MAFUTA TRANSFORMERS

MAINTENANCE ON HT TRANSFORMERS AND SWITCHGEAR

AND

INFRA-RED SCANNING

SERVICES

SERVICES

TRANSFORMER SERVICES

We specialize in the installation and

commissioning of all transformers

but also provide the following

service:

•

Repairs on transformers such as

Oil leaks, tap changers, bushings

Connections, cone rubbers, gaskets, etc.

•

Rewinding of transformers.

•

Testing of transformers (Full

commissioning tests can also be

done, if requested).

•

Cleaning of transformers

•

Spray painting of transformers

•

Purification of transformer oil ( we

attend to the purification of the

oil, either off-line or on-line)

•

Onsite regeneration of

transformer oil

•

Supply and delivery of mini-subs.

Sight glasses, breathers, Bucholtz relays, pressure relays, etc.

•

Tests:

Oil sampling

Megger Insulation Test

Ratio test

•

Operation Verification:

Check Bucholtz Relay operation

Check Temperature Relay operation

Check Pressure Relay operation

•

Repairs:

Tap changers, gaskets, bushings, sight glasses, breathers, etc

•

We also buy and sell

transformers

POWER FACTOR CORRECTIONS

Installation

•

Repairs

•

Maintenance

PURIFICATION OF TRANSFORMER

INSULATING OILS

The following specifications describes

the plants used by Mafuta for the

filtration of transformer insulating oil.

The purifiers are designed for filtration

of transformer oil in workshops, storage

tanks, drums or directly in transformers.

Purification of oil in transformers can be

carried out off-load or on-load

depending on customers' preference.

Water Removal:

Water is removed by heating the oil

passing it through coalesces inside a

vacuum chamber. During this process

water and oil are separated and clean

dry insulating oil are returned to the

transformer.

Gas Removal:

During the vacuum stage of the process

all dissolved gasses are removed from

the oil, leaving it clean, dry and gas free.

Oxygen, as an accelerator of oxidation,

is also removed.

Particulate Matter Removal:

98% of all particles over .5 micrometer is

removed.

Dielectric Strength:

Improvement in dielectric strength, up

to 70 kV, with new oil.

INFRA-RED SCANNING

Infra-Red Scanning on all size DB Boards

- Small

- Medium

- Large

•

Reports Included

•

Scanning:

- Cables

- Substations

- Transformers

- Switchgear

- Etc.

SWITCHGEAR SERVICE

Our services also include the following

pertaining to switchgear:

•

Service and Repair of HT Circuit

Breakers.

•

Retro Fitting of HT circuit

breakers.

•

The servicing and testing on all

relays and CT"s.

•

Cleaning and Painting of

Substations.

•

Service of Battery Trip Units.

•

Installation and commissioning of

HT circuit breakers.

•

Servicing of bearings, Functionality Test, Lubrication, Speed test, etc

•

Testing of Micro Ohm, Pressure, etc

•

Oil change on OCB’s

All repairs Meg

•

Protection:

Trip coils

SF 6 Gas pressure Switch

Closed coils

•

We also buy and sell HT circuit

breakers, vacuum breakers and

gas breakers.

CABLES

(400 V – 33 KV)

SWAC / PILC / XLPE

•

Testing:

Pressure test

Megger Insulation test

•

Cable fault finding.

Fault location (Thumping Test)

- Faulty or blown cables

Jointing

- We qualify worldwide to do up to 33 kv

Terminations

- (Making of cable ends)

CABAC / RAYCHEM

UPGRADES

From Oil to SF 6

From SF 6 to Vacuum

CARRIAGES

PLEASE NOTE THAT ALL MAJOR REPAIRS ARE DONE OFFSITE.

OIL SAMPLING

Transformer oil test can be classified as

follows:

•

The full test done on transformers

include kV tests, moisture tests,

DGA tests as well as the testing of

acidity levels within the oil.

•

The normal tests done on

transformers include only kV

tests, moisture tests as well as the

testing of the acidity levels within

the oil.

•

PCB exact count (ppm).

•

Furanics test.

•

Tan Delta and interfacial tension

as well as others.

Contact our company for more information on the types of tests that can be

performed.

SUBSTATIONS

Maintenance contracts quarterly

- Visual Inspection

Maintenance contracts Bi-Annual

- Settings and trip testing

Maintenance contracts Annual

- Full Function Testing

•

Protection:

Voltage Tx’s – Fuses

Current Tx’s – Primary CT Testing

Battery Tripping Units – Water & Charger

Protection Relays – Secondary Injection Testing

Over Current Test

RAYROLL

Change selected Rayroll Breaker into a Motor charged and have a closing remote installed.

OTHER SERVICES

•

Consulting.

