I. Background of Port Machinery Corrosion Protection

Port machinery is the core equipment in port operations. The long-term and stable operation of port machinery is the basic guarantee for normal port operation. The main operating environment of port machinery is in the open-air environment of the docks, where the humidity is extremely high, which can also cause corrosion to port machinery. Therefore, during the production process of port machinery, the corrosion protection issues of port machinery must be fully considered to improve the production technology and maintenance level of port machinery, ultimately enhancing the competitiveness of the port.

In the actual operation of port machinery, it is easily corroded by seawater. Considering the harsh external environment of port machinery, the high air humidity will also cause a certain degree of corrosion on the surface of the machinery.

Therefore, it is essential to carry out corrosion protection treatment that fully meets the technical standards during the production process of port machinery. Even after the operation of port machinery, different degrees of corrosion may still occur. This can even lead to cracks and peeling on the surface of port machinery, causing the corrosion protection coating to lose its original protective function.

I. Reference Standards

Current national standards, relevant regulations, and mandatory standard provisions;

"Code for Construction and Acceptance of Building Anti-corrosion Engineering" (GB50212-2002)

"Standard for Corrosion and Rust Removal Levels of Steel Surface Before Coating" (GB8923-1988)

"Safety Regulations for Coating Operations and Safety Management Rules" (GB6514-1995)

"Quality Requirements for Anti-corrosion Coatings" (GB6514-1991)

"Safety Regulations for Coating Operations, Paint Process Safety, and Ventilation Purification" (DJ/T6931-1999)

"Code for Construction and Acceptance of Industrial Equipment and Pipeline Anti-corrosion Engineering" (HGJ229-91)

"Safety Regulations for Coating Operations and Safety of Surface Preparation Process" (GB7692-87)

"Noise Limits at Construction Sites" (GB12523-90)

ISO9001 Quality Management System Documents

ISO14001 Environmental Management System Documents

GB/T28001 Occupational Health and Safety Management System Documents

I. Design Basis

Environmental Conditions: The corrosion level of atmospheric environments on steel structures can be determined according to Table 1.

I. Anti-Corrosion Solutions for Newly Built Port Machinery

Components: Shore cranes, yard cranes, rail-mounted gantry cranes, ship loaders, screw unloaders, bucket wheel excavators, gantry cranes, jib cranes, floating cranes, fixed cranes, conveyor belts, etc.;

Environment: These port machinery equipment are installed and operated in ports, where the atmospheric corrosion environment is harsh, with some parts even in splash zones;

Dreamneng anti-corrosion experts believe that the special engineering, overload operations leading to metal fatigue, and impacts from heavy cargo on port machinery equipment damage the anti-corrosion materials on the metal structure surfaces, accelerating the formation and spread of corrosion. Therefore, proper anti-corrosion coating is crucial for ensuring the long-term safe and effective operation of port machinery equipment.

Table 1: Anti-Corrosion Solution for External Surface of Port Machinery Equipment (New Construction)

Table 2: Anti-Corrosion Solution for Enclosed Internal Surface of Port Machinery Equipment

II. Port Machinery Refurbishment and Maintenance Anti-Corrosion Solutions

The marine environment has a significant impact on the atmospheric corrosion of the steel structures of port machinery, including chemical and biological factors that usually interact with each other. Dreamneng Technology will focus on the differences between these two factors to assist our customers in their future anti-corrosion coating work.

For the effective service life of protective coatings on the steel structures of newly built large port machinery and equipment, the international standard typically requires a minimum of 15 years. However, this depends on the quality of the anti-corrosion coating construction and necessary maintenance during the operational life of the equipment. Therefore, modern port machinery coatings emphasize proper surface preparation before coating, using high-quality anti-corrosion coatings, correctly designing the coating system, strict on-site construction management, and ongoing maintenance to ensure the coating's service life.

Table 3: Port Machinery Equipment Refurbishment Anti-Corrosion Solution

I. Concrete Surface Cleaning for Land Bridges and Wave-Proof Structures

Concrete structures requiring coating protection can be divided into two main categories. The first category is newly poured concrete, which generally needs curing for at least 28 days under standard conditions (subject to variations in environmental temperature and humidity). It is characterized by a high water content and strong surface alkalinity. The second category is surfaces that have been in use for some time and have suffered varying degrees of corrosion or weathering. These surfaces are characterized by high roughness, porosity, and a weak interface layer with low strength, and may also have contamination such as oil stains and inorganic salts. The surface of the substrate to be coated must undergo "surface treatment" and "cleaning." Surface cleaning is essential for ensuring proper coating application and adhesion. "Cleaning" aims to remove dust, oils, moisture, and weak interface layers to increase the inter-layer adhesion between the substrate and the coating.

