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Section 2 Survey during Construction
201. Survey during Construction
For ROV's systems requiring survey during
Construction, the construction, materials, equipment,
scantlings, workmanship and performance are to be examined in detail in order to ascertain that
they meet the appropriate requirements of the
Rules.
202. approval of plans
For ROV's systems requiring survey during Construction, the plans and documents showing the de- tails of the construction, materials, scantlings and particulars of the hull and equipment are to be submitted in accordance with as provided separately. The same applies also to the case of any sub- sequent modifications to the approved drawings or documents.
203. Workmanship
For classification survey of ROV's systems, the materials, workmanship, arrangements and perform- ances are to be surveyed under the supervision of the Society's Surveyor from the commencement of the work until the completion of the ROV's. Any item found not to be in accordance with the Rules or approved plans, or any material, workmanship, arrangement and performance found to be unsatisfactory are to be rectified.
204. Tests and Trials
1. General
(1) ROV's and their back-up systems undergo constructional and acceptance tests in the manufactur- ing works, Wherever applicable, all the tests and trials prescribed are to be performed and documented.
(2) All welding parts should be inspected with NDT (non-destructive test) as appropriately.
(3) All materials used for ROV's should be examined and conformed by the Society and the test reports shall be submitted.
2. Total system
On completion, the ROV together with its necessary back-up system, e.g. the control station, power supply and launch/recovery facilities, is to be subjected to a functional and acceptance test which shall include at least the following elements :
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(1) assembly inspection (except where this has already been carried out during supervision of con- struction),
(2) verification of weight and buoyancy,
(3) testing of all safety devices,
(4) functional test of diving and trimming system,
(5) functional test of mechanical, electrical and optical equipment including the holding and working devices,
(6) underwater trial run,
(7) verification of all important measuring instruments,
(8) high-voltage and insulation testing of electrical equipment.
3. Supporting structure
A check is to be carried out on the pressure equalization of those parts of the supporting structure which are not resistant to pressure. When necessary, welding parts are to be inspected by NDT(non- destructive test)
4. Pressure vessels
(1) A hydraulic pressure test is to be performed before the vessels are insulated or painted. This shall nor cause leakage or any permanent deformation of the walls.
(2) The test pressure for vessels is generally equal to 1.5 times the maximum working pressure when the pressure is applied internally.
(3) Vessels liable to be subjected to an external pressure corresponding to the maximum permissible operating depth of the ROV are to undergo an external-pressure test. The test pressure must be
equivalent to at least 1.3 times the nominal diving depth.
5. Piping, valves, fittings, hoses and umbilicals
(1) After installation, all pipes are to be subjected to a pressure and tightness test at 1.5 times the design pressure.
(2) Proof is to be submitted to the Society of the burning pressure of each type of hose line. For
liquids, hose line must be able to withstand at least 4 times and, for gases, at least 5 times the maximum working pressure.
(3) Each nose line is to e subjected to a hydraulic pressure test at least the maximum working pressure.
(4) Where hose lines are subjected to an externals excess pressure, proof is required that 1.5 times the difference between the internal and external pressure can be tolerated without failure.
(5) Umbilicals are to undergo a tightness test in which all the hose lines are simultaneously sub- jected to their respective maximum working pressure and measurements are performed on the electrical lines to verify that the insulation values specified by the manufacturer are maintained at a test voltage equal to or greater than 500 V. The effectiveness of the strain-relief device is also to be tested.
(6) Where the tether forms an internal part of the umbilical, the mechanical properties are to be tested.
6. Pumps
On completion, pumps are to be subjected by the manufacturer to a tightness test at maximum working pressure and to a performance test.
7. Controls for depth, trimming and positive/negative buoyancy systems
(1) Trimming, bilge and ballast systems are to undergo a functional test.
(2) The diving tank venting system and control elements(where present) are to be subjected to a functional test.
8. Propulsion and maneuvering equipment
Operation of the propulsion and maneuvering equipment is to be verified in the course of the un- derwater trial run.
9. Electrical equipment
(1) Electrical machines and switchboards including operating and control station, and automation, alarm and safety equipment are to be inspected and tested in the manufacturer's work.
(2) All electrical systems and equipment are to be inspected and tested prior to commissioning of
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the ROV.
(3) The settings and thresholds of the electrical protective devices are to be checked, and in addi- tion the ROV electrical systems are to be subjected to a high voltage and insulation test at a test voltage equal to or greater than 500 V.
(4) After the connectors have been fitted, each manufactured length of power-supply cable is to be subjected to a pressure test at 1.3 times the maximum operating pressure.
10. Clamping and positioning devices
Clamping and positioning devices are to undergo a functional test comprising at least the following elements.
(1) the specified clamping power of the clamping device.
(2) the limits of power and movement of clamping devices and the alignment of the ROVs
(3) simulated power failure
(4) maintenance of course and depth with automatic positioning
11. Working appliances
As a minimum requirements, working appliances are to be tested with regard to :
(1) capacity to fulfil their specified function
(2) control and monitoring
(3) operation of safety devices
12. Automation, navigation and locating equipment
(1) Indicators and monitors are to be checked for ergonomic arrangement, accuracy of readings and limit settings.
(2) Automatic monitoring systems are to be checked for fauless operation under service conditions.
13. Garage
(1) Launching and recovery of the garage together with the ROV is tro be verified a functional test.
(2) Exit and entry of the ROV to and from the garage is to be tested under water (functional test
of all the garage equipment)
(3) The garage lifting attachment is to be tested at twice the working load.
14. ROVs control Stations
ROVs control stations are to comply with Pt 9, Ch 7 of Rules for the Classification of Steel Ships.
15. Launching and recovery system
Launching and recovery system are to comply with Pt 9, Ch 7, 607. 12. of Rules for the Classification of Steel Ships.
205. Markings
1. All important valves, fittings, operating elements, indicators and alarms are to be provided with a permanent marking resistant to seawater.
2. All pressure vessels and pressurized gas containers are to be prominently and permanently marked with the following details :
(1) manufacturer or supplier
(2) maker's number
(3) type of manufacture
(4) maximum working pressure (bar)
(5) test pressure
(6) capacity (liter or À Ė)
(7) empty weight (or pressurized gas container)
(8) type test mark on type tested pressure vessels
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