Section 2 Testing During Construction

201. Tank, bulkhead and fitting

1. General

Following parts are to be tested and proven tight. Refer to Table 1.2.1 for specific test requirements. Close visual examination combined with NDT may be accepted in certain areas where specially approved, as an alternative to hose testing.

(1) Hatch, watertight passageway

(2) Joint and penetration part of pipe

(3) Tank & watertight bulkhead or flat

2. Tank testing

A tank testing procedure is to be submitted for review and approval.

Table 1.2.1 lists the types of tests which normally apply. Where permitted in Table 1.2.1, air testing or combined air hydrostatic testing by an approved procedure may be accepted unless the specified test is deemed necessary by the Surveyor. Where air testing is adopted all boundary welds, erection joint and penetrations including pipe connections are to be examined under the ap- proved test procedure with a suitable leak indicator solution prior to the application of special coatings. Are test pressure differential should normally be 0.15 × 105 (0.15 ). Prior to in- spection, it is recommended that the air pressure in the tank is raised to 0.20 × 105 (0.2

) and kept at the level for about 1 hour to reach a stabilized state, with a minium number of per- sonnel in the vicinity of the tank, and then lowered to the test pressure. Means are to be provided to prevent accidental over pressuring of tanks during testing. Air pressure drop testing, i.e., check- ing for leaks by monitoring drop in pressures, is not an acceptable substitute for required hydro- static or air/soap testing.

3. Hydorstatic testing

Tank designs and configurations of a non-conventional nature may be required to be hydrostatically tested. Tanks or unit which will be submitted in service and designed to withstand external hydro- static loading will require hydrostatic testing unless otherwise approved. When hydrostatic testing

applies, tests may be carried out before plied before hydrostatic testing provided

or after the buoy is launched. Special coatings maybe ap- all welded joint and penetrations are visually examined to

Ch 1

the satisfaction of the Surveyor before special coating is applied.

4. Hose testing

Hose testing is to be carried out under simultaneous inspection of both sides of the joint. The pressure in the hose is not to be less than 2.0 × 105 (2.0 ) is to be applied at a maximum distance of 1.5 . The mozzle diameter is not to be less than 12 .

5. Mooring system tests

Each anchor leg is to be examined together with attachments and securing devices provided for connection to the buoy. Proper fitting of components, connectors and securing devices is to be demonstrated.

(1) Anchor legs

Anchor legs consist of mooring chains, connectors such as shackles, connecting links, and other fittings. Each mooring leg is to be pull tested upon installation in accordance with an approved procedure in the presence of a Surveyor. The pull test is to be in accordance with Ch 3, Sec 4.

(2) Mooring between vessel and SPM

Mooring structure

between vessel and SPM which may include either flexible hawsers or rigid mooring (rig arms and yokes) are to be examined. The hawsers are to be examined and veri-

fied for size, materials, specifications, and type of the approved design. Proper fitting and secur-

ing of all components is to be verified. NDT of the rigid mooring structure to the SPM buoy is to be carried out to the satisfaction of the attending Surveyor.

(3) Tower mooring

Tower mooring designed as a fixed structure, usually made of tubular members, may be used in place of buoyant structure and mooring lines.

(4) Pile and anchor

Where piles or gravity boxes are used as anchoring system of an SPM system NDT is to be performed. Surveys regarding the manufacturing and testing of anchors are to be in accordance with Pt 4 of "Rules for Classification of Steel Ships".

6. Cargo transfer system

The entire cargo transfer system including hoses/flexible risers, swivels, and valves is to be hydro-

statically tested after installation to the design pressure. Refer to Table 1.2.1 and specific requirements.

Table 1.2.2 for

Table 1.2.1 Initial tank & Bulkheads tightness test requirements

Table 1.2.2 Survey and Testing Requirements During Construction

7. Control and safety system

All control and safety equipment is to be examined and proven service. Refer to Table 1.2.2 for specific requirements.

8. Hoses, flexible risers

(1) Hose/Flexible riser testing

Refer to Ch 4, Sec 1 of these Guidances.

(2) Buoyancy tank pressure test

Ch 1

to be adequate for the intended

Any buoyancy tank intended to be pressurized to equalize the external pressure will be tested to a pressure 1.5 times the maximum allowable working pressure.