Table 1: Coating Protection Solutions for Concrete Land Bridges and Wave-Proof Structures

I. New Tank Construction Project

Tanks are one of the essential pieces of equipment for storing liquid raw materials and intermediate products at port enterprises, and are indispensable in the crude oil pipeline transportation industry. The current specifications for crude oil tanks include volumes such as 10,000 cubic meters, 20,000 cubic meters, 50,000 cubic meters, and 100,000 cubic meters. According to their structure, they can be divided into dome-roof tanks and floating-roof tanks. In recent years, during major repairs of oil tanks, it has been found that corrosion is quite severe, particularly on the tank bottom plate, with corrosion pits reaching depths of 4-5mm. The distribution rate of corrosion pits reaches 20-25 pits/m2, and there are also localized perforations. The corrosion of the floating roof plates is even more severe, with the thickness of the single roof plate reduced by 50%-60%, and some perforations as large as 300×200 mm2. According to related survey data, in oil tank corrosion, the corrosion of the single roof plate accounts for 60%, while the bottom plate corrosion accounts for 40%. In cases where corrosion perforations lead to oil leaks and tank shutdowns, perforations in the bottom plate account for 76.4%, while perforations in the floating roof plate account for 23.6%. Therefore, strengthening tank protection and selecting appropriate anti-corrosion measures are crucial for increasing the tank's service life and reducing the occurrence of accidents.

Table 1: Anti-Corrosion Scheme for Fire Water Tank Inner Wall

The fire water tank may experience a decrease in structural strength, wall defects causing leaks, and even environmental pollution and safety risks due to corrosion. When applying anti-corrosion coatings, it is important to identify and focus on treating the tank's inner wall, particularly the weld seams at the bottom and areas prone to liquid level fluctuations. During construction, strict quality control of the coating is required, including the complete removal of old coatings and rust layers to ensure an even and thorough application. Preventing moisture from entering the bottom plate and foundation gaps of the tank can slow down corrosion. The sacrificial anode quantity should be designed accurately to meet the tank's maintenance cycle requirements. The fire water spray system should be adjusted to prevent water from contacting the insulation outer layer and the tank wall. Strengthen the surface welding method by changing from spot welding to full welding to block the pathway for moisture to enter the insulation layer. Regular inspections of tank corrosion should be carried out using macro inspection and ultrasonic thickness testing methods. Suitable anti-corrosion materials should be selected based on factors such as medium, temperature, and pressure. The coating thickness and uniformity should be controlled using specialized equipment and trained personnel. A quality control system should be established. After construction, use coating thickness measurement tools to regularly check the quality of the anti-corrosion layer and ensure the tank operates safely and stably in the long term.

Table 2: Anti-Corrosion Scheme for Sewage Tank Inner Wall

Table 3: Corrosion Protection Scheme for the Inner Wall of Crude Oil Storage Tank

Table 4: Corrosion Protection Scheme for the Inner Wall of Edible Oil Storage Tank

Table 5: Corrosion Protection Scheme for the Outer Wall of Storage Tank

II. Tank Exterior Wall Refurbishment

When refurbishing the anti-corrosion paint of a tank, key points include surface pre-treatment, environmental control, coating system selection, uniform application, thickness control, safety protection, finished product protection, quality inspection, and regular maintenance. First, thoroughly clean and remove rust from the tank surface to ensure coating adhesion. The construction environment must meet temperature and humidity requirements to avoid adverse weather conditions. Select an appropriate anti-corrosion coating system and use high-pressure airless spraying to ensure even coating. Control the coating thickness to meet the design requirements. Workers must wear protective gear to ensure safety. After construction, protect the coating to prevent damage. After completion, conduct quality inspection and regularly check and maintain the coating to ensure its anti-corrosion effectiveness.

Table 6: Tank Exterior Wall Maintenance and Refurbishment Anti-Corrosion Plan

Corrosion Protection Plan for Steel Pipe Piles of Port Wharf

Steel pipe piles are generally used as the foundation for offshore structures such as bridges, ports, and offshore platforms. These structures are exposed to very severe corrosive environments. Due to the harsh marine corrosion environment, steel pipe piles often face significant corrosion risks. As people increasingly recognize the severity of corrosion and deepen the concept of sustainable development, significant progress has been made. Ports often use steel sheet piles or steel pipe piles as the structure, and the harsh seawater environment causes severe corrosion on steel piles. Improper material selection, poor design, and the lack of protective measures often lead to the need for early maintenance, reinforcement, or even decommissioning of the wharf.

Table 1: Corrosion Protection Plan for Steel Pipe Piles at the Wharf