Valves are the most common equipment in chemical enterprises. Installing valves may seem easy, but if not carried out according to relevant technical standards, it can lead to safety accidents. Today, we would like to share some experience and knowledge about valve installation with you.

I. Conduct a water pressure test during winter construction at negative temperatures.

• Consequence: Due to the rapid freezing inside the pipe during the hydrostatic test, the pipe is damaged by freezing.
• Measures: Try to conduct a water pressure test before winter construction, and blow out the water after the test, especially the water inside the valve must be completely removed, otherwise the valve may rust or even freeze and crack. When conducting a water pressure test in winter, the project must be carried out at a positive temperature indoors, and the water must be blown out after the test.

II. The pipeline system is not washed carefully before completion, and the flow and speed cannot meet the requirements of pipeline flushing.

• Consequences: Water quality cannot meet the operational requirements of the pipeline system, often resulting in reduced pipeline cross-sections or blockages.
• Measures: flushing should be carried out with the maximum design flow rate in the system or a water flow rate of not less than 3m/s. It should be considered as qualified if the water color and transparency at the outlet are visually consistent with those at the inlet.

III. Sewage, rainwater, and condenser pipes are concealed without undergoing a closed water test.

• Consequences: It may cause water leakage and cause losses to users.
• Measures: The closed water test work should be strictly inspected and accepted according to the specifications. The concealed installation of sewage, rainwater, condenser pipes, etc. in underground burial, ceiling, and between pipes should ensure no leakage.

IV During the hydraulic pressure strength test and tightness test of the pipeline system, the leakage inspection is not sufficient.

• Consequence: Leakage occurs after the pipeline system is running, affecting normal use.
• Measures: When testing the pipeline system according to design requirements and construction specifications, in addition to recording pressure values or water level changes within the specified time, it is particularly important to carefully check for leakage problems.

V. The flange plate of the butterfly valve is made of ordinary valve flange plate.

• Consequences: The dimensions of the flange plates for butterfly valves and ordinary valves are different. Some flanges have a small inner diameter, while the butterfly valve's disc is large, causing it to be unable to open or to open forcibly, resulting in damage to the valve.
• Measures: The flange plate should be processed according to the actual size of the butterfly valve flange.

VI. The valve installation method is incorrect.

For example, the water (steam) flow direction of the stop valve or check valve is opposite to the mark, the valve stem is installed downward, the horizontally installed check valve is installed vertically, the handle of the open-stem gate valve or butterfly valve has no space for opening and closing, and the valve stem of the concealed valve does not face the inspection door.

• Consequences: Valve malfunction, difficulty in switch maintenance, and often water leakage caused by the valve stem pointing downwards.
• Measures: Install the valve strictly according to the installation instructions. For the rising stem gate valve, leave enough space for the valve stem to extend and open. For the butterfly valve, fully consider the space for rotating the handle. The valve stem should not be lower than the horizontal position, and it should not be downward. For concealed valves, not only should there be an inspection door that meets the needs of opening and closing the valve, but also the valve stem should face the inspection door.

VII. The specifications and models of the installed valves do not meet the design requirements.

For example, the nominal pressure of the valve is less than the system test pressure; gate valves are used for water supply branch pipes with diameters less than or equal to 50mm; stop valves are used for hot water heating dry and vertical pipes; and butterfly valves are used for fire pump suction pipes.

• Consequences: It affects the normal opening and closing of the valve and the adjustment of resistance and pressure. It may even cause damage to the valve during system operation and necessitate repairs.
• Measures: Familiarize yourself with the application scope of various valves, and select the specifications and models of valves according to the design requirements. The nominal pressure of the valve should meet the requirements of the system test pressure. According to the construction specifications, when the diameter of the water supply branch pipe is less than or equal to 50mm, a globe valve should be used; when the diameter is greater than 50mm, a gate valve should be used. The hot water heating dry and riser pipes should use gate valves, and the suction pipe of the fire pump should not use butterfly valves.

VIII. The necessary quality inspection is not conducted according to the regulations before the installation of the valve.

• Consequences: The valve switch is not flexible during system operation, resulting in poor closure and leakage (steam) phenomena, causing rework and repair, and even affecting normal water (steam) supply.
• Measures: Before the installation of valves, pressure strength and tightness tests should be conducted. The tests should be conducted on 10% of each batch (of the same brand, same specification, and same model) and no less than one. For closed-circuit valves installed on the main pipe to cut off, strength and tightness tests should be conducted one by one. The pressure for valve strength and tightness tests should comply with the provisions of the Code for Acceptance of Construction Quality of Water Supply Drainage and Heating Works (GB 50242-2002).

IX. Improper installation of valves in high temperature environment.

• Consequence: leakage accident
• Measures: For high temperature valves over 200℃, they are at normal temperature during installation, but after normal use, the temperature rises, the bolts expand due to heating, and the gap increases, so they must be tightened again, which is called "hot tightening". Operators should pay attention to this work, otherwise leakage is likely to occur.

