Vietnam Export Project Case: A193-B7+2H PTFE-Coated Fastener Kit Solves Thread Galling for Export Stamping Complete-Set Equipment

In the export sectors of pressure vessels, complete piping equipment, and heavy-duty stamping equipment, flange fasteners are core supporting components that directly determine the on-site operation stability of equipment, the convenience of maintenance, and the delivery reputation of overseas projects. Many complete equipment export enterprises that cooperate with Vietnam and other Southeast Asian regions have long been plagued by two major on-site problems, which are also the key pain points that most easily lead to point deductions and increase after-sales costs in stamping complete equipment projects:

1.Pain points in working condition operation and maintenance: High-temperature corrosion prone to seizing: Projects in Southeast Asia are subject to perennial high temperature, high humidity and high salt spray, and ordinary flange fasteners are highly susceptible to thread corrosion and galling seizing under high-temperature and high-pressure working conditions. They cannot be disassembled normally during annual equipment maintenance, and can only be removed by destructive cutting, which not only scraps the accessories, but also damages the flange contact surface, resulting in shutdown, rework and high maintenance costs.

2.Pain points in export delivery: Vulnerable to wear and tear during sea freight: For traditional fasteners in bare packaging, their threads are extremely prone to collision scratches and thread profile deformation during long-distance sea shipping, multiple loading and unloading, as well as warehouse turnover. After arrival at the port, they fail to meet the assembly accuracy requirements, directly resulting in on-site rework, replacement and replenishment orders, as well as project schedule delays.

3.Equipment operation and maintenance challenges: When equipment operates under long-term high-temperature and salt spray corrosion conditions, ordinary fasteners are highly prone to thread seizure and corrosion failure, leading to great difficulty in disassembly and assembly during later maintenance, high repair costs, and a serious impact on the service life of the equipment.

4.Maritime delivery challenges: The threaded parts are shipped in bare packaging without any protection. During long-distance ocean shipping and multiple loading/unloading operations, the threads are highly prone to collision damage and profile wear, which renders the goods unfit for normal assembly upon arrival at the port, directly delaying the project schedule and incurring extra costs for replacement and wastage.

Based on years of experience in the export of complete sets of heavy industry supporting equipment, most of the above problems are not caused by equipment operating conditions exceeding the standard, but by scattered and mixed procurement, inconsistent accessory standards, and surface processes that do not match the operating conditions. Two common pitfalls in this industry require particular attention to avoid:

• Separate sourcing and mismatched combinations with mechanical incompatibility: Most enterprises separately purchase studs, nuts, and gaskets, and source supplies by piecing together products from multiple manufacturers. When A193-B7 high-temperature and high-strength studs are paired with ordinary low-strength nuts, their hardness, heat resistance and preload bearing capacity do not match, which is extremely prone to loosening and leakage risks under long-term high-temperature pressure.
• The craftsmanship is rudimentary and cannot withstand overseas working conditions: it adopts ordinary galvanization and blackening treatment, featuring weak anti-corrosion performance and high friction coefficient, thus failing to adapt to the salt spray corrosion environment in Southeast Asia, and rusting and seizing failure will occur after short-term use.
• Digging deep into the root cause of the problem, it mainly stems from the non-standard procurement practices of the industry, which is also the core pitfall to avoid in heavy industry export projects:
• Purchasing of split components with inconsistent standards: Most manufacturers separately purchase studs, nuts and washers, and the heat treatment, machining accuracy and surface treatment processes vary greatly from one manufacturer to another, resulting in incompatible performance of the entire set of components.

In response to the inelastic demand for the export of complete pressure vessel and pipe stamping equipment, we provide an integrated complete supporting solution consisting of A193-B7 fully threaded studs, A194-2H heavy hex nuts and GB97 gaskets, delivered as a complete set from the same factory with the same process to eliminate the risks caused by mixed matching. The main specification for this batch export project to Vietnam is M24*300 standard part, and the detailed product specification parameters are as follows:

1.Complete Set Configuration: A193-B7 fully threaded studs, A194-2H heavy hex nuts, GB97 national standard carbon steel flat washers; the entire set is shipped as a matched assembly, with no externally sourced or cobbled-together components.

2.Product Specification: M24×300mm fully threaded stud, precision full-thread machining, suitable for through-hole assembly of flanges on large pressure vessels and high-pressure pipelines.

3.Implementation standards: Stud bolts conform to ASTM A193 Gr. B7, nuts conform to ASTM A194 Gr.2H, and gaskets comply with Chinese national standard GB97; this product meets both US and Chinese national standards, making it suitable for acceptance of overseas projects.

4.Surface treatment: full-body blue PTFE Teflon coating, featuring low friction, high temperature resistance and salt spray resistance, suitable for the hot, humid and corrosive working conditions in Southeast Asia.

5.Exclusive Transportation Protection: Equipped with a standard blue mesh threaded protective sleeve that fully covers the thread profile, it is specially designed to reduce bumps during sea transportation and abrasion during loading and unloading, ensuring the thread precision remains intact.

Compared with scattered procurement and ordinary process accessories, this PTFE-coated complete flange assembly perfectly meets the export requirements of complete stamping equipment, and its core supporting advantages are reflected in three aspects:

• Adapt to high-temperature and high-pressure working conditions and prevent thread seizure: the PTFE coating significantly reduces the thread galling friction coefficient, solves the problems of thread cold welding and jamming under high-temperature working conditions, ensures smooth disassembly and assembly during later equipment maintenance without destructive removal, and greatly reduces the operation and maintenance costs of overseas equipment.
• With excellent resistance to salt spray corrosion, it is ideal for coastal export projects: Compared with traditional galvanizing and Dacromet processes, the blue Teflon coating delivers better performance in acid and alkali resistance, anti-aging and salt spray resistance. It can adapt to the harsh high-humidity, high-salt-spray environments in Vietnam and other Southeast Asian regions for a long time, thus extending the service life of the flange connection system.
• Full mechanical matching ensures more stable equipment operation: the mechanical grade of B7 studs and 2H nuts is precisely matched, and the GB97 gaskets are used to evenly distribute assembly pressure, protect the flange sealing surface, avoid loosening and leakage during long-term operation, and ensure the stable commissioning of complete sets of equipment.
• Transportation Protection Configuration: Exclusive blue mesh threaded protective sleeve, which fully covers and protects the precision threads to ensure damage-free delivery via long-distance ocean shipping.

Leveraging the advantages of Jiaxing Aoke Hardware's Localization supporting production, we are fully capable of undertaking the complete delivery business of A193-B7 series flange fasteners, and our supply capacity is fully adapted to the needs of overseas projects:

1.Spot Goods for Fast Delivery: We maintain year-round stock of mainstream specifications commonly used in overseas projects such as M24*300, support fast order scheduling and shipment, and cater to the needs of urgent projects.

2.Non-standard Customization Service: We can customize various non-standard length, special coating and high-precision fastener assemblies according to customers' equipment drawings, on-site working conditions and project acceptance standards.

3.Whole-process quality inspection guarantee: the products go through multiple procedures including dimension verification, hardness testing, coating thickness detection and appearance screening before delivery, and MTR material reports and quality inspection certificates can be provided for each batch, which meet the acceptance standards of various heavy industry export projects.

4.Flexible batch delivery: It supports small-batch sample testing and full-container bulk export, and adapts to various delivery scenarios for overseas engineering projects in Vietnam and Southeast Asia.