On-site maintenance and refurbishments

We guarantee comprehensive support services for all maintenance operations required by active transformers using Shell or Core technology. Our team’s skills, combined with the resources we use, make it possible to provide any type of service that may be needed whether in corrective maintenance, in particular after a breakdown, as well as preventative maintenance.

For example, preventive maintenance operations are transformer refurbishments that involve replacement of seal, replacement of bushings and other accessories, restoration of cabinets, oil top-ups, and oil treatments. The tap changers are also checked, both on-load and off-load.

Replacement of Bushings

Cameroon – Hydraulic power plant of Songloulou Refurbishment 13 x 38 MVA – 1Ф 10.3 / 225 kV :

Before Refurbishment

After Refurbishment

France : EDF – Hydraulic power plant “La Figère” -Transformer TR 40 MVA – 225 kV of 1963 :

Before Refurbishment

After Refurbishment

Active parts repairs

JST transformateurs Services provides customers with turn-key repair solutions by enabling them to take advantage of the expertise of a major manufacturer of both Core and Shell type technologies.

Our teams are able to perform on-site evaluations of defective devices and recommend the most appropriate repair solutions, taking into consideration both cost and time. Repairs may be performed either on-site in a local workshop (untanking room) or in our own workshops, depending on the situation. In France, we are able to carry out repairs both in our factory in Lyon and in our new workshops with a surface of 200 square meters.

Iceland: 75 MVA – 225 kV Core technology

France: 33 MVA – 63 kV
Core technology in workshop in Lyon

France: 70 MVA – 225 kV Shell type in workshop

Workshop / Repairs in Chalon-sur-Saône

Cameroon: Core technology 38 MVA – 10.3 / 225 kV

Spare parts and oil analysis

Spare parts:

Thanks to the comprehensive database that we have built during our 50 years in the business, including Jeumont, SW, Jeumont Schneider, Jeumont Schneider Transformateurs, VA Tech JST, and JST transformateurs devices, it is easy for us to quickly identify the serial numbers and part numbers, as well as plans and documents related to the specific piece of machinery.

In addition to the stock of common parts, we also offer our users a catalogue of over 10,000 products.

Contact : + 33 4 78 77 88 44 / +33 4 78 77 88 93

Oil Analysis:

Our group applies its expertise and cutting-edge technology to offer advanced oil testing services for your devices. This service is accompanied by reliable troubleshooting, provided by our specialists.

Oil sampling set

View of laboratory with chromatography device

Contact: + 33 4 78 77 88 44 / +33 4 78 77 88 93

Assessments, audits and trainings

Audits and Assessments:

Preventive maintenance audits aim to assess the pertinence of the scheduled maintenance operations. For example, these audits involve reviewing the efficiency of the team in place, their compliance with established procedures, and the frequency of oil tests. Technical modification audits focus more on the functionality of the transformers rather than on the human factor. These are used to indicate whether or not it would be beneficial to replace the connection type or the cooling method or even to increase the power of the devices.

Live part evaluations, which are performed using endoscopy, indicate the degree of wear affecting a device in operation.

Trainings :

JST transformateurs Services offers two types of training sessions, based on programs that are adapted to client needs and are provided on an à la carte basis: factory-based training (design, manufacturing, testing, etc.) and on-site training (installation, maintenance).