X. Valve flip-chip

• Consequences: Valves such as stop valves, throttle valves, pressure reducing valves, and check valves all have directionality. If installed upside down, the throttle valve will affect the effectiveness and lifespan of the valve; the pressure reducing valve will not work at all, and the check valve may even pose a danger.
• Measures: General valves have directional signs on the valve body; if not, they should be correctly identified based on the working principle of the valve. The valve cavity of the globe valve is asymmetric left and right, and the fluid should be allowed to pass through the valve port from bottom to top, which reduces fluid resistance (determined by shape) and saves effort when opening (due to the upward pressure of the medium). After closing, the medium does not press on the packing, which is convenient for maintenance. This is why the globe valve cannot be installed backwards. Gate valves should not be installed upside down (i.e., with the handwheel facing down), otherwise the medium will remain in the valve cover space for a long time, which can easily corrode the valve stem and is also prohibited for certain process requirements. At the same time, it is extremely inconvenient to replace the packing. For rising stem gate valves, do not install them underground, otherwise the exposed valve stem will be corroded due to moisture. For lift check valves, ensure that their valve discs are vertical during installation to facilitate flexible lifting. For swing check valves, ensure that their pin shafts are horizontal during installation to facilitate flexible swinging. Pressure reducing valves should be installed upright on horizontal pipelines, and should not be tilted in any direction.

In the valve industry, shut-off valves are widely used in various industrial piping systems due to their excellent regulation and sealing capabilities. However, a key aspect often overlooked during the installation of shut-off valves is their installation orientation. In reality, shut-off valves have specific directional requirements. Proper installation direction is not only crucial for the valve's sealing performance but also directly affects its service life and operational efficiency.

1. Directionality of Shut-Off Valves

The directionality of a shut-off valve is primarily reflected in the restriction of fluid flow direction. Typically, there is an arrow marking on the valve body indicating the direction of fluid flow. This directional marking is not optional but is designed based on the internal structure and working principle of the shut-off valve. Installing the valve according to this marking is a prerequisite for ensuring the proper operation of the valve.

2. Importance of Installing in the Correct Direction

(1) Ensuring Sealing Performance

One of the design intentions of a shut-off valve is to provide excellent sealing performance. The fluid should flow into the valve from below the seat and exit above the disc. When installed according to this direction, the fluid pressure will push the disc more tightly against the seat, forming a reliable seal. If installed in the reverse direction, the fluid may push away from the contact surface between the disc and the seat, leading to seal failure and potential leakage issues.

(2) Reducing Seat Erosion

When the fluid flows in the designed direction, the impact force on the valve seat is minimized, thereby reducing the risk of erosion and wear. If the fluid flows in the reverse direction, the strong impact force will directly act on the valve seat, potentially causing excessive wear and shortening the valve's service life.

(3) Reducing Operating Force

The closing action of a shut-off valve typically relies on assistance from fluid pressure. When installed in the correct direction, the fluid pressure helps in closing the valve disc, reducing the force required for operation. If installed in the reverse direction, operators will need to apply greater force to close the valve, which not only increases the difficulty of operation but may also accelerate mechanical wear of the valve.

In practical applications, it is essential to follow the fluid flow direction indicated by the arrow on the valve body during installation. This ensures that the shut-off valve's design advantages are fully utilized and guarantees the safety and stable operation of the system.

The Y-type globe valve is a valve with a unique structural design, widely used in various industrial fields. Its efficient fluid control capability and excellent sealing performance make it outstanding in complex and demanding working conditions.

 

Petroleum and Natural Gas Industry

1. Oil and Gas Transportation:

Y-type globe valves are widely used in petroleum and natural gas transmission pipelines. With their low-flow resistance design, they effectively reduce pressure loss, ensuring efficient long-distance transportation. Additionally, the excellent sealing performance of Y-type globe valves prevents leaks and ensures the safety of the transportation process.

2. Oil Production and Refining:

In oil production and refining processes, Y-type globe valves are used to control and regulate the flow of oil and gas. Their characteristics of high pressure resistance and corrosion resistance enable them to operate stably under harsh conditions, reducing the frequency of equipment maintenance and replacement.

 

Chemical industry

1. Corrosive Media:

In chemical production, various corrosive media such as acids, alkalis, and salts are commonly encountered. Y-type globe valves are manufactured using corrosion-resistant materials, enabling them to operate stably in such environments and protect pipeline systems from corrosion damage.

2. Process Control:

During chemical reactions, precise control of reactant flow and pressure is crucial. Y-type globe valves, with their high-precision regulating capability, ensure the stability and efficiency of the reaction process, thereby enhancing product quality and production efficiency.

