【Haichuan Chemical Valve Management】Series of Posts – Damage to valves during transportation and handling is often not due to quality issues, but rather problems that occur during transit

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Proper management of valves is the foundation for stable operation. Everyone is welcome to engage in discussions and share insights on this series of posts: 【HaiChuan Chemical Valve Management】 series of posts: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5719309 ---------------------------------------------------------------- Disclaimer: The content contained in this article is intended solely for technical exchange and reference purposes only; it does not constitute any form of professional engineering advice, design basis, or operational guidance. ----------------------------------------------------------------------------------- Valves get damaged during transportation and handling; in many cases, it’s not a quality issue but rather a problem related to the shipping process. Have you ever encountered this situation: a newly purchased valve that appears to be properly packaged, but upon opening it, the handwheel is misaligned, there’s a dent on the flange sealing surface, or the valve stem is bent? Many people’s first reaction is, “The quality of this valve is poor.” However, in reality, it’s often not the manufacturer’s fault; problems occur during transportation and handling. Valves, well, they can be considered sturdy, but they can also be fragile. The precision requirement for the flange sealing surface is on the order of micrometers; even a slight impact can cause damage to the sealing surface, which will definitely lead to leaks once it is installed. Grey cast iron valves are more brittle; they crack instantly when dropped on the ground. Statistics show that approximately 23% of valve failures worldwide are actually caused by vibrations, impacts, or environmental corrosion during transportation. This is a rather high percentage. Where are the parts of a valve most prone to problems during transportation? Broken handwheels, bent valve stems, broken supports, damaged flange sealing surfaces – especially in gray cast iron valves, most of these damages occur during transportation. The reason is simple as well: many porters don’t understand valves; they think it’s just a piece of metal, so they treat it carelessly, throwing or dropping it without any awareness of the complexities involved. The porter doesn’t know, but you need to know. There are several key points in valve transportation: when lifting, where should the ropes be attached? It must never be tied to the handwheel or valve stem! A handwheel is meant for turning, not for lifting. The rope should be tied to the flange or bracket, as these are the strongest parts of the valve. How should the valve be placed? During transportation, the valve should be placed upright or tilted, with the stem pointing upward. Why? Since the valve stem points upward, in case of any vibrations, it is not prone to bending. If it is placed lying flat, the bumps during transportation can easily bend the valve stem. For valves that are unstable when placed, they should be tied securely with ropes or fixed with blocks to prevent them from colliding with each other. What is the biggest fear when loading and unloading by hand? The worst fear is being “thrown away”. It is strictly prohibited to throw the valve off the vehicle, or from the ground onto the vehicle. When the valve hits the ground, the impact force is sufficient to create dents in the flange sealing surface. Handle with care during transportation; stacking is strictly prohibited. What should the valve be in before transportation? Different types of valves are in different states during transportation. Gate valves and stop valves should be in the closed position to prevent the closing elements from vibrating during transportation. Ball valves and plug valves should be in the open position to minimize the exposure of the sealing surfaces. Butterfly valves are usually shipped in a closed or slightly open position. The transmission mechanism should be packaged and transported separately from the valve. What are the tricks behind packaging before leaving the factory? Reputable manufacturers pay attention to the packaging. Small valves are packed in corrugated cartons with cushioning material, while large valves use wooden crates with shock-absorbing frames; for sea transportation, vacuum moisture-proof films are also required. The outside of the packaging box will indicate the orientation for placement, the maximum number of items that can be stacked, and the storage conditions required. When you receive the goods, don’t rush to open them; first check if the packaging is damaged. How should it be stored once it arrives at the warehouse? After the valves are stored, the water and dust accumulated during transportation should be wiped away promptly. The machined surfaces, valve stems, and sealing surfaces that are prone to rusting should be coated with an anti-rust agent or covered with anti-rust paper. The import and export passages should be sealed with plastic covers or wax paper to prevent dirt from getting in. When storing, the small valves are arranged on the shelves according to their model specifications, while the large valves are placed on the ground; however, they must be kept upright or at an angle, with the flange sealing surfaces not in contact with the ground, and they must not be stacked on top of each other. Some experienced workers, in an effort to save time, stack the valves on top of each other, which damages the sealing surfaces of the valves at the bottom; this is a fairly common occurrence. What should be noted for long-term storage? Starting from the date of manufacture, the valve should be subjected to a pressure test again after 18 months. Why? Because rust inhibitors have a shelf life, they become ineffective over time. Rust inhibitors and lubricants that have exceeded their specified usage period should be replaced or replenished regularly. There is another detail that many people are not aware of: if the valve uses asbestos packing, it should be removed from the packing box if it is not used for a long time. Because electrochemical corrosion occurs between asbestos and metals, the valve stem will be corroded and damaged over time. What should be done with valves that are not installed at the construction site for now? Don’t open the packaging! Just place it in the packaging box, put it in a safe place, and protect it from rain and dust. Removing the packaging is like taking off the valve’s \"protective coat\"; the working environment is dirty and chaotic, with dust and mud getting inside, causing the valve to be \"injured\" even before it is used.