Standards Development

Scope

1.1 General

This European Standard applies to shell boilers with volumes in excess of 2 litres for the generation of steam and/or hot water at a maximum allowable pressure greater than 0,5 bar and with a temperature in excess of 110 °C.

For the purpose of this European Standard includes the following pressurized parts:

— the shell boiler as one entity of pressure equipment including all the pressure parts from the feedwater/hot water inlet (including the inlet valve) up to and including the steam/hot water outlet (including the outlet valve or, if there is no valve, the first circumferential weld or flange downstream of the shell boiler or if applicable the outlet header);

— all superheaters, economizers and interconnecting piping;

— additionally, the piping that is connected to the boiler involved in services such as draining, venting, desuperheating, etc., up to the first isolating valve or, if there is no valve, the first circumferential weld or flange downstream of the shell boiler or if applicable the outlet header/piping.

The purpose of this European Standard is to ensure that the hazards associated with the operation of shell boilers are reduced to a minimum and that adequate protection is provided to contain the hazards that still prevail when the shell boiler is put into service. This protection will be achieved by the proper application of the design, manufacturing, testing and inspection methods and techniques incorporated in the various parts of this European Standard. Where appropriate, adequate warning of residual hazards and the potential for misuse are given in the training and operating instructions and local to the equipment concerned (see EN 12953­7:2002 and EN 12953­8:2001).

It is the manufacturer's responsibility, in addition to complying with the requirements of this standard, to take into consideration special measures which could be necessary in order to achieve by manufacturing the required level of safety determined by the risk and hazard analysis.

NOTE 1 Further requirements relating to operating instructions and to the risk and hazard analysis in EN 12953­13:2012 and in CEN/TR 764­6:2012 can be taken into consideration.

NOTE 2 For safety requirements, see also Directive 2014/68/EU (PED). This European Standard specifies requirements for both directly fired and electrically heated boilers including Low Pressure Boilers (LPB, see 3.6) as well as for heat recovery boilers with a gas­side pressure not exceeding 0,5 bar of cylindrical design, constructed from carbon or carbon manganese steels by fusion welding and a design pressure not exceeding 40 bar. The boilers covered by this European Standard are intended for land use for providing steam or hot water (typical examples are shown in Figures 1 to 6).

NOTE 3 For design pressure exceeding 40 bar, EN 12953 series can be applied if no further risk and hazards are identified. For Low Pressure Boilers (LPB) less stringent requirements concerning design and calculation are acceptable. Details are defined in the respective clauses.

NOTE 4 For boilers operating at a pressure on the gas­side greater than 0,5 bar the rules of this standard equally apply. However, it is generally considered that additional design analysis, inspection and testing may be necessary.

Where a particular boiler is a combination of shell and water­tube design then the water­tube standard series EN 12952 is used in addition to this European Standard. One such example of this combination is shown in Figure 3.

1.2 Exclusions

This European standard does not apply to the following types of boilers and equipments:

a) water­tube boilers;

b) non stationary boilers, e.g. locomotive boilers;

c) thermal oil boilers; 

d) boilers where the main pressure housing is made of cast material.

e) pumps, gaskets, etc.

f) brickwork setting and insulation, etc.

NOTE Stainless steel boilers are covered by EN 14222:2021.

Purpose

EN 12953­1:2012 needs to be globally revised to be in line with the new PED Directive 2014/68/EU and for taking into account the evolution of the State of the Art in the field of shell boilers and auxiliary installations.