•

24/7 Emergency

•

OUR WORK

TRANSFORMER MAINTENANCE

Mafuta Transformers offers a maintenance program designed specifically to maximize the useful life of transformers. We try to save customers millions of rands in untimely repairs & premature transformer replacements by recognizing the advancements of oil oxidation, paper decay and internal overheating before significant harm & irreversible damage is done.

Our problem is centralized around annual oil sampling & through visual inspissation of your transformers. Mafuta Transformers experienced analysts review every laboratory, and inspection checklist. A transformer diagnostic report is provided which included a prioritized list of maintenance recommendations & comprehensive cost calculation that will direct attention to the most necessary actions.

TESTING & PROBLEM ANALYSIS

It's a well-known fact that regular oil analysis is extremely useful in monitoring the condition of many types of oil. The same can be said for transformer oil. Oil sampling results can accurately diagnose problems & make related corrective recommendations.

Many types of faults can be discovered before they become serious failures & outages can potentially be avoided. Mafuta Transformers make use of an independent oil laboratory for your piece of mind.

MECHANICAL REPAIRS

Gasket replacement, gauge replacement, silica gel and breather replacement, blasting and painting, valve replacements, bushing repair or replacements are all typical examples. Mafuta Transformers has equipment, experience & knowledge to conduct all transformer repairs.

OIL CONDITIONING

Our oil purification plant is among the most efficient & technologically advanced in S. A. While our expertise to perform these services is second to none. If filtering of your oil is necessary we will circulate the oil with a minimum of 4 circulations, this will add longevity to the life of your transformer, preventing costly replacement or down time.

TRANSFORMER OIL ANALYSIS

The following are some common tests performed through Mafuta Transformers by an independent laboratory on electrical transformer oil:

MOISTURE CONTENT

One of the most important functions of transformer oil is to provide electrical insulation. Any increase in moisture content can reduce the insulating properties of the oil, which may result in dielectric breakdown. The moisture content of the oil is determined Coulametric Karl Fischer Instrument.

ACID NUMBER

Transformer oil is oxidized under the influence of excessive temperature & oxygen, particularly in the presence of small metal particles which can act as catalysts. Reaction of these acids with the bulk oil can result in sludge. The oil canals can become blocked and the transformer can heat up. An increase in acid goes hand in hand with a decrease in dielectric strength & increased moisture content.

DIELECTRIC STRENGTH

This measures the oil's ability to with stand electrical stress without failure. Any significant reduction in the dielectric strength will indicate that the oil is no longer able to perform this vital function.

DGA

Dissolved gas analysis has become a standard in electrical maintenance industry throughout the world & is considered as the most important test .It is important to understand that the DGA test allows you to determine any arcing, sparking & overheating inside your transformer .It's not an oil test; however an oil sample is used as a widow inside the electrical apparatus that helps with troubleshooting potential problems.

PCB

Poly chlorinated Biphenyls are a group of synthetic oil like chemical of the organ chlorine family. Until their toxic nature was recognized & their use was banned in the 1980's they were widely used as insulation in electrical equipment .Transformer oil that has been tested should be classified as contaminated until shown to be otherwise. This can be done by fixing a sticker onto the transformer.

ONE -STOP SHOP

Mafuta Transformers provides diagnostic testing services & maintenance, including infra-red scanning laboratory purification. Should you not recognize a service required by your company do not hesitate to contact us for any information.

SAMPLE CLIENT

Industrial
Commercial
Hospitals
Hotels
Municipalities
Mining

24 HOUR EMERGENCY SERVICE

For your convenience we have implemented a 24 hour service, which means you may contact our hard working individuals at any time to assist in breakdown situation.

GUARANTEE

All workmanship carries a 6 month guarantee

Mafuta Transformers can play a vital role in preventing unscheduled outages in electrical transmission & distribution equipment by determining the condition of the equipment itself and correcting the problems, including the oil, gaskets & paper insulation. Regular routine oil analysis & servicing of your transformers should be the cornerstone of any oil filled electrical maintenance program.

ABOUT US

ABOUT US

In the fast pace production driven world, keeping electricity on all the time is something that can no longer be taken for granted.

We, at Mafuta Transformers, strive to do just that, keeping electricity on all the time. Our business offers expertise services and products that are geared towards extending

substation primary plant life maintenance.

What Drives our Business: Value

Mafuta Transformers has creative and empowered people that are able to connect our business purpose and values with our customers and other external stakeholders. Our organization has tailor made products and services that deliver the following value to our customers:

We minimize production losses due to unplanned outages.
We keep your plant in optimum condition.
We maximize plant life.
We enable you to understand all the risk associated with your plant.
Our people stand apart from the rest by their passion for what they do, by being alert to possibilities and by their enthusiasm to invent new ways into the future.
Cost ± Every Cent spent saves a R1 000.00 on Production

Mafuta Transformers believes that value and cost are inseparable.
To drive up the perception of value, a company must simultaneously drive down the cost.

Falling cost benefit customers. More so, Falling cost give us better margins for profit and give us sustainable competitive advantages