Section 1 General

1.1.1 The requirements of this Chapter are to be complied with in cases where Lloyd’s Register (LR) is requested to issue a Register of Ship’s Lifting Appliances and Cargo Handling Gear for derrick systems.

1.1.2 Masts, derrick posts and similar supporting structures for cargo handling devices are classification items and are to comply with the relevant Sections of this Chapter whether or not LR is also requested to issue the Register of Ship’s Cargo Gear and Lifting Appliances. See Pt 3, Ch 9, 6 Lifting appliances and support arrangements of the Rules and Regulations for the Classification of Ships (hereinafter referred to as the Rules for Ships).

1.1.3 The requirements given in this Chapter are applicable to the following types of derrick system:

• Swinging derricks.
• Union purchase rigs.
• Derrick cranes (although Chapter 4 may be applicable to certain types of derrick crane as defined in Ch 2, 5.1 General 5.1.1).

Derricks of special design will be considered on the general basis of these requirements.

1.1.4 Typical arrangements of swinging derrick systems are shown in Figure 2.1.1 Typical rigs for light loads and Figure 2.1.2 Typical rig for heavy loads. These arrangements are given for illustration only and to indicate the nomenclature used in the systems.

Figure 2.1.1 Typical rigs for light loads

Figure 2.1.2 Typical rig for heavy loads

1.2.1 Alternative arrangements or fittings which are considered to be equivalent to those specified in this Chapter will be accepted.

1.2.2 International or National Standards will be considered as an alternative basis for approval, provided LR is satisfied that these are at least equivalent to the criteria specified in this Chapter.

1.3.1 Where the derrick system incorporates novel features, LR may require additional calculations or model testing to be carried out.

1.3.2 Direct calculations using computer programs may be used as an alternative to the calculation procedures of this Chapter. Where programs other than those available from LR are employed, the assumptions made and the calculation procedures used are to be submitted for approval. Where calculations using these procedures are made, the results are to be included with the plans submitted for approval.

1.4.1 The plans and information listed in Ch 1, 3 Plans and information to be submitted are to be submitted for approval.

1.4.2 It is recommended that the information be presented in the form of a Cargo Gear Particulars Book and that a copy be placed on board the ship. See Ch 13, 2.1 Initial Surveys.

1.4.3 Plans of masts and derrick posts are required to be approved for classification purposes, and these plans, together with a Rigging Plan and diagrams of forces, are to be submitted in all cases, whether or not LR’s Register of Ship’s Lifting Appliances and Cargo Handling Gear is to be issued.

1.5.1 Derrick systems are to be constructed of steel which complies with the requirements of Ch 1, 1.6 Materials and fabrication and Ch 11 Materials and Fabrication. Proposals to use materials other than steel will be specially considered. The fabrication is to be in compliance with Ch 11, 2 Fabrication of classed lifting appliances or Ch 11, 3 Fabrication of certified lifting appliances.

1.5.2 Steel for masts, derrick posts and associated items included in the classification of the hull is to comply with the requirements of the Rules for the Manufacture, Testing and Certification of Materials, July 2022. The steel is to comply with the Charpy V-notch impact test requirements given in Ch 11, 1.2 General material requirements 1.2.2, with the operating temperature chosen as being the lesser of either that from an assigned winterisation notation or the lowest temperature of operation for the derrick system (see Ch 11, 1.2 General material requirements 1.2.4).

1.5.3 Steel for derrick booms and associated fittings is to comply with LR’s requirements as in Ch 2, 1.5 Materials 1.5.2 or with a recognised National or International Standard, see Ch 1, 1.6 Materials and fabrication.

1.5.4 Steel castings and forgings are to be normalised or otherwise heat-treated at a temperature and according to a method appropriate to the material and size of the item.

1.5.5 Cast, forged and fabricated items, are to be so designed and constructed as to minimise stress concentrations. Fabricated items are to be designed to ensure good penetration of welds and adequate accessibility for non-destructive examination as necessary.

1.5.6 The required documentation for materials used for the construction of classed and certified derrick systems is defined in Ch 11, 4 Material documentation for certified and classed lifting appliances.

1.6.1 The nomenclature adopted for the principal items comprising the derrick system is shown in Figure 2.1.1 Typical rigs for light loads and Figure 2.1.2 Typical rig for heavy loads.

1.6.2 The following symbols are used throughout this Chapter:

1.6.3 Remaining symbols are defined as they occur.