CEN/TC 269/WG 3 - Equipment

This part of this European Standard specifies the essential requirements for equipment and protective devices for water-tube boiler plant as defined in EN 12952-1, to ensure the boiler operates safely within the allowable limits (pressure, temperature, etc.).
NOTE 1   Additional requirements specially needed for boilers without manual intervention are specified in Clause 7.
NOTE 2   Requirements for equipment for chemical recovery boilers are given in Annex A.

This part of this European Standard specifies the minimum requirements for safety related equipment for shell boilers as defined in EN 12953-1, to ensure the boiler operates within the allowable limits (pressure, temperature, etc.) and if the limits are exceeded the energy supply shall be interrupted and locked out without manual (human) intervention at the boiler.
NOTE 1   The maximum time of operation without manual (human) intervention should be defined for each boiler system.
NOTE 2   Annex C (informative) gives recommendations of operation and testing of the boiler system with a maximum time of operation without manual (human) intervention of 72 hours.

This European Standard specifies requirements for limiters (or limiting devices) which are incorporated into safety systems for shell boilers as defined in EN 12953-1.
A limiter (or limiting device) can be either:
-   a safety accessory as defined in the Pressure Equipment Directive, Article 1, clause 2.1.3, and needs to include the safety logic and final actuator, or
-   one element of a safety system, for example, a self-monitoring water level sensor used as part of a safety accessory as defined in the Pressure Equipment Directive, Article 1, clause 2.1.3. The overall boiler protection function needs to be provided in association with additional safety logic (where appropriate) and a final actuator.
The design requirements and examination of functional capability for the limiters are covered in this European Standard.
For an explanation of the extent of the limiter (or limiting device) see Figure A.1.

This European Standard specifies requirements for limiters (or limiting devices) which are incorporated into safety systems for water-tube boilers as defined in EN 12952-1.
A limiter (or limiting device) can be either:
-   a safety accessory as defined in the Pressure Equipment Directive, Article 1, clause 2.1.3, and needs to include the safety logic and final actuator, or
-   one element of a safety system, for example, a self-monitoring water level sensor used as part of a safety accessory as defined in the Pressure Equipment Directive, Article 1, clause 2.1.3. The overall boiler protection function shall be provided in association with additional safety logic (where appropriate) and a final actuator.
The design requirements and examination of functional capability for the limiters are covered in this European Standard.
For an explanation of the extent of the limiter (or limiting device) see Figure A.1.

This draft European Standard covers the safety requirements regarding the storage and use of:
-   liquefied pressurized ammonia for steam boiler plants;
-   liquid ammonia water solution for the reduction of NOx in the flue gas from boiler plants.
Annex A summarizes the operational aspects.

This European Standard covers direct-fired steam and hot water generators, including the auxiliaries. For the purposes of this standard, steam and hot water generators are vessels and pipework systems in which:
¾ steam at a pressure higher than atmospheric pressure is generated for use external to the system;
¾ water is heated to a temperature higher than the saturation temperature at atmospheric pressure for use external to the system.
A steam generator normally consists of the flue gas-heated evaporator, the superheater, the reheater, the feedwater heater, the air heater, the fuel heater, if any, and the fuel burning equipment.
The term 'direct-fired' relates to equipment by means of which the chemical heat in the fuel of known composition is converted to sensible heat. Such equipment can involve stoker firing, fluidized-bed combustion or burner systems.
The auxiliaries include the fuel feeders, the pulverizer, the FD (forced draught) fan, the ID (induced draught) fan, the facilities for removal of the refuse (combustion residues), the steam air heater, the main air heater, the fuel heater, if any, and the dust collector.

This part of this European Standard specifies the requirements for internal or external grate firing systems commencing at the fuel bunkers and ending at the ash extraction plant. For combination of various firing systems, the individual requirements of each system also apply.
If several fuels are burnt simultaneously or if a fuel quality varies considerably (e.g. moisture content), additional safety measures can be necessary, especially with respect to limitation of the fuel flow into the firing system and ensuring proper air supply to the individual fuels.

