Objectives

The primary objective of this tender is to appoint a panel of three (3) qualified contractors to perform maintenance of power transformers at various substations over a period of three (3) years on an as-and-when basis. The aim is to establish a reliable and competent service provider panel capable of conducting oil analysis, temperature monitoring, load management, cleaning, connection tightening, bushing inspection, and comprehensive testing in accordance with relevant standards.

Scope

The scope encompasses the establishment of a panel of three suitable service providers responsible for maintenance of power transformers up to 30 MVA. The work includes:

• Oil analysis and testing
• Temperature monitoring
• Load management
• Cleaning and tightening of connections
• Bushing inspection
• Comprehensive testing adhering to SANS and IEC 60076 standards
• On-site and workshop refurbishment/repairs
• Transportation, storage, and installation of transformers
• Provision of documentation, warranties, and quality control reports

The maintenance activities will be conducted at various substations, with specific standards and safety protocols to be followed throughout the contract period.

Technical Requirements

The technical requirements include:

• Compliance with South African National Standards (SANS) and IEC 60076 standards
• Provision of accredited workshop testing facilities (SANAS or equivalent, ISO 9001 & 14001)
• Availability of necessary equipment for oil sampling, testing, and transformer repairs
• Capability to perform routine and specialized electrical and mechanical tests (e.g., winding resistance, ratio, insulation resistance, SFRA, impulse withstand, DGA)
• Proper workshop facilities for disassembly, drying, core winding, bushings repair, sandblasting, and painting
• Qualified personnel with relevant experience and certifications
• Provision of detailed documentation including test reports, warranties, and impact recordings
• Adherence to safety, health, and environmental regulations

Skills and Qualifications Requirements

The successful bidders must demonstrate:

• Previous experience in power transformer maintenance, preferably with contracts exceeding R2 million
• Ownership or access to workshop facilities equipped for transformer repairs and testing
• Valid SANAS accreditation for transformer testing facilities
• ISO 9001 and ISO 14001 certifications for quality and environmental management
• Qualified and trained personnel, including certified electricians, riggers, and medical fitness certified workers
• Capability to conduct all electrical, mechanical, and oil analysis tests in accordance with standards
• Proven safety record and compliance with occupational health and safety regulations
• Ability to provide comprehensive documentation, including test reports, warranties, and safety files
• Financial stability evidenced by bank ratings and viability assessments