Steel Wire Rope Maintenance of Portal Cranes at Zhoushan Changhong International Shipbuilding & Repair Co., Ltd.

Zhoushan Changhong International Shipyard Co., Ltd.. is a core enterprise in the shipbuilding and repair industry. As key heavy equipment in its production operations, portal cranes are widely used in the entire process such as cargo handling and shipbuilding & repair construction, distributed in multiple operation areas including wharves, dock areas and berths, and serve as an important support for the enterprise's production and operation.

As the core vulnerable part of portal cranes, the quality of lubrication and maintenance of steel wire ropes directly determines the operation safety, operation efficiency and service life of the equipment. Inadequate lubrication, corrosion, jamming and other problems will easily lead to equipment malfunctions and even production safety accidents. Party A has 23 portal cranes of different models, with supporting steel wire ropes covering dozens of specifications such as 30629F1+FC and 4Vx39S+5FC-40-1770, with a total maintenance length of 58,410 meters. Due to the large number of equipment, scattered distribution, complex specifications of steel wire ropes, and the extremely high requirements of shipbuilding & repair operations for equipment continuity and safety, Party A is unable to complete the standardized and professional full-process maintenance on its own, and is in urgent need of an environmental protection technology enterprise with professional technology and a sound management system to provide one-stop steel wire rope maintenance services. After multiple selections, Party A finally reached a cooperation with Shandong Dexter Environmental Protection Technology Development Co., Ltd. and entrusted it to undertake this full-series maintenance project of portal crane steel wire ropes.

• High difficulty in unified service due to large-scale maintenance and diverse specifications: 23 portal cranes are scattered in multiple operation areas, with supporting steel wire ropes of dozens of specifications and a total length of more than 58,000 meters. There are great differences in maintenance requirements for steel wire ropes in different areas and of different specifications, which requires formulating targeted construction plans, leading to high difficulty in unified promotion and management.


• Stringent maintenance quality standards directly linked to production safety: As heavy lifting equipment, steel wire ropes of portal cranes need to achieve a high-standard lubrication effect with uniform oil layer, sufficient grease penetration and no missing coating. At the same time, grease contamination to non-lubrication parts such as electrical components and brake components must be avoided. Maintenance quality directly determines the operation safety of equipment, imposing extremely high requirements on acceptance criteria and construction accuracy.


• Complex construction scenarios with prominent safety management risks: The construction areas are shipbuilding & repair factory areas involving high-risk operations such as working at heights and operations around heavy equipment. In addition, the factory areas have strict management systems for safety production, traffic and fire prevention, which put forward extremely high requirements for the qualifications of construction personnel, on-site operation specifications and safety control systems.


• High requirement for coordination between maintenance and production with the need for flexible schedule adjustment: Party A's shipbuilding & repair operations are continuous production, which cannot be shut down for a long time due to equipment maintenance. The maintenance party is required to flexibly adjust the construction schedule in accordance with the production plan, and at the same time, the maintenance of a single piece of equipment is required to be carried out efficiently to minimize the impact on normal production.


• High requirements for after-sales response and quality assurance to ensure long-term equipment operation: Party A requires the equipment to be put into use quickly after maintenance and to have long-term quality assurance. If the equipment has malfunctions related to maintenance, the maintenance party is required to respond quickly and handle them in a timely manner to avoid production stagnation caused by equipment malfunctions.

In response to Party A's core pain points, we have formulated a full-process solution featuring customization, standardization, systematization and flexibility by combining the operational characteristics of the shipbuilding and repair industry and the equipment attributes of portal cranes, providing all-round guarantee from the five dimensions of construction, quality, safety, schedule and after-sales service:

Customized Zonal Maintenance Plans to Adapt to Multi-specification Equipment Needs

According to the distribution areas of 23 portal cranes and the specification differences of steel wire ropes, we formulated a combined construction plan of robot automatic oiling and manual fine touch-up painting. Robots realize large-area and high-efficiency oiling operation for steel wire ropes, while manual fine touch-up painting targets dead corners that are difficult for robots to reach such as pulley contact sections, rope clip fixing sections and free hanging sections, ensuring that the maintenance covers all working sections of steel wire ropes without omission. In addition, in accordance with Party A's requirement of "Party A supplies maintenance materials and Party B provides construction tools", we are equipped with a complete set of tools suitable for on-site construction and completed professional commissioning to ensure construction efficiency.

Standardized All-dimensional Quality Control to Build a Solid Safety Line for Equipment

We jointly formulated the Acceptance Criteria for Steel Wire Rope Maintenance of Portal Crane Booms with Party A, setting stringent acceptance indicators from four dimensions: appearance inspection (uniformity of oil layer, integrity of coverage, no excess contamination), lubrication effect inspection (grease penetration, continuity of oil film), cleanliness inspection and equipment function verification (smooth operation). We adopted a variety of acceptance methods such as visual inspection, tactile inspection, assistance with tools like probes/small mirrors and equipment commissioning. For non-conforming items, we record specific problems and conduct unconditional rework until all items pass the acceptance, ensuring that the maintenance quality fully complies with the safety operation requirements of the equipment.

Systematic On-site Safety Management to Eliminate Potential Safety Hazards

We signed the HSSE Liability Agreement for Project Contracting Construction and Services with Party A and established a full-process safety control system. All construction personnel work with the corresponding qualification certificates as stipulated by the state, completed the factory safety training of Party A in advance and signed safety agreements, and the site is supervised and controlled by full-time and part-time safety officers assigned by us. We purchased employer liability insurance with a single person coverage of no less than 1.6 million yuan for all construction personnel, and property insurance for tools and machinery as needed, achieving all-dimensional insurance coverage for personnel and equipment. We declare and approve high-risk operations to Party A in advance and strictly abide by the factory's management systems for safety production, traffic and fire prevention, eliminating potential safety hazards from the aspects of personnel, systems and insurance.

Flexible Schedule Coordination Mechanism to Adapt to Party A's Production Rhythm

We established a flexible schedule adjustment mechanism, starting the construction with Party A's written notice for factory entry and construction, and advancing the construction efficiently at a standard of 24 hours per unit. In case of force majeure, Party A's production reasons, material problems and other factors affecting construction efficiency, the construction schedule can be postponed through negotiation with Party A, and Party A can also give a written notice to change the service time one week in advance. This maximally cooperates with Party A's continuous production operations and achieves seamless coordination between maintenance construction and enterprise production.

Full-cycle Quality Assurance and Fast After-sales Service to Ensure Long-term Equipment Operation

We set an extended warranty period of 12 months. For steel wire rope malfunctions caused by our construction quality problems within the warranty period, we are responsible for free repair or replacement within 7 days. We established an ultra-fast after-sales response mechanism: if Party A's equipment has malfunctions related to maintenance within the warranty period, we will provide professional replies within 24 hours; if the problem cannot be solved by phone, after-sales personnel will arrive at the site for handling within 36 hours, avoiding the impact of equipment malfunctions on Party A's production. In addition, we adopt a standardized settlement model of "advance payment + payment upon qualified acceptance + quality guarantee deposit", where the quality guarantee deposit accounts for 5% of the settlement price and will be paid without interest upon the expiration of the warranty period and in the absence of quality problems. This balances the rights and interests of both cooperating parties and achieves win-win cooperation.