 

Power industry

1. Steam Systems:

In electricity generation, control of steam systems is crucial. Y-type globe valves are used to regulate and shut off steam flow. Their high-temperature and high-pressure resistant materials allow them to operate stably in high-temperature and high-pressure environments, ensuring the safety and efficiency of power plants.

2. Cooling Water Systems:

In cooling water systems, Y-type globe valves are employed to regulate the flow of cooling water, ensuring the normal operation and cooling efficiency of power generation equipment. Their corrosion resistance and low maintenance characteristics make them highly favored in the power industry.

 

Water Treatment Industry

1. Sewage Treatment:

In sewage treatment plants, Y-type globe valves are used to control and shut off sewage flow. Their corrosion resistance and wear-resistant materials enable long-term operation in sewage environments containing various impurities and corrosive substances.

2. Drinking Water Treatment:

During drinking water treatment processes, Y-type globe valves are employed to regulate water flow and pressure, ensuring the stability and efficiency of water supply systems. Their low flow resistance design reduces energy consumption and enhances the operational efficiency of water treatment equipment.

 

Other application areas

1. Pharmaceutical Industry:

In pharmaceutical production, precise control of liquid and gas flow is essential. The high precision and reliability of Y-type globe valves make them crucial equipment in the pharmaceutical industry, ensuring the safety and quality of drug manufacturing processes.

2. Food and Beverage Industry:

In the food and beverage production process, there are stringent requirements for fluid hygiene and safety. Y-type globe valves, manufactured with food-grade materials, effectively control and regulate fluid flow, ensuring hygiene and safety in the production process.

 

The Y-type globe valve is widely used in various industrial pipeline systems and is favored for its unique design and reliable performance. It is typically used to shut off or regulate fluid flow.

 

1. Selection precautions

(1) Material Selection: Choose appropriate valve body and sealing materials based on the chemical properties, temperature, and pressure of the conveyed medium. Common materials include cast iron, stainless steel, and brass. For corrosive media, corrosion-resistant materials should be selected.

(2) Valve Specifications: Select the appropriate size of the Y-type globe valve according to the flow requirements and pressure demands of the pipeline system to ensure that the valve meets the system's process requirements.

(3) Structural Type: Determine whether a manually operated, electrically actuated, or pneumatically actuated Y-type globe valve is needed to suit different automation control requirements.

 

2. Installation precautions

(1) Installation Position: Ensure that the valve's directional markings align with the flow direction of the medium in the pipeline. The Y-type globe valve is typically installed in horizontal pipelines but can also be installed in vertical pipelines depending on the specific site requirements.

(2) Installation Space: When installing the Y-type globe valve, ensure there is sufficient space for operation and maintenance, allowing for easy opening, closing, and regular inspection and maintenance.

(3) Pipeline Cleaning: Before installation, thoroughly clean the pipeline system to remove impurities, welding slag, and other foreign objects to prevent them from entering the valve and affecting its sealing performance and operation.

(4) Secure Connections: During installation, properly secure the valve connections to the pipeline to avoid leaks caused by improper connections. Do not overtighten to prevent damage to the valve's sealing surfaces and connection components.

 

3. Operation precautions

(1) Opening and Closing Operation: When opening or closing the Y-type globe valve, slowly turn the handwheel or operate the actuator to avoid damaging internal components due to rapid or forceful operation.

(2) Opening and Closing Frequency: The Y-type globe valve has a limited number of opening and closing cycles. Frequent operation may lead to wear on the sealing surfaces, so control the frequency of operation according to working conditions.

(3) Open/Close Status Check: Regularly check the valve's open and close status to ensure it is fully opened or closed, avoiding a partially open or closed state that can affect system operation.

 

4. Maintenance precautions

(1) Regular Inspection: Periodically check all components of the Y-type globe valve, especially the sealing surfaces and valve stem, to ensure there is no wear, corrosion, or other abnormalities.

(2) Lubrication Maintenance: For manually operated Y-type globe valves, regularly lubricate the valve stem and threaded parts to reduce friction and ensure smooth operation. For electric or pneumatic actuators, regularly check the actuator's operating condition and lubrication.

(3) Seal Replacement: If the valve's sealing performance decreases, replace the seals promptly to ensure the valve's sealing effectiveness and longevity.

(4) Protective Measures: In environments prone to external impacts or vibrations, implement appropriate protective measures, such as installing supports or dampers, to protect the valve from damage.

 

5. Emergency response measures

(1) Leak Handling: If a leak is detected in the Y-type globe valve during use, immediately stop using the valve, close the upstream and downstream pipelines, and release the system pressure before performing repairs or replacement.

(2) Emergency Shutdown: In emergency situations requiring the rapid closure of the Y-type globe valve, avoid excessive force to prevent valve damage. It is recommended to operate the valve slowly and steadily.