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     3. MANUFACTURING


     3.1. Manufacturing procedures

The manufacturer must ensure the competent execution of the provisions set out at the design stage by applying the appropriate techniques and relevant procedures, especially with a view to the aspects set out below.

    3.1.1 Preparation of the component parts

Preparation of the component parts (e.g. forming and chamfering) must not give rise to defects or cracks or changes in the mechanical characteristics likely to be detrimental to the safety of the pressure equipment.

    3.1.2 Permanent joining

Permanent joints and adjacent zones must be free of any surface or internal defects detrimental to the safety of the equipment.

The properties of permanent joints must meet the minimum properties specified for the materials to be joined unless other relevant property values are specifically taken into account in the design calculations.

For pressure equipment, permanent joining of components which contribute to the pressure resistance of equipment and components which are directly attached to them must be carried out by suitably qualified personnel according to suitable operating procedures.

For pressure equipment in categories II, III and IV, operating procedures and personnel must be approved by a competent third party which, at the manufacturer's discretion, may be:

    
 -  a notified body,    
 -  a third-party organisation recognised by a Member State as provided for in Article 13.

To carry out these approvals the third party must perform examinations and tests as set out in the appropriate harmonised standards or equivalent examinations and tests or must have them performed.

    3.1.3 Non-destructive tests

For pressure equipment, non-destructive tests of permanent joints must be carried out by suitable qualified personnel. For pressure equipment of categories III and IV, the personnel must be approved by a third-party organisation recognised by a Member State pursuant to Article 13.

    3.1.4 Heat treatment

Where there is a risk that the manufacturing process will change the material properties to an extent which would impair the safety of the pressure equipment, suitable heat treatment must be applied at the appropriate stage of manufacture.

    3.1.5 Traceability

Suitable procedures must be established and maintained for identifying the material making up the components of the equipment which contribute to pressure resistance by suitable means from receipt, through production, up to the final test of the manufactured pressure equipment.

     3.2. Final assessment

Pressure equipment must be subjected to final assessment as described below.

    3.2.1 Final inspection

Pressure equipment must undergo a final inspection to assess visually and by examination of the accompanying documents compliance with the requirements of the Directive. Test carried out during manufacture may be taken into account. As far as is necessary on safety grounds, the final inspection must be carried out internally and externally on every part of the equipment, where appropriate in the course of manufacture (e.g. where examination during the final inspection is no longer possible).

    3.2.2 Proof test

Final assessment of pressure equipment must include a test for the pressure containment aspect, which will normally take the form of a hydrostatic pressure test at a pressure at least equal, where appropriate, to the value laid down in 7.4.

For category 1 series-produced pressure equipment, this test may be performed on a statistical basis.

Where the hydrostatic pressure test is harmful or impractical, other tests of a recognised value may be carried out. For tests other than the hydrostatic pressure test, additional measures, such as non-destructive tests or other methods of equivalent validity, must be applied before those tests are carried out.

    3.2.3 Inspection of safety devices

For assemblies, the final assessment must also include a check of the safety devices intended to check full compliance with the requirements referred to in 2.10.

     3.3. Marking and labelling

In addition to the CE marking referred to in Article 15, the following information must be provided:

(a) for all pressure equipment:


    
 -  the name and address or other means of identification of the manufacturer and, where appropriate, of his authorised representative established within the Community,    
 -  the year of manufacture,    
 -  identification of the pressure equipment according to its nature, such as type, series or batch identification and serial number,    
 -  essential maximum/minimum allowable limits;

(b) depending on the type of pressure equipment, further information necessary for safe installation, operation or use and, where applicable, maintenance and periodic inspection such as:



    
 -  the volume V of the pressure equipment in L,    
 -  the nominal size for piping DN,    
 -  the test pressure PT applied in bar and date,    
 -  safety device set pressure in bar,    
 -  output of the pressure equipment in kW,    
 -  supply voltage in V (volts),    
 -  intended use,    
 -  filling ratio kg/L,    
 -  maximum filling mass in kg,    
 -  tare mass in kg,    
 -  the product group;

(c) where necessary, warnings fixed to the pressure equipment drawing attention to misuse which experience has shown might occur.

