Learn some safety knowledge about valves from a large accident

Learn some safety knowledge about valves from a large accident

In all kinds of pipe network systems, valves are called “throat”. Leakage, shutdown, and major accidents caused by valve performance and quality problems have brought immeasurable losses to the normal operation of industrial production, personal safety, and property (such as the Three Mile Island nuclear power plant accident in the United States that shocked the world). According to relevant statistics, the major production accidents caused by the world every year, 1/3 of which are caused by valve quality accidents.

In August 2020, the thermal power project of Madian Gangue Power Generation Company in China was undergoing thermal commissioning when a high-pressure steam pipeline suddenly broke, resulting in a major safety accident that killed 21 people and injured 5 people (3 of whom were seriously injured).

It is reported that the valve used by the factory is not a qualified high-quality dn25-dn3600 butterfly valve, and the cause of the accident includes improper operation as well, which shows that not only to select a good butterfly valve, but also to pay attention to the operation of the butterfly valve.

The cause of the terrible accident

After preliminary investigation and analysis, the main causes of the accident are: the weld seam of the main pipeline flowmeter valve at the steam outlet of the No. 2 boiler was cracked, and a large number of high temperature and high pressure steam spilled out, resulting in the breakage of the glass of the main control room, causing serious casualties in the main control room.

Causes of valve weld failure:

non rising stem gate valve DN100

  1. There are problems with the material of the pipeline, and the possibility is that the material of the main steam pipe is unqualified.
  2. The welding quality is not up to standard, the weld treatment process is not perfect, and 100% welding seam detection is not carried out after welding.
  3. The layout of the pipeline is unreasonable, and the accident pipeline is arranged in the 8m floor, which is the connection of the main steam pipe and the outlet pipe of No. 2 furnace in the factory, and also the boiler water supply platform. A large number of pipelines are cross-arranged and the space is limited, which leads to the expansion of the pipeline is blocked and the welding joint is easily broken due to thermal stress.
  4. There is a phenomenon of overtemperature and overpressure in operation.When using a gate valve,such as a bs5163 gate valve pn16,the control of temperature and pressure needs a lot attention.BS5163 is a British Standard specification for resilient-seated gate valves used for waterworks purposes. PN16 is a pressure rating that indicates the valve is designed to withstand a maximum pressure of 16 bar (232 psi) at a temperature range of -10°C to +80°

Precautions of applying valves

We have to learn from every single valve accident to avoid further accident from happening to the highest level.Here are some tips on the application of gate valves,including ggg50 butterfly valve,from TWT,one of the largest valve manufacturer:

1.The valve storage environment should pay attention to, should be stored in a dry and ventilated room, and blocked at both ends of the path.

2.The valve should be checked regularly, and remove the dirt on it, and apply anti-rust oil on its surface.

3.After the installation of the application of the valve, it should be regularly repaired to ensure that it works normally.

4.Check whether the sealing surface of the valve is worn, and repair or replace it according to the situation.

5.Check the trapezoidal thread wear of the valve stem and valve stem nut, whether the packing is outdated and invalid, and carry out the necessary replacement.

GGG50 Butterfly Valves: A Comprehensive Guide to DN25-DN3600 Sizes and Offset Design

GGG50 Butterfly Valves: A Comprehensive Guide to DN25-DN3600 Sizes and Offset Design

In the complex landscape of industrial fluid control, selecting the right valve is paramount to ensuring optimal performance, efficiency, and longevity. Among the array of valves available, the GGG50 butterfly valve emerges as a versatile and robust solution.

This blog post explores the key features and advantages of GGG50 butterfly valves, with a focus on their extensive size range (DN25-DN3600) and the innovative offset design that sets them apart in fluid control applications.

Key Features of GGG50 Butterfly Valves

Clamp Butterfly Valve 2

Ductile Iron Construction (GGG50): The use of GGG50 ductile iron in the construction of butterfly valves provides exceptional mechanical properties. With high tensile strength and ductility, GGG50 ensures the valve’s ability to withstand the rigors of industrial operations, including high-pressure and high-temperature conditions.

DN25-DN3600 Size Range: One of the standout features of GGG50 butterfly valves is their extensive size range, spanning from DN25 to DN3600. This broad sizing capability makes them suitable for a wide variety of applications, from small-scale processes to large industrial operations requiring substantial flow control. So sometimes, we also call GGG50 series as dn25-dn3600 butterfly valve.

Offset Design: GGG50 butterfly valves often feature an offset design, a key innovation that distinguishes them from other valve types. The offset butterfly valve reduces wear and tear on the valve components, leading to increased longevity and lower maintenance requirements compared to other valve configurations.

Bi-Directional Sealing: GGG50 butterfly valves are designed to provide bi-directional sealing, ensuring a tight shut-off in both directions of flow. This feature enhances their versatility, making them suitable for applications where fluid flow direction may vary.

Butterfly Valves Applications Especially For GGG50

Water and Wastewater Treatment Plants: In water and wastewater treatment facilities, GGG50 butterfly valves play a crucial role in regulating the flow of liquids through different stages of the treatment process.

Chemical Processing: GGG50 butterfly valves find application in the chemical industry, where they are used to control the flow of various chemicals. The corrosion-resistant nature of ductile iron ensures that the valves can withstand the corrosive properties of many chemicals.

Power Generation: In power plants, where the control of water, steam, and other fluids is essential, GGG50 butterfly valves provide reliable and efficient flow control.

Oil and Gas Industry: GGG50 butterfly valves are employed in the oil and gas industry for the control of various fluids, including crude oil and natural gas.