This Part of this European Standard specifies a concise procedure for conducting thermal performance tests, using the indirect (losses) procedure for boilers for steam or hot water. Test results are based on either the gross or net calorific value of the fuel.
This concise procedure provides a convenient means for assessing boilers which thermodynamically simple, i.e. having a single major source of heat input and a simple circuit for water, steam or high temperature heat transfer fluid.
NOTE 1   The use of the direct method is not advocated, because the estimated measuring error is three to four times greater than with the indirect method.
NOTE 2   An acceptance test may be required:
a) after the commissioning of new plant or after the recommissioning of modified plant in order to verify compliance with a specification or contractual obligation;
b) whenever the user wishes to determine the current performance of the plant either on a route basis or due to change of load or other operating conditions or when a change of fuel or a modification to the plant is being considered;
c) whenever the user wishes to check combustion conditions.
Regular tests in accordance with this European Standard will enable boiler plant to be monitored in normal operation for opti-mum efficiency in the interests of fuel conservation.
This procedure does not cover condensing boilers. The application of boilers, where heat is extracted from waste gases is specified in annex B.

This European Standard applies to the design of equipment for boiler plants to reduce air pollutants in the flue gases.
NOTE   The effects of explosion are not considered in this Part of the is European Standard.

This part of the European Standard applies to all shell boilers as defined in prEN 12953-1 which are heated by combustion of one or more fuels or by hot gases for the generation of steam and/or hot water. This European Standard applies to those components between the feedwater inlet and the steam outlet of the steam generator. The quality of the steam produced is outside the scope of this standard.

This Part of this European Standard applies to all water-tube boilers as defined in EN 12952-1 which are heated by combustion of one or more fuels or by hot gases for the generation of steam and/or hot water.
This Part of this European Standard applies to those components between the feedwater inlet and the steam outlet of the steam generator. The quality of the steam produced is outside the scope of this standard.
This Part of this European Standard aims to ensure that the boiler is able to be operated to minimize risk to personnel, the boiler and associated plant components located near it.
NOTE   This European Standard does not aim to achieve optimum economic operation. For certain purposes, it will be more appropriate to optimize the chemical characteristics in order to:
- increase the thermal efficiency;
- increase the availability and reliability of the plant;
- increase steam purity;
- reduce the maintenance costs - repair, chemical cleaning, etc.
This Part of this European Standard sets out minimum requirements for the specific types of water to reduce the risk of corrosion, sludge precipitation or formation of deposits which may lead to any damage or other operating problems.
NOTE   This Part of this European Standard has been prepared on the assumption that the user of this European Standard possesses a sufficient knowledge of the construction and operation of the boiler as well as an adequate appreciation of water and steam chemistry.

These requirements apply to oil and gas firing systems of steam and hot water generators. For multifuel firing systems using separate or combined burners these requirements shall apply to the oil and/or gas firing part involved. Where several fuels are burnt simultaneously, improved safety measures may be necessary, especially in respect to limitation of heat input into the firing system and proper air supply to the individual fuels.

This Part of this European Standard specifies the requirements for safeguards against excessive pressure in shell boilers
as defined in EN 12953-1.

These requirements apply to atmosperic fluidized-bed and grate firing systems. This system commence at the fuel bunkers and at the ash extractions plant. For combination of various firing systems, the individual requirements of each system shall also apply, especially those included in prEN 12952-8 and prEN 12952-9. If several fuels are burnt simultaneously or if a fuel quality varies considerably (e.g. moisture content), additional safety measures may be necessary, especially with respect to limitation of the fuel flow into the firing system and ensuring proper air supply to the individual fuels.

1.1 Firing systems: These requirements apply to pulverized fuel firing systems of steam and hot water generators (boilers) and commence at the filling equipment for the boiler bunkers or for the pulverized fuel storage system and end at the ash extraction plant. For multifuel firing systems using separate or combined burners these requirements shall apply to the pulverized fuel firing part involved. For other fuels or firing systems used in combination other requirements shall apply e.g. prEN 12952-8.

1. Firing systems: These requirements apply to oil and gas firing systems of steam and hot water generators. For multifuel firing systems using separate or combined burners these requirements shall apply to the oil and/or gas firing part involved. Where several fuels are burnt simultaneously, improved safety measures may be necessary, especially in respect to limitation of heat input into the firing system and proper air supply to the individual fuels. 2. Fuels (...) 3. Operation (...)

This European Standard specifies the requirements for safeguards against excessive pressure in water-tube boilers as defined in prEN 12952-1.

This part of the European Standard defines the requirements for equipment for steam boilers and hot water generators as defined in EN 12952-1, wherein steam or hot water will be generated. Requirements for equipment for chemical recovery boilers are given in annex A and design examples for hot water generating systems are given in annex B.

This standard applies to shell boilers as defined in EN 12953-1. This Part of the European standard specifies rules for safety related equipment of shell boilers.