SUBMARINE CABLE MAINTENANCE DEDICATED SHIP – A … · Jorge de Souza Santos, Gilvan Jordão de...

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SUBMARINE CABLE MAINTENANCE DEDICATED SHIP – A SUCCESS STORY OF EMBRATEL (BRAZIL) FROM THE

PERSPECTIVE OF CUSTOMIZATION, RESPONSE TIME AND COSTS Jorge de Souza Santos, Gilvan Jordão de Castilho (Embratel) Email: <[email protected]> Embratel – Rua Senador Pompeu, 119, 4º andar, Centro, Rio de Janeiro, CEP: 20221-291, Brasil Abstract: Embratel submarine optical plant is composed by two parts: the international cables that are maintained by the Atlantic Maintenance Wire & Repair Agreement (ACMA), and the national systems, that are under a local specific contract. This presentation will focus on the national submarine cables maintenance, where we will share experiences, highlighting: 38 repair operations through the last 13 years. We will analyse the main causes of cable failures, mitigating actions and recovery time. Finally, we will compare projections between ACMA maintenance and a dedicated ship one. 1. INTERNATIONAL CABLES –

ACMA’s MAINTENANCE Americas II The Americas II submarine cable, is 4859.6 nm (9,000 km) long, has 8 (eight) optical fibers, connecting Brazil, French Guiana, Trinidad and Tobago, Venezuela, Curacao, Martinique, Puerto Rico and USA. It became operational in September, 2000. Atlantis-2 This cable, with 7073.4 nm (13,100 km) of extension, four optical fibers being two used for service and the other two for restoration, connects Argentina, Brazil (from Natal to Rio de Janeiro), Senegal, Cape Verde, Canary Islands and Portugal and entered in operation in 1999. Embratel also implanted, for its exclusive use, another four additional optical fibers between Fortaleza and Rio de Janeiro. Unisur With 940.1 nm (1,741 km) of extension, operational since November, 1994, the system of telecommunications UNISUR interconnects the countries of Mercosul, Argentina (Las Toninas), Brazil (Florianopolis) and Uruguay (Maldonado).

2. NATIONAL SYSTEMS - MAINTAINED BY LOCAL CONTRACT AND DEDICATED SHIP

Rio de Janeiro – São Mateus; Porto Seguro – Natal and São Paulo – Rio de Janeiro There are 3 systems, with total extension of 1588 nm (2941 km) and interconnect the city of Santos (southeast of the country) and all the coastal capitals until the city of Natal (northeast of the country). Rio de Janeiro - São Mateus With 448.7 nm (831 km) it was inaugurated in December, 1996. • cable’s types – Pirelli SA (11,2%), DA

(85,2%) and DAT (3,6%); • type and amount of fibers - DS type, 18

optical fibers; • protections (73%) – buried at minimum

3.3 ft (1 meter), articulated ducts, fixation pins (in rocks) and underwater bridges;

• maximum depth of 315 ft (96 meters); • maximum shore distance 17.2 nm (33,9

km); • crossing other’s installations (cables, oil

and gas ducts).



Figure 1 - Embratel submarine cable map

Porto Seguro - Natal With 877.4 nm (1625 km) it was inaugurated in December, 1996. • cable’s types – Simplex HSA (67,1%), DA

(31,6%) and RA (1,3%); • type and amount of fibers - DS type, 18 optical

fibers; • protections (12,2%) – buried at minimum 3.3 ft

(1 meter), articulated ducts, fixation pins (in rocks) and underwater bridges;

• maximum depth of 183.7 ft (56 meters); • maximum shore distance 14.0 nm (26,5 km); • crossing other’s installations (cables, oil and

gas ducts). São Paulo - Rio de Janeiro With 261.9 nm (485 km) it was inaugurated in March, 1999.

• cable’s types – Pirelli SA (75%) and DA (25%);

• type and amount of fibers - STD type, 24 optical fibers;

• protections (35%) – buried at minimum 3.3 ft (1 meter), articulated ducts, fixation pins (in rocks) and underwater bridges;

• maximum depth of 190.3 ft (58 meters); • maximum shore distance 22.7 nm (42,2

km); • crossing other’s installations (cables, oil

and gas ducts).



3. OPERATIONAL HISTORY At first, a study to define the model to be implemented has been carried out, exploring 3 possible hypothesis of maintenance: ACMA (consortium model); dedicated ship and ship of opportunity. This study had considered products and services offered by the market, the inherent risks due the geographic localization of the systems, the possible performance for each one of the 3 hypothesis and the costs involved. Then had been concluded that dedicated ship solution would make possible to reach the levels of desired availability and performance. 4. WORK PHASES

4.1. Phase I – 1998 to 2003

Major data for the bid and contract On the basis of the following specifications, the services had been bid on and contracted.

