Section 7 Inspection, workmanship and testing
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Inland Waterways Ships, July 2022 - Part 3 Ship Structures (General) - Chapter 1 General - Section 7 Inspection, workmanship and testing

Section 7 Inspection, workmanship and testing

Parent topic: Chapter 1 General

7.1 Inspection

7.1.1 Adequate facilities are to be provided to enable the Surveyor to carry out a satisfactory inspection of all components during each stage of prefabrication and construction.

7.2 Workmanship

7.2.1 All workmanship is to be of good quality and in accordance with good shipbuilding practice. Any defect is to be rectified to the satisfaction of the Surveyor before the material is covered with paint, cement or other composition. The materials and welding are to be in accordance with the requirements of LR’s Rules for the Manufacture, Testing and Certification of Materials, July 2022 (hereinafter referred to as the Rules for Materials). The assembly sequence and welding sequence are to be agreed prior to construction and are to be to the satisfaction of the Surveyor. Plates which have been subjected to excessive heating while being worked are to be satisfactorily heat treated before being erected in the hull.

7.2.2  Wood sheathing on decks. Where plated decks are sheathed with wood, the sheathing is to be efficiently attached to the deck, caulked and sealed, to the satisfaction of the Surveyor.

7.2.3  Rudder and sternframe. The final boring out of the propeller boss and sternframe skeg or solepiece, and the fit-up and alignment of the rudder, pintles and axles is to be carried out after completing the major parts of the welding of the after part of the ship. Other methods will be specially considered. The contacts between conical surfaces of pintles, rudder stocks and rudder axles are to be checked before the final mounting.

7.3 Acceptance testing on completion

7.3.1  Hose testing. The items listed in Table 1.7.1 Hose testing requirements are to be carefully examined and hose tested to the satisfaction of the Surveyor.

Table 1.7.1 Hose testing requirements

Item Requirement
All ship types  
  Watertight doors, in place  
  Watertight bulkheads, flats and recesses  
  Weathertight doors and other weathertight closing appliances Pressure at least 0,2 N/mm2 (2,0 kgf/cm2) at maximum distance of 1,5 m from item under test, or equivalent
  Weathertight steel hatch covers
Oil tankers and chemical tankers  
  Pump-room bulkheads not forming tank boundaries  
  Remainder of pump-room space, see Note  

Note To be carefully examined with the vessel afloat and if found satisfactory the hose test may be dispensed with.

7.3.2  Pressure testing. The items listed in Table 1.7.2 Testing requirements are to be subjected to the appropriate test head using water; however, a proposal for a combination of pressure testing and leak testing will be considered.

Table 1.7.2 Testing requirements

Item to be tested Pressure testing requirements Leak testing requirements - air pressure
All ship types, where appropriate
Deep tanks, bunkers, peak tanks, side tanks, combined double bottom and side tanks, (including closing arrangements) 1 m head above the highest point of the tank, excluding hatchway, or to the top of the overflow, whichever is the greater, but is to be not less than 1,0ρ m above the top of the tanks where ρ is the relative density (specific gravity) of the intended cargo 0,007 N/mm2 (0,07 kgf/cm2)
Water ballast tanks As for deep tanks As for deep tanks
Cargo holds used for ballast Depending on approved height of ballast in hold As for deep tanks
Scupper and discharge pipes in way of tanks As for deep tanks As for deep tanks
Peak bulkheads not forming boundaries of tanks Peaks to be filled with water to the level of the load waterline -
Double plated rudders and nozzle - 0,01 N/mm2 (0,10 kgf/cm2), and arrangements made to ensure that no pressure in excess of 0,015 N/mm2 (0,15 kgf/cm2) can be applied
Double bottom tanks Head of water representing the maximum pressure which could be experienced in service, or to the top of the overflow, whichever is the greater 0,007 N/mm2 (0,07 kgf/cm2)
Watertight doors (passenger ships) Each door is to be tested to a head up to the bulkhead deck, either before or after fitting Not applicable
Void spaces (not accessible) - 0,007 N/mm2 (0,07 kgf/cm2)
Tankers not carrying dangerous liquids in bulk
Cargo tanks, cofferdams and cargo tanks not forming part of the ship's structure 1 m head of water above the highest point of the tank, excluding hatchway, or to top of hatchways for cofferdams, but is to be not less than 1,0ρ m above the top of the tank where ρ is the relative density (specific gravity) of the intended cargo 0,007 N/mm2 (0,07 kgf/cm2)
Item to be tested Tanker type Pressure testing requirements Leak testing requirements – Air pressure
Tankers carrying dangerous liquids in bulk, see Pt 4, Ch 6 Tankers of Types C and N
Cargo tanks and independent cargo tanks G Depending on properties of liquid Not applicable
Cargo tank hatchways and covers C and N Closed with design pressures from 10 up to and including 15 kPa Tank to be subjected to a head of water of 0,13 x (design pressure in kPa) above top tank, excluding hatchways, see Note 1 0,007 N/mm2 (0,07 kgf/cm2)
C and N Closed with design pressures greater than 15 up to and including 50 kPa Tank to be subjected to a head of water of 0,13 x (design pressure in kPa) above top tank, excluding hatchways
N Open with flame screens and N Open 1 m head of water above top of tank or 0,50 m above top of hatchway, whichever is greater
Cofferdams with hatchways G, C and N Closed, N Open with flame screens and N Open 1 m head of water above top of the cofferdam 0,007 N/mm2 (0,07 kgf/cm2)

