Category Archives: Boilers

Boiler Survey on Ships

All boilers, economizers, steam receivers, steam heated steam generators, thermal oil and hot water units intended for essential services, together with boilers used exclusively for non-essential services having a working pressure exceeding 0.35 MPa and a heating surface exceeding 4.5 m2 are to be surveyed internally. There is to be a minimum of two internal examinations during each 5 Special Survey cycle. The interval between any two such examinations is not to exceed 36 months, except in exceptional circumstances. A general external examination is to be carried out at the time of the Annual Survey.

An external survey of boilers including tests of safety and protective devices, and tests of safety valves using their relieving gear, is to be carried out annually within the range dates of the Annual Survey of the ship. For exhaust gas heated economizers, the safety valves are to be tested by the Chief Engineer at sea within the range dates of the Annual Survey. This test is to be recorded in the log book and reviewed by the attending Surveyor prior to crediting the Annual Survey.

General Requirements (Boilers)

The survey of auxiliary boilers include ancillary equipment which, together with the controls, should subsequently be examined under working conditions and the correct adjustment of any safety devices to be verified.

  • A thorough external examination of boilers is to be undertaken. It is to be verified that boiler supports, chocks, rolling stays, uptakes and the funnel base are in satisfactory condition.
  • Thorough examination of each boiler, together with its superheater, superheat control, air heater and economiser, if fitted. If a boiler has not been sufficiently cleaned to allow a proper examination of pressure parts, the survey cannot be regarded as complete until this has been done.
  • Where the construction of a boiler does not allow direct visual internal examination of the shell, drums or headers, the attending Surveyor(s) are to be satisfied that the boiler is in a safe working condition by resorting to remote viewing instruments, Ultrasonic Testing (UT), or hydraulic testing to determine a safe working pressure.
  • Longitudinal stays attached to end plates by external and internal welds should be examined at the inner welds for possible cracking. All such stays should be drilled at the ends with ‘tell-tale’ holes 5 mm diameter and of sufficient depth to penetrate the center of the stay beyond the inner weld.
  • Every effort is to be made to complete the survey prior to departure. If, for any reason, the survey is not completed, the definite intentions of the Owner/Operator regarding completion are to be ascertained.
  • If a later date, more than two months after the date on which the internal examination was held, is required in cases where a ship remains in port without the appliance being placed under steam, a further internal survey is to be carried out.
  • Rolling stays, expansion/sliding feet arrangements and freedom of pins and holding down bolts are to be specially examined in way of attachments to the shell or casings and freedom of pins is to be verified.

General Requirements (Exhaust Gas Economizer)

  • If an exhaust gas economiser has not been sufficiently cleaned to allow a proper examination of pressure parts, the survey cannot be regarded as complete until this has been done.
  • Where the construction of an exhaust gas economiser does not allow direct visual internal examination of the headers, the attending Surveyor(s) are to be satisfied that the exhaust gas economiser is in a sate working condition by resorting to remote viewing instruments, Ultrasonic Testing (UT), or hydraulic testing to determine a safe working pressure.
  • The mountings (including all valves, fittings, burner units, drains and filling valves) are to be opened up for internal examination and rectification as necessary. The attending Surveyor(s) are to ensure that all mountings are securely attached and are to have insulation cut away where this prevents full examination of studs and nuts. Stub piece welds are to be examined in way of attachment to shell, shell plating in way of nozzles penetrating the shell (feed, etc.) and pads attached to the shell should be carefully examined for cracks emanating from the welds.
  • It is important that all pressure gauge connections should be free from obstructions and their shut-off fittings clearly and correctly marked to indicate when they are in the open position.
  • A thorough external examination of exhaust gas economisers should be undertaken. It should be verified that exhaust gas economiser supports, rolling stays and uptakes are in satisfactory condition. Rolling stays, expansion/sliding feet arrangements and freedom of pins and holding down bolts are to be specially examined in way of attachments to the shell or casings and freedom of pins is to be verified.

General Requirements (Safety Valves)

  • Safety valves are to be adjusted under steam to not more than 103 per cent of the approved design pressure shown in the Register Book and the Survey Preparation Package (SPP). In all cases, a record of the pressure to which the safety valves have been set should be left on board.
  • Where more than one safety valve used, the other(s) are to be gagged (prevented from opening) whilst the safety valve is tested. On completion this role is to be reversed so that in turn, all valves have been tested.
  • Verification of the calibration of the boiler pressure gauges
  • When surveying Main Boilers, Auxiliary Boilers, Exhaust Gas Boilers, Economisers or any steam plant, examination of the drain lines fitted to the safety valves to ensure they are independent, clear, unblocked and in accordance with the appropriate Rules and Regulations.

