, Demark, UAS, and Canada etc. and introduced into China in 1900s. The hydraulic control valve series made in our company cover remote control floating valve, adjustable pressure reducing valve, slowly closing check valve, pressure discharge/sustaining valve, electric valve, water pump control valve, pressure differential balancing valve, emergent closing valve, raining valve, water level fixing valve etc. And they are used in the pipe network of buildings, fire-fighting, water works, warming, steel & iron, electric power, petroleum, chemical industry systems etc.

This series valves are formed by such a way as utilizing the hydraulic control principle and the pressure differential between both upper and lower valve cavities to control the disc's movement, acting as different functions via the by-pass pipelines and the pilot valves of various different structures.

1. In 2001, the hydraulic control valves made in this Co. were entitled as the most advanced products nationwide approved by both Scientific Commission and Construction Commission of Shanghai. The appraisal number: 2001-6133.
2. In 2002, our company was entrusted by the office of Shanghai Engineering Construction Standardization to draw out SJ series hydraulic control valves' installation figure collection of the recommended application figure collection of Shanghai buildings' products, the figure collection number: 2002 HU S/T-104.
3. In 2002, our company is entrusted by the Association of China Engineering Construction Standardization to draw out the standards for the application and design rules of hydraulic control valves. The standard number: CECS144: 2002.
4. In 2004, our company is entrusted by the office of China Engineering Construction Standardization to draw out the industrial standards for the hydraulic control valves (coming soon).

1. The body is full-channel and streamlines pattern design,leaving small fluid resistance and big flow.
2. Both outside and inside of the body and bonnet are coated with epoxy resin powder which can prevent them from corrosion.
3. Using the advanced foreign know-how of removable seat ring realizes its exquisite structure, easy repair and replacement (no need to remove the whole valve).
4. It can be mounted vertically or horizontally in the pipeline with the reliability unchanged.
5. A dual protection of sealing pad and sealing ring is used on the connections between body, bonnet and piston cylinder.
6. As for the piston cylinder, a flow-guide hole is set and appropriate damper is added with it so as to have the piston movement more stable and flexible.
7. The complete combination of full stainless steel piston cylinder, overall piston and NBR seal ring makes the duration greatly extended.

Type	Diaphragm type		Piton type
	Part	Materials	Part	Materials
1	Bonnet	Casting pig, Duct alloy, Carbon steel, S.S.	Bonnet	Casting pig, Ducally, Carbon steel, S.S.
2	Spring	Spring steel, S.S.	Cylinder sleeve	S.S.
3	Pressboard of Diaphragm	Casting pig, Duct alloy, Carbon steel, SS	Piston	Duct alloy
4	Diaphragm	Acrylonitrile nylon reinforced rubber, ternary ethylene propylene nylon reinforced rubber	Seal ring	NBR, ternary ethylene propylene rubber
5	Stem	2Cr13、2Cr13,SS	Stem	2Cr13、2Cr,SS
6	Disc	Casting pig, Duct alloy, Carbon steel, copper, SS	Spring	Spring steel, SS
7	O-ring	NBR, ternary ethylene propylene rubber	Disc	Casting pig, Duct alloy. Carbon steel, SS
8	Pressboard of O-ring	Casting pig, Duct alloy, Carbon steel, SS	Sealing pad	NBR, ternary Ethylene propylene rubber
9	Seat ring	Cu-alloy, SS	Seat ring	Cu-alloy, SS
10	Body	Casting pig, Duct alloy, Carbon steel, SS	Seal pressboard	Casting pig, Duct alloy, Carbon steel, SS
11			Body	Cast iron, Duct alloy, Carbon steel body

Nominal pressure		1.0	1.6	2.5
Test pressure	Shell strength	1.5	2.4	3.75
	Air-proof Capability	1.1	1.76	2.75
NPS nominal diameter		Diaphragm type:50~450 ; Piston type:500~800
Available		Water or water-like medium
Working temperature		≤80

The internal beard on both bonnet and body is positioned via the outer circle of the piston to make sure the disc, piston and indicating rod concentric and the disc move freely so as to improve the sensibility of the main valve such as the piston type hydraulic control valve can also work reliably even if in the condition of the small flow or pressure fluctuation. To get no leak on the connections between the body, bonnet and piston cylinder, an elastic pad and NBR seal ring are used separately on the connection between the lower part of the piston and body, and between the upper part of the piston and the bonnet. (Refers to seeks a)

To produce a pressure differential between both upper and lower parts of the disc, the piston's area must be bigger than that of the disc; however this makes the piston area of a big-aperture valve very big, resulting in poor operation stability. For this valve, a flow-guide hole is designed on the piston bottom and an appropriate damper is added to the disc movement to have the disc move more reliably, thus improve the reliability of it and reduce failure occurrence frequency. The flow-guide holes are evenly distributed on the plane of the piston cylinder bottom and the hole's quantity and size are depended on the size of the valve aperture. (Refers to seeks b)

A processed face of a certain witch on the body's neck is matched with the outer circle of the stainless steel piston cylinder to make the cylinder fixed stably inside the body; the piston with dual seal rings moves up and down along with the ground internal wall of the cylinder and the lower part of the piston is designed according to guide hole with a steel bush, forming a dual direction guide and making sure the valve moves freely and stably even if it is a much more aperture, thus improving the duration, safety an reliability. (Refers to seeks c)