Note 1. If the relative density (specific gravity) of the cargoes on which the scantlings of the tanks are based is in excess of 1, these test heads are to be multiplied by a factor equal to the relative density, but this factor should not be taken greater than 1,2.

Note 2. The cargo tanks and cofferdams are to be tested using water.

Note 3. In no case is the test pressure to be more than is indicated on the approved plans.

7.3.3  Leak testing. This test is carried out by applying a soapy water solution to the tank boundaries while the tank is subjected to an air pressure of 0,007 N/mm2 (0,07 kgf/cm2). It is recommended that the air pressure in the tank is raised to 0,010 N/mm2 (0,10 kgf/cm2), with a minimum number of personnel in the vicinity of the tank, and then lowered to the test pressure prior to inspection. Leak testing is normally to be carried out before a protective coating is applied. However, subject to careful inspection by the Surveyors, a complete protective coating may be applied prior to leak testing, except internally in way of welds made by processes other than automatic.

7.3.4 When a preservative coating is to be applied to the internal structure of a tank, the water testing may take place after the application of the preservative, provided that the structure is carefully examined to ensure that all welding and structural stiffening is completed prior to the application of the coating, excluding prefabrication primers. The cause of any discolouration or disturbance of the coating is to be ascertained, and any deficiencies repaired. The attachment of fittings to oiltight surfaces should be completed before tanks are tested.

7.3.5 Pressure testing may be carried out afloat where testing using water is undesirable in dry dock or on the building berth. The testing afloat is to be carried out by separately filling each tank and cofferdam to the test head. For tankers, the testing afloat is to be carried out by separately filling each tank and cofferdam to the test head given in Table 1.7.2 Testing requirements. With about half the number of tanks full, the bottom and lower side shell in the empty tanks is to be examined and the remainder of the bottom and lower side shell examined when the water is transferred to the remaining tanks. The sequence of tank testing is not to lead to unacceptable stresses being imposed upon the hull girder.

7.3.6 If, on cargo tanks of tankers, structural pressure testing has been carried out prior to the fitting of measuring devices, pipe connections and other equipment with passages through the deck or through the cargo hatch, additional leak tests are to be carried out in order to verify the tightness in way.

7.4 Trial trip and operational tests

7.4.1 The items listed in Table 1.7.3 Trial trip and operational tests are to be tested on completion of the installation or at sea trials.

Table 1.7.3 Trial trip and operational tests

Item Requirement
Sliding watertight doors To be operated under working conditions.
Windlass An anchoring test (bow and stern anchors) is to be carried out in the presence of the Surveyors.
The test should demonstrate that the windlass with brakes, etc. functions satisfactorily and that the power to raise anchor can be developed.
Steering gear, main and auxiliary To be tested under working conditions, to the satisfaction of the Surveyors.
Power operated steering gear is to be capable of moving the completely immersed rudder, whilst the ship is running ahead at maximum service speed, from 30° on either side to 30° on the other side within 15 seconds.
Bilge suctions in holds, and hand pumps in peak spaces To be tested under working conditions to the satisfaction of the Surveyors.
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