ABS海上浮式结构规范g

RULES FOR BUILDING AND CLASSING

MOBILE OFFSHORE DRILLING UNITS

2001

NOTICE NO. 1 – January 2002

The following Rule Changes are EFFECTIVE AS OF 1 JANUARY 2002.

PART 4MACHINERY AND SYSTEMS

CHAPTER 2PUMPS AND PIPING SYSTEMS

SECTION 1GENERAL

(2002)

7 Pressure

Tests

(Revise and add text as follows:)

In addition to the testing and inspection of materials, as required in Chapter 3 of the Rule Requirements for Materials and Welding – Part 2, the following tests on the fabricated piping are to be witnessed by the Surveyor after bending and the attachment of flanges.

Small bore pipes and tubes of less than 15 mm outside diameter may be exempted from the required hydrostatic tests.

7.1Fuel-oil Service System

Pressure lines are to be tested before installation to 1.5 times the design pressure of the system, but not less than 3.4 bar (3.5 kgf/cm2, 50 psi).

7.3Fuel-oil Suction and Transfer Lines

Transfer systems and fuel-oil suction lines are to be tested before installation to 3.4 bar (3.5 kgf/cm2,

50 psi).

7.5Starting-air Piping

Piping in starting-air systems is to be tested, preferably before installation, to 1.5 times the design pressure of the system.

7.7Hydraulic Power Piping

After fabrication, the hydraulic power piping system or each piping component is to be tested to 1.5 times the design pressure.

7.9All Piping

After installation all piping is to be tested under working conditions.

Where it is not possible to carry out the required hydrostatic tests for all segments of pipes and integral fittings before installation, the remaining segments, including the closing seams, may be so tested after installation. Or, where it is intended to carry out all the required hydrostatic tests after installation, such tests may be conducted in conjunction with those required by this paragraph. In both these respects, testing procedures are to be submitted to the Surveyor for acceptance.

7.11Specific Systems

The following piping systems are to be hydrostatically tested in the presence of the Surveyor

to 1.5P, but not less than 4 bar (4.1 kgf/cm2, 58 psi), after installation:

i)gas and liquid fuel systems

ii)heating coils in tanks

7.13Hydrostatic Tests of Shell Valves

All valves intended for installation on the side shell at or below the load waterline, including those at the sea chests, are to be hydrostatically tested in the presence of the Surveyor, before installation to a pressure of at least 5 bar (5.1 kgf/cm2, 72.5 psi).

7.15Pneumatic Tests in Lieu of Hydrostatic Tests

In general, a pneumatic test in lieu of a hydrostatic test is not permitted. Where it is impracticable to carry out the required hydrostatic test, a pneumatic test may be considered. In such cases, the procedure for carrying out the pneumatic test, having regard to safety of personnel, is to be submitted to the Surveyor for review.

PART 4MACHINERY AND SYSTEMS

CHAPTER 2PUMPS AND PIPING SYSTEMS

SECTION 3BILGE AND BALLAST SYSTEMS AND TANKS

13Ballasting Systems for Column-Stabilized Units

13.5Pumps

13.5.2Pump Performance (2002)

(Revise text as follows:)

At least two pumps are to be capable of effectively emptying each intact tank at maximum

normal operating draft when the unit is subject to the conditions specified in 3-3-1/1.3.2.

[Note: Loss of a pump(s) due to flooding of a pump room is to be considered in meeting this

requirement.] Each of the pumps utilized in meeting the above requirement is to have

adequate head/capacity characteristics and available net positive suction head (NPSHa) to

operate at the angles of heel and trim associated with the conditions specified in 3-3-1/1.3.2 at

a capacity of not less than 50% of the capacity required from that pump to meet the criteria of

4-2-3/13.1.

Pump data and calculations substantiating compliance with this requirement are to be

submitted. The use of submersible pumps will be subject to special consideration.