General Requirements (Alarms)

  • Survey of alarms, controls and safeguards lights during periodical surveys is a requirement of the appropriate Rules and Regulations. The purpose of this survey is to ensure that the alarms, controls or safeguards remains functional in service.
  • The survey of attended machinery space alarms, controls and safeguards required for vessels/installations assigned the LMC (Lloyd’s Machinery Certificate) notation are to be carried out in conjunction with the associated machinery item at the due date.
  • Records of changes to the hardware and software used for control and monitoring systems for propelling and essential auxiliary machinery since the original issue (and their identification) are to be reviewed.
  • Satisfactory operation of the alarms, controls and safeguards is to be verified.

An important part of a boiler survey is examination when at operating conditions and will include:

  1. Establishing that water level indicators are operating correctly by utilising a methodical blowdown sequence.
  2. Testing all safety and alarm equipment.
  3. Observation of boiler starting sequences and firing.

A general examination of the associated oil fuel system including fuel tank valves, pipes, deck control gear are also to be carried out.

General Requirements (Level Devices, Alarms and Fuel Cut Off Tests)

Examination when at operating conditions and will include:

  • Verification of the calibration of the boiler pressure gauges. Where the calibration cannot be readily verified, a written statement is to be obtained from the Master/Chief Engineer confirming that the gauges have been calibrated. Alternatively, consideration may be given to a second gauge for verification of the primary gauge.
  • Testing all safety and alarm equipment & observation of boiler starting sequences and firing.
  • A general examination of the associated oil fuel system including fuel tank valves, pipes, deck control gear are also to be carried out.

General Requirements (Internal examination including fit of doors)

  • Internal Examination of Boiler
  • The joints of manhole, mudhole or handhole doors are to be examined and to ensure that the jointing faces are in good condition and that the clearance at the spigot does not exceed 1.5 mm at any place.

General requirements (valves and mounting except steam stop valves)

  • The mountings (including all valves, fittings, burner units, drains and filling valves) are to be opened up for internal examination and rectification as necessary. Verification of all mountings are securely attached and are to have insulation cut away where this prevents full examination of studs and nuts. Stub piece welds are to be examined in way of attachment to shell.
  • Shell plating in way of nozzles penetrating the shell (feed, gauge glasses, etc.) and pads attached to the shell are to be carefully examined for cracks whose origin may stem from the welds.
  • The welded connections of stub pipes to integral steam piping, particularly in way of superheater safety valve branches, are to be specially examined for cracks/fractures using Magnetic Testing (MT) where considered necessary.
  • Pressure parts operating at high temperatures, such as superheater outlet headers and manifolds, may be subject to creep damage which can result in failure. In cases of such pressure parts which are not heated by hot gases, the highest metal temperature occurs at the internal surfaces where cracking can commence. These cracks are usually not discovered until the full thickness has been penetrated.
  • It is important that all water gauges and pressure gauge connections are to be free from obstructions and their shut-off fittings clearly and correctly marked to indicate when they are in the open position. High and low water level alarm fittings and also feed water regulators are to be examined.
  • It is important that all content gauges and pressure gauge connections should be free from obstructions and their shut-off fittings clearly and correctly marked to indicate when they are in the open position. High and low content level alarm fittings and also feed content regulators should be examined.

Boiler examination at operating conditions and will include:

  • Verification of the calibration of the boiler pressure gauges. Where the calibration cannot be readily verified, a written statement is to be obtained from the Master/Chief Engineer confirming that the gauges have been calibrated. Alternatively, consideration may be given to a second gauge for verification of the primary gauge.
  • Establishing that water level indicators are operating correctly by utilising a methodical blowdown sequence.
  • Comparison of bench tested valves previously set under workshop conditions to respective pressures as set at sea.

General requirements (Steam Stop Valves)

  • The mountings (including all valves, fittings, burner units, drains and filling valves) are to be opened up for internal examination and rectification as necessary. The attending Surveyor(s) are to ensure that all mountings are securely attached and are to have insulation cut away where this prevents full examination of studs and nuts. Stub piece welds are to be examined in way of attachment to shell.
  • Shell plating in way of nozzles penetrating the shell (feed, gauge glasses, etc.) and pads attached to the shell are to be carefully examined for cracks whose origin may stem from the welds.
  • The welded connections of stub pipes to integral steam piping, particularly in way of superheater safety valve branches, are to be specially examined for cracks/fractures using Magnetic Testing (MT) where considered necessary.
  • Pressure parts operating at high temperatures, such as superheater outlet headers and manifolds, may be subject to creep damage which can result in failure. In cases of such pressure parts which are not heated by hot gases, the highest metal temperature occurs at the internal surfaces where cracking can commence. These cracks are usually not discovered until the full thickness has been penetrated.
  • It is important that all water gauges and pressure gauge connections are to be free from obstructions and their shut-off fittings clearly and correctly marked to indicate when they are in the open position. High and low water level alarm fittings and also feed water regulators are to be examined.
  • It is important that all content gauges and pressure gauge connections should be free from obstructions and their shut-off fittings clearly and correctly marked to indicate when they are in the open position. High and low content level alarm fittings and also feed content regulators should be examined.

Reference: Rules and Regulations from Lloyd’s Register of Shipping

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