Basic Introduction to Water-Tight Gate Valves and Installation Precautions

A water-seal gate valve is a type of shutoff device used for full opening and closing. The core structural features of the water-seal gate valve include the water-tight design of its stuffing box and the bidirectional elastic sealing of the double gate plates. The valve cover stuffing box of the water-seal gate valve features a water-tight structure.

When water at a pressure of 0.6 to 1.6 MPa is introduced into the interface, it isolates the system from the atmosphere, ensuring the system has excellent airtightness. Additionally, the water-sealed gate valve features double gate plate bidirectional elastic sealing, which operates flexibly and quickly with reliable sealing.

The specific structural features of the water-seal gate valve are as follows:

The water-tight structure: The stuffing box is designed as a water-tight structure, incorporating 0.6～1.6MPa water-filled packing, featuring low friction and excellent sealing performance, ensuring the airtightness of the system.

2. Dual Gate Plate Bidirectional Elastic Sealing: Equipped with dual gate plate bidirectional elastic sealing, it offers easy operation, reliable sealing, and excellent performance.

3. Valve Stem Treatment: The valve stem undergoes hardening and surface nitriding, offering excellent corrosion resistance, abrasion resistance, and wear resistance.

4. Connection Methods: Valve connections are available in two types—flanged and welded, with operation methods being manual and electric.

The Application Scope of Water-Tight Gate Valves:       

Pipe valves for oil and non-corrosive gas lines, particularly suitable for the steam turbine vacuum condensing system in power plants; Water-seal gate valves: Pressure rating is PN16~PN160, steel gate valves with 150LB-900LB pressure class are suitable for pressures of 1.6~25MPa/2.0-15.0MPa.

Pipe systems suitable for various industrial conditions in the oil, chemical, and power industries, with operating temperatures ranging from -29 to +550°C, are applicable to media such as water, oil products, steam, and acidic mediums.Materials typically include: cast steel WCB, stainless steel CF8(M), CF3(M), forged steel A105, F304(L), F316L, etc.

Installation precautions for water-seal gate valves include the following points:

Pre-installation Preparation: Prior to installing the water-sealed gate valve, comprehensive preparation is required, including verifying the accuracy and completeness of the construction drawings and related technical documents; preparing the necessary installation tools and materials, such as wrenches, screwdrivers, bolts, washers, nuts, etc.

Develop a detailed installation plan, including construction steps and time milestones; inspect the model and specifications of the gate valves to ensure they meet design requirements, and check for any damage to the valve disc and seat; prepare necessary protective gear, such as hard hats and gloves.

2. Installation Location Selection: Choosing the right installation location is crucial for ensuring the normal operation and maintenance of the gate valve. Consider ease of pipeline connection, accessibility for maintenance and inspection; avoid vibration and impact to prevent affecting the valve's lifespan and performance.

To prevent valve material aging and damage, avoid exposure to sunlight or harsh environments.

3. Installation Direction Confirmation: When installing gate valves, ensure that the valve's centerline aligns with the pipeline's centerline, and use a level to check if the valve is horizontal. For large-sized gate valves and pneumatic control valves, they should be installed vertically to prevent the valve core from being excessively heavy and tilting to one side, which could lead to leakage.

4. Installation Procedures: The installation operation is a critical step in the entire installation process. It involves mounting the gate valve onto the pipeline and securing the flanges with bolts; adjusting the valve position to ensure smooth operation and no jamming; and conducting a seal check to ensure a firm installation with no leakage.

During installation, be mindful of the valve's operation methods and flow adjustment techniques to ensure proper usage and maintenance.

5. Pilot Run and Quality Control: After installation is completed, conduct a pilot run to check the opening and closing of the valves and for any leakage in the pipeline system. Throughout the installation process, strict quality control is required to ensure that the installation of the gate valves meets the standard requirements.

Prevent equipment malfunctions or safety accidents due to improper construction.

6. Safety Precautions: During the installation process, please observe the following safety measures: Wear protective gear such as gloves and safety goggles; when dismantling or replacing valve components, turn off the power or gas source first to prevent any accidents; during installation,

It is crucial to prevent valves from being impacted or damaged by external forces to avoid affecting their lifespan and performance.