Class NK Approved Welder Qualification in Vietnam

Bacviet Commercial and Shiptech Company (Bacviet Shiprepair) is one of the leading Class-approved ship repair and marine engineering companies in Vietnam, providing comprehensive technical services for vessels at all major ports and anchorages such as Haiphong, Cai Lan, Cam Pha, Dung Quat, Son Duong, Nghi son and Phu my.

We are officially approved by Class NK (Nippon Kaiji Kyokai) for Welder Performance Qualification (WPQ) and Welding Procedure Specification (WPS) according to Part M, Chapter 5 of the Rules for the Survey and Construction of Steel Ships.
This approval demonstrates Bacviet’s technical capability and strict compliance with international classification standards.

 1. Overview of Class NK Welder Qualification

Class NK is one of the world’s most respected classification societies under the International Association of Classification Societies (IACS).
To obtain Class NK Welder Qualification, welders must pass a rigorous testing process that includes visual, radiographic, and mechanical examinations to verify weld integrity and compliance with Class standards.

At Bacviet Shiprepair, our welding personnel are trained, tested, and certified by Class NK surveyors for steel plate welding within a range of 9.0mm to 36.0mm thickness and across all major welding positions:

• 1G (Flat / PA)

• 2G (Horizontal / PB)

• 3G (Vertical Up / PE)

• 4G (Overhead / PD)

This range ensures our welders can perform safe and high-quality work on a wide variety of ship structures — from hull plating to deck reinforcement and equipment foundations.

2. Range of Approved Welding Qualification

Welding Process:

• SW (Semi-Automatic Welding) using CO₂ shielding gas.
  This process provides excellent penetration, reduced spatter, and consistent weld quality for carbon steel applications.

Product Type:

• Steel Plates (P) with thickness 9.0mm – 36.0mm,
  covering grades KA, KB, KA32, and KA36, suitable for hull, deck, and structural fabrication works.

Type of Welded Joint:

• Butt Weld (B) — Single side butt weld with backing (ss mb), which ensures strong root penetration and structural durability.

Base Metal:

• Carbon Steel (CS) used for hull and general ship structures.

Qualified Welding Positions:

• Flat (PA), Horizontal (PB), Vertical (PC/PE), Overhead (PD), Horizontal Overhead (PD).

All qualifications are approved directly by Class NK surveyors at Bacviet’s workshop in Hai Phong City, ensuring full traceability and authenticity.

3. Applications of Class NK Approved Welding

Our Class NK qualified welders perform essential work onboard and in shipyards across Vietnam, including:

• Hull & Structural Renewal:
  Renewal of side shell plating, deck sections, tank bulkheads, and bottom plates under Class supervision.

• Aluminum and Steel Fabrication:
  Construction of ladders, platforms, handrails, and accommodation structures.

• Machinery Foundation Fabrication:
  Welding for main engine foundations, pump beds, and auxiliary equipment mounts.

• Deck Equipment & Outfitting:
  Gangway and pilot ladder support fabrication, mooring bitt renewal, windlass base welding.

• Pressure Vessel and Piping Works:
  Piping repair, hydro test, and Class verification for cargo lines and ballast systems.

Every welding activity is documented and accompanied by Welding Records, WPS, WPQ Certificates, NDT reports, and Class attendance certificates as per international standards.

4. Advantages of Class Approved Welding in Ship Repair

1. Guaranteed Safety & Compliance
   – Ensures all welding meets international marine safety standards (IACS, IMO, SOLAS).

2. Class Acceptance Worldwide
   – Repairs performed under Class NK are automatically recognized by other IACS members such as DNV, ABS, LR, BV, KR, and RINA.

3. Higher Reliability
   – Reduces risk of structural failure and ensures longevity of ship hulls and components.

4. Documented Traceability
   – Every weld joint and procedure is traceable through Class-approved documentation.

5. Added Value for Shipowners
   – Enhances vessel credibility during PSC inspection, resale, or chartering.

⇒ CLASS NK'S WELDING PROCEDURE SPECIFICATION IN VIETNAM

⇒ LLOYD'S REGISTER'S WELDING PROCEDURE SPECIFICATION IN VIETNAM

5. Samples of Class NK Certificates

Bacviet Shiprepair maintains a team of certified welders with individual certificates issued by Class NK.
Below are sample certificates:

# Image for Welder Certificate No.1 approved by Class NK - Thợ hàn Đăng kiểm NK - Bacviet Shiprepair Company

# Image for Welder Certificate No.2 approved by Class NK - Thợ hàn Đăng kiểm NK - Bacviet Shiprepair Company

# Image for Welder Certificate No.3 approved by Class NK - Thợ hàn Đăng kiểm NK - Bacviet Shiprepair Company

# Image for Welder Certificate No.4 approved by Class NK - Thợ hàn Đăng kiểm NK - Bacviet Shiprepair Company

6. Related Welding Procedure Specifications

Bacviet Shiprepair is not only approved for individual welder qualifications but also for full Welding Procedure Specifications (WPS) and Procedure Qualification Records (PQR) under different classification societies:

• Class NK – Welding Procedure Specification (WPS) – Vietnam

• Lloyd’s Register (LR) – Welding Procedure Specification (WPS) – Vietnam

• Bureau Veritas (BV) – Approved Workshop for Steel Structure Fabrication

These procedures cover both manual and semi-automatic welding processes for carbon and stainless steels.

7. Why Choose Bacviet Shiprepair

+ Class-Approved Workshop: Certified by major IACS members (DNV, NK, BV, LR, KR, VR).
+ Qualified Welders & NDT Team: With CO₂ and SMAW processes for hull & structure repair.
+ 24/7 Availability: Teams can mobilize to any port or anchorage in Vietnam.
+ Strong Documentation Support: Class attendance, reports, and certificates ready within hours.
+ Trusted by Global Clients: Serving international fleets such as NYK, MOL, Oldendorff, and Maersk.

8. Frequently Asked Questions (FAQ)

Q1. What does “Class NK Approved Welder” mean?
It means the welder has passed the official Class NK test and can perform welding works on vessels under the survey of Class NK or other IACS members.

Q2. Are Class NK certificates accepted by other classification societies?
Yes. Class NK is part of IACS, so qualifications are recognized by other societies such as ABS, DNV, BV, LR, KR, and RINA.

Q3. Can Bacviet’s welders perform work onboard during voyage repairs?
Yes. Our mobile repair teams can embark and perform certified welding, inspection, and Class attendance at any anchorage or port in Vietnam.

9. Contact Bacviet Shiprepair (24/7 Service)

Company: Bacviet Commercial and Shiptech Company (Bacviet Shiprepair)
Address: 25/6/302 Van Cao Street, Hai Phong City, Vietnam
Mobile / WhatsApp / WeChat: +84 904 125 520
Email: bacviet@haiphongshiprepair.com
Website: https://haiphongshiprepair.com