1. Ship

• equipped with systems of localization, collect, relaunch, tests and joint of submarine optical cables;

• ROV (Remotely Operated Vehicle); • DPS (Dynamic Positioning System); • service speed – 10 knots at Beaufort 4; • support systems – communications,

computers, etc. 2. Services

• repair time (Table 1); • joint (permissible maximum loss of 0,1 dB); • spares (joint kits and optical cables) storage; • joint kits supply; • spare cables annual periodic tests; • on board room for 3 Embratel

representatives. 3. Stated period (renewable)

5 years (ending February 2003). 4. Payment

Standing charges plus running costs (during operations).

5. Contract Model Dedicated ship with focus in a Service Level Agreement (SLA) according to repair’s type and the stages of the work.

Table 1 - Phase I

Repair Type Maximum Repair Time (days)

Laid cable 9 Buried cable 12 Shore end with ship 17

Shore end without ship 12

Additional protections 10

Evaluation of Phase I This had been a phase of increasing experiences in submarine cable repair for Embratel as well for the contracted company. During this phase, 13 operations had been made and the uses of Remotely Operated Vehicle (ROV) had been revealed as unnecessary. In the cases where the cable had to be reburied, divers had been successfully used. Two situations had been the causes of those repairs: ship’s anchorage (4) and fishing activities (9) (Table 2). In this period also occurred a change in the Brazilian telecommunications sector context. Embratel had been privatized under the control of the MCI (American company), later merged into the MCI WorldCom. At that time accumulated negative financial results had determined a reduction in its operational costs and a revision in this maintenance contract model. The new model had focus in the guarantee of a SLA for the total recovery time, without specifying times to the stages of the work, neither establishing the compulsory use of specific resources.



Table 2 - Phase I - Events

Cause System Events

Buried cable

Laid cable Anchorage Fishing Theft

No Identified

Rio de Janeiro ‐ São Mateus

2 2 0 2 0 0 0

Porto Seguro ‐ Natal 7 1 6 2 5 0 0 Rio ‐ São Paulo 4 0 4 0 4 0 0 Total 13 3 10 4 9 0 0

4.2. Fase II – 2003 to 2008

Major data for the bid and contract On the basis of the following specifications, the services had been bid on and contracted. 1. Services

• repair time (Table 3); • joint (permissible maximum loss of

0,1 dB); • spares (joint kits and optical cables)

storage; • joint kits supply; • spares cables annual periodic tests; • on board room for 3 Embratel

representatives.

2. Stated period (renewable)

1 year (ending February 2004). 3. Payment


4. Contract Model Focus in SLA for the total operation, without specific equipages requirements neither previous permission for the ship be used in other activities, instead of being

dedicated - standby during the period between repairs. Evaluation of Phase II The knowledge acquired on the previous phase has been transformed into a governance system - operational procedures and routines. The operation planning has been improved as well as the documentation system about the operations – data from the contracted company and Embratel, besides the Daily Reports. An Instruction Manual for the inspectors on board has been elaborated. The consumption of spares parts (cables) started to receive special attention with a handling and use planning of the cables in order to minimize the remainders for discarding. Contacts has been established with other telecommunications companies, Petrobras (oil and gas company) and cities public administrations (oceanic launching of dejections) to exchange information about the crossing and neighborhoods of installations. Contacts also have been established with port authorities and, through these, with representatives of workers and employers of the fishing work, informing them on cables installations, the importance of the telecom services and the need to conserve its integrity. The changes in the contract model did not brought degradation of the operations. Despite all changes the average time of maximum repair remained the same.

Table 3 - Phase II

Segment Maximum Repair Time (days)

RJO - SPO 15 RJO - SMT 15 PGU - NTL 22



In this second phase, 15 repairs have been made. Two situations are the causes of 13 repairs: ship’s anchorage (5) and fishing activities (8). In 2 other events the causes has not been identified. In the case where it was necessary to rebury the cable, divers have been successfully used. (Table 4) The results of mitigating actions to reduce damages caused by fishing activities still remain weak because this is a predominantly sprayed amateur activity.

In 2004, under control of the Telmex group, in a new social-economic environment, it was necessary, once more, to reduce costs. Also, the activities in the oil and gas industry increased and, due to this, the repair ship rescinded contract. So, it was necessary to search for another new solution.

