1、Brief introduction

Parallel double gate valve, also known as open type flat gate valve or expansion gate valve, is a high-performance flat gate valve with bi-directional cut-off forced sealing, which is a gate valve design product introduced from abroad. The gate of this valve is a pair of two inclined gate plates that match the letter K, and when the valve is opened, the two gate plates retract along the inclined surface, causing the sealing pair to detach from contact. The sealing surface of the valve has no friction, making the valve operate very easily and reducing the driving torque of the valve; When the valve is closed, the two gate plates expand along the inclined surface, causing the inlet and outlet of the valve to achieve bi-directional forced sealing. The gate and seat of the valve have undergone special surface treatment, with good wear resistance and corrosion resistance, and can be widely used in geothermal media, natural gas, oil extraction, gathering, transportation, and storage facilities; It can also be widely used as equipment for downstream petrochemical process pipelines, cutting off various corrosive or toxic media such as oil, gas, acid, alkali, and high-temperature media. After years of research and development, our company has develop

ed a non diversion hole expansion flat gate valve, which has a patented project.

2、Design standards

API 6D "Pipeline and Pipeline Valve Specification"

ASMEB16.5-2009 "Pipe Flanges and Flanged Fittings"

ASMEB16.34-2009 "Valves Flanged, threaded, and welded ends

ASMEB16.5-2009 "Pipe Flanges and Flanged Fittings"

API 598-2016 "Inspection and Testing of Valves"

API 600-2015 "Steel Flanges and Butt Welded Gate Valves"

ASME B16.10 "Structural Length of Metal Valves"

GB/T13927-2016 "Pressure Test for Industrial Valves"

GB/T12221-2005 "Structural Length of Metal Valves"

GB/T19672-2021 "Technical Conditions for Pipeline Valves"

HG/T20592~20635-2009 "Steel Pipe Flanges, Gaskets, and Fasteners"

JB/T5298-2016 "Steel Flat Gate Valves for Pipelines"

3、Structural characteristics of expansion type double gate flat gate valve

1. The transmission device drives the valve stem, which in turn drives the main gate to move up and down; The auxiliary gate moves together with the main gate under the drive of the connecting rod, thereby achieving the opening and closing positions of the combined gate and opening the gate plate to achieve the flow and cutoff of the upper and lower media.

2. At the beginning and end of the movement process of the combination gate, due to the change in the position of the inclined plane of the main and auxiliary gate, the sealing surfaces on both sides of the combination gate produce a tight and expanding effect, in order to achieve forced sealing and protect the sealing surfaces when opening.

3. When fully open, a pair of inclined surfaces on the combination gate are separated, and the sealing surfaces of the valve body are tightly pressed on both sides of the gate to isolate the medium and other impurities from entering the valve chamber.

4. During the opening and closing process, the two inclined surfaces of the main and auxiliary gate plates are closely adjacent to both sides of the gate plate, with a small gap between them and the sealing surface of the valve body, ensuring that the gate plate can move freely.

5. When fully closed, a pair of inclined surfaces under the combination gate are separated, and the two sides of the gate are pressed tightly against the cover to achieve absolute sealing of the valve.

6. Due to the fully bi-directional sealing characteristics, when the pressure inside the valve chamber increases due to temperature changes or other reasons, this pressure cannot be released by the pipeline sealing surface, but is released through the safety device on the valve body, thereby ensuring the safe operation of the pipeline and equipment.

7. When the valve is in the fully open or fully closed state, the valve chamber and the medium are completely isolated. Therefore, in emergency situations, the vent valve and drain valve can be opened first to release pressure, and then emergency treatment can be carried out.

8. Full bore design for easy online cleaning, smooth channel when fully open, minimal flow resistance coefficient, and no pressure loss.

9. The installation orientation of valves is flexible, and can be installed vertically, horizontally, in reverse, tilted, etc.

10. The sealing design on the valve stem allows the valve stem packing to be replaced under full working pressure.

4、 Main external dimensions and connection dimensions

Exterior dimensions of 16C/25C/150LB

PN40C/300LB external dimensions

Precautions for using parallel double gate valve:

1. Say the important thing three times: don't push yourself to the brink of death! Don't push yourself to the brink of death! Don't push yourself to the brink of death!

2. When opening or closing in place, the valve stem handle or handwheel should be rotated 1/2 turn. To ensure that the gate is in a floating state and maintain good sealing performance.

Note: Pre understand the detailed parameters, data, and prices of parallel double gate gate valves,

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