Treatment of The Stuck State of The Electric Stop Valve J961Y-200 at 400℃ Temperature

In industrial production, the stop valve is a key device for controlling fluid media, especially in high temperature and high pressure environments, where its stability and reliability directly affect the system operation efficiency. As a typical representative of welded design, the J961Y-200 high temperature and high pressure electric stop valve is widely used in chemical industry, energy and other fields due to its strong sealing performance and compact structure. However, when the valve is stuck under 400℃ working conditions, it will not only cause process interruption, but also may cause safety hazards. Below we will analyze the causes of stuck and countermeasures to provide reference for technicians.

I. The impact of high temperature and high pressure environment on stop valve

The high temperature condition of 400℃ places strict requirements on the performance of the stop valve J961Y-200. First, the material is prone to deformation under long-term thermal stress. The difference in thermal expansion coefficient between the valve body and the valve stem may cause abnormal matching clearance, which in turn causes jamming. Secondly, the sealing surface is easily worn due to oxidation or medium corrosion at high temperature, resulting in inability to fully fit in the closed state, forming local stress concentration. In addition, the lubrication system of the electric drive device is prone to failure in a high temperature environment. The carbonization or loss of grease will increase the friction resistance of the transmission parts and eventually cause jamming.

The J961Y-200 stop valve adopts a welded connection. Although the risk of flange leakage is eliminated, the problem of thermal stress accumulation in the welded joint cannot be ignored. If the welding quality is poor, microcracks may expand at high temperatures, aggravate the deformation of the valve body, and further affect the valve action. Therefore, the jamming phenomenon is often the result of the combined effect of material properties, structural design and operating environment, and requires comprehensive judgment and targeted treatment.

II. Emergency treatment of jamming phenomenon

When the J961Y-200 stop valve is jammed under 400℃ working conditions, the operator should prioritize safety and take the following steps to restore the function:

First, cut off the power supply immediately to prevent the motor from being damaged by overload. Then try to slowly rotate the valve stem with the handwheel to gradually release the stress of the jammed part. If manual operation is ineffective, it is necessary to check whether there is foreign matter blocking or sealing surface adhesion. For example, if the medium contains particulate impurities, it may accumulate in the valve cavity and cause the valve disc to jam. At this time, it needs to be disassembled and cleaned.

The state of the lubrication system is one of the key factors. High temperature may cause carbonization or loss of grease, so it is necessary to check the lubrication of the valve stem thread, stuffing box and other parts. If insufficient lubrication is found, high-temperature resistant silicone-based grease can be injected, but it must be ensured that the lubricant is compatible with the medium to avoid secondary contamination or corrosion.

Wear or adhesion of the sealing surface is also a common cause. At this time, the valve cover needs to be removed to observe whether the contact surface between the valve disc and the valve seat forms hard deposits due to high-temperature oxidation. If there is such a problem, it is necessary to use a grinding sheet or polishing tool to repair the sealing surface to ensure its flatness. If the valve body is stuck due to thermal stress deformation, local heating or cooling can be used to alleviate the deformation, such as uniformly heating the deformed part to the material tempering temperature and then slowly cooling it, or using hydraulic correction equipment to adjust the shape.

For stuck caused by valve stem bending, packing aging or sealing ring failure, key components need to be replaced in time. For example, high-temperature resistant alloy valve stems, high-performance graphite packing or fluororubber sealing rings are selected to improve the adaptability of the equipment under extreme working conditions.

III. Long-term maintenance and prevention strategies

To reduce the risk of the J961Y-200 stop valve getting stuck at 400℃, it is necessary to start from the three aspects of design selection, daily maintenance and operating specifications:

1. Material and structural optimization

The valve body and valve stem should preferably use high-temperature resistant alloy steels such as ASTM A182 F310/F310H, whose creep resistance and oxidation resistance can effectively cope with high temperature challenges. The design of the welded joint must comply with the ASME standard to ensure the quality of the weld. The sealing structure can adopt a wedge design or a self-cleaning solution to reduce the erosion of the sealing surface by medium particles.

2. Regular maintenance and inspection

It is recommended to refill the lubrication system, clean the sealing surface and debug the drive mechanism of the valve every quarter. Use ultrasonic flaw detection or X-ray detection technology to evaluate the integrity of the valve body and welded joints to detect microcracks or deformation in time. Under high-risk conditions, the inspection cycle can be shortened to once a month, and a maintenance file should be established to record the equipment status.

3. Operational specifications and training

Operators need to master the correct opening and closing skills to avoid frequent movements that cause wear on the sealing surface. The training content should include manual operation methods when the electric drive fails, as well as emergency handling procedures in the event of a jam. Develop a standardized operation manual, clarify the division of responsibilities, and ensure rapid response in emergencies.

4. Environmental control and auxiliary measures

Reduce the temperature of the valve body through a water-cooled jacket or air-cooled device to alleviate the impact of thermal stress. In scenarios where the medium is prone to scaling or contains particles, installing a filter upstream can reduce the damage of impurities to the sealing surface. At the same time, monitor the pressure fluctuations of the pipeline system to avoid damage to the valve caused by abnormal impact.

In complex and changing industrial environments, the reliability of the stop valve J961Y-200 has always been the core consideration of engineering design. By continuously improving technology and management methods, we can provide more efficient and safe solutions for fluid control in high temperature and high-pressure scenarios.

When looking for high-quality, reliable stop valves, YOYIK is undoubtedly a choice worth considering. The company specializes in providing a variety of power equipment including steam turbine accessories, and has won wide acclaim for its high-quality products and services. For more information or inquiries, please contact the customer service below:
E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229

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