Section 1 General requirements

1.1.1 The requirements of this Chapter are applicable to fusion welded pressure vessels and their mountings and fittings, for the following uses:

1. Production or storage of steam.

2. Heating of pressurised hot water above 120°C.

3. Heating of pressurised thermal liquid.

Seamless pressure vessels are to be manufactured and tested in accordance with the requirements of Ch 5 Steel Forgings of the Rules for the Manufacture, Testing and Certification of Materials.

1.1.2 The scantlings of coil type heaters with pumped circulation, which are fired or heated by exhaust gas are to comply with the appropriate requirements of Pt 5, Ch 10 Steam Raising Plant and Associated Pressure Vessels the Rules and Regulations for the Classification of Ships (hereinafter referred to as the Rules for Ships).

1.1.3 Where exhaust gas emissions abatement equipment is fitted to steam raising plant, it is to meet the requirements of Pt 5, Ch 24 Emissions Abatement Plant for Combustion Machinery of the Rules for Ships.

1.2.1 Plans of boilers, having working pressures exceeding 3,4 bar and having heating surfaces greater than 4,65 m² are to be submitted in triplicate for approval before construction is commenced.

1.2.2 These plans should give full constructional features of fusion welded pressure vessels and dimensional details of the weld preparation for longitudinal and circumferential seams and attachments, together with particulars of the welding consumables and of the mechanical properties of the materials.

1.2.3 Boiler Manufacturers are referred to in Pt 5, Ch 10 Steam Raising Plant and Associated Pressure Vessels of the Rules for Ships,, which contain detailed requirements for the materials, the manufacture and testing of boilers.