Table 4 - Phase II - Events Cause

System Events Buried cable

Laid cable Anchorage Fishing Theft

No Identified


4 1 3 3 1 0 0


4.3. Fase III – after 2008

Major data for the bid and contract On the basis of the following specifications, the services had been bid on and contracted. 1. Services

• repair time (Table 5); • joint (permissible maximum loss of

0,1 dB); • spares (joint kits and optical cables)

storage; • spares cables annual periodic tests.

Table 5 - Phase III

Segment Maximum Repair Time (days)

RJO - SPO 24 RJO - SMT 24 PGU - NTL 29

2. Stated period (renewable)

1 year (ending February 2009). 3. Payment


4. Contract Model Focus in SLA for the total operation, without specific equipages requirements neither previous permission for the ship be used in other activities, instead of being dedicated - standby during the period between repairs. Evaluation of Phase III There are 3 main points in this phase: a new boat, since occurred rescission of the contract with the previous ship; the increase of events incidence and the outsourcing of the on board inspections. It was necessary a ship with the characteristics that fullfiled the service requirements. The characteristics were: medium size ship (about 50 m or 164 ft), with a deck area enough for the equipment used in the operations, able to carry out adequate maneuvers of positioning and appropriate number of rooms for technicians, Embratel inspectors, crew, and deck operators, in a total of 40 people. Once found, the ship had to be adapted in the bow and installation of ramp for the



cable handling, adjustments in the deck for equipments installations and increment of software for maneuvers improvement. As the ship was very old (builted in 1958 and reconstructed in 1978) malfunctions have occurred in the operations carried out in this phase. So the contracted company still had some work to do for the adequate adjustment of the ship. All the operations of this phase were carried out with anchorage.

In this phase, 10 repair operations were carried out. Two activities are the causes of 9 repairs: fishing activities (7) and theft (2). In the tenth event the cause was not identified. (Table 6) Embratel also decided, in this phase, to outsource the inspections on board during the operations, using people that were trained and guided by the Embratel team.

Table 6 - Phase III - Events

Cause System Events Laid cable

Buried cable

Anchorage Fishing Theft No

Identified


3 0 3 0 3 0 0


4.4. Work phases main data

A complete view of all phases is presented at Table 7.

Table 7 - All phases - Events

System Events Mean Depht

(m)

Distance to the Coast (Km)

Mean Time to Repair

since repair notification

(days)

Mean Time to Repair

since departure (days)

Mean Time to Repair

since on site (days)

Rio ‐ São Mateus 9 37 13 12 8 6 Porto Seguro ‐ Natal 16 35 12 15 10 5 Rio ‐ São Paulo 13 50 21 8 6 5 Total 38 41 15 12 8 5

5. Comparing dedicated ship versus ACMA

Comparisons between the ACMA maintenance and the results obtained with a dedicated ship always have resulted on disadvantages for ACMA in “response time” and “running costs” items. Throughout the years, the ship’s bases and the spare’s deposits had been located in Baltimore, Bermuda, Brest, Curacao, Montevideo and Vigo, all very distant from the national system, when compared with a

dedicated ship based on Niteroi - Rio de Janeiro - Brazil. During the period 2001 / 2003, ACMA had a base in Recife - Pernambuco - Brazil. However, this localization, despite being in the Brazilian coast, still was not competible when compared with Niteroi. 6. Conclusions

• In installations with the same physical characteristics, the use of ROV could be, after analysis, eliminated.

• The main risk factors to the integrity of the cables had been fishing



activities (63%), ship’s anchorage (24%) and theft (5%). The causes of 8% of the incidents were not identified.

• To reduce the main risks of cables damages, contacts were established to exchange information about crossing and neighborhoods from others installations and to inform potential threatens about the position of Embratel cables.

• Eventual submarine work was done with divers, in the average depth where the work was realized (41 m or 134 ft).

• The cable protection by burial above 3 ft (1 m) of depth, through these years, did not prove itself to be 100% safe from the ship’s anchorage.

• The mean time to recover the cable (5 days), since the arrival of the ship to the site, despite eventually influenced by adverse conditions worst than

Beaufort 5, after the 3 phases, is still the same.

• In many cases the distance from the event to the coast is visual, showing that small boats without any additional resources (nautical charts, GPS, fish-finders, VHF radios, etc.) have easy access to the point.

• After 13 years and 38 repairs accomplished, Embratel got enough know how to continue performing the services with the quality required, despite adjustments and restrictions for which the company and the market are facing.

SUBMARINE CABLE MAINTENANCE DEDICATED SHIP – A … · Jorge de Souza Santos, Gilvan Jordão de...

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