The CE marking and the required information must be given on the pressure equipment or on a dataplate firmly attached to it, with the following exceptions:

    
 -  where applicable, appropriate documentation may be used to avoid repetitive marking of individual parts such as piping components, intended for the same assembly. This applies to CE marking and other marking and labelling referred to in this Annex;    
 -  where the pressure equipment is too small, e.g. accessories, the information referred to in (b) may be given on a label attached to that pressure equipment;    
 -  labelling or other adequate means may be used for the mass to be filled and the warnings referred to in (c), provided it remains legible for the appropriate period of time.

     3.4. Operating instructions

(a) When pressure equipment is placed on the market, it must be accompanied, as far as relevant, with instructions for the user, containing all the necessary safety information relating to:


    
 -  mounting including assembling of different pieces of pressure equipment,    
 -  putting into service,    
 -  use,    
 -  maintenance including checks by the user;

(b) Instructions must cover information affixed to the pressure equipment in accordance with 3.3, with the exception of serial identification, and must be accompanied, where appropriate, by the technical documents, drawings and diagrams necessary for a full understanding of these instructions;

(c) If appropriate, these instructions must also refer to hazards arising from misuse in accordance with 1.3 and particular features of the design in accordance with 2.2.3.

     4. MATERIALS
Materials used for the manufacture of pressure equipment must be suitable for such application during the scheduled lifetime unless replacement is foreseen.

Welding consumables and other joining materials need fulfil only the relevant requirements of 4.1, 4.2(a) and the first paragraph of 4.3, in an appropriate way, both individually and in a joined structure.

     4.1 Materials for pressurised parts must:

(a) have appropriate properties for all operating conditions which are reasonably foreseeable and for all test conditions, and in particular they should be sufficiently ductile and tough. Where appropriate, the characteristics of the materials must comply with the requirements of 7.5. Moreover, due care should be exercised in particular in selecting materials in order to prevent brittle-type fracture where necessary; where for specific reasons brittle material has to be used appropriate measures must be taken;

(b) be sufficiently chemically resistant to the fluid contained in the pressure equipment; the chemical and physical properties necessary for operational safety must not be significantly affected within the scheduled lifetime of the equipment;

(c) not be significantly affected by ageing;

(d) be suitable for the intended processing procedures;

(e) be selected in order to avoid significant undesirable effects when the various materials are put together.

     4.2.

(a) The pressure equipment manufacturer must define in an appropriate manner the values necessary for the design calculations referred to in 2.2.3 and the essential characteristics of the materials and their treatment referred to in 4.1;

(b) the manufacturer must provide in his technical documentation elements relating to compliance with the materials specification of the Directive in one of the following forms:


    
 -  by using materials which comply with harmonised standards,    
 -  by using materials covered by a European approval of pressure equipment materials in accordance with Article 11,    
 -  by a particular material appraisal;

(c) for pressure equipment in categories III and IV, particular appraisal as referred to in the third indent of (b) must be performed by the notified body in charge of conformity assessment procedures for the pressure equipment.

     4.3. The equipment manufacturer must take appropriate measures to ensure that the material used conforms with the required specification. In particular, documentation prepared by the material manufacturer affirming compliance with a specification must be obtained for all materials.

For the main pressure-bearing parts of equipment in categories II, III and IV, this must take the form of a certificate of specific product control.

Where a material manufacturer has an appropriate quality-assurance system, certified by a competent body established within the Community and having undergone a specific assessment for materials, certificates issued by the manufacturer are presumed to certify conformity with the relevant requirements of this section.

    
 -  steam and hot-water generators as referred to in Article 3, section 1.2, such as fired steam and hot-water boilers, superheaters and reheaters, waste-heat boilers, waste incineration boilers, electrode or immersion-type electrically heated boilers, pressure cookers, together with their accessories and where applicable their systems for treatment of feedwater and for fuel supply, and    
 -  process-heating equipment for other than steam and hot water generation falling under Article 3, section 1.1, such as heaters for chemical and other similar processes and pressurised food-processing equipment.

This pressure equipment must be calculated, designed and constructed so as to avoid to minimise risks of a significant loss of containment from overheating. In particular it must be ensured, where applicable, that:

(a) appropriate means of protection are provided to restrict operating parameters such as heat input, heat take-off and, where applicable, fluid level so as to avoid any risk of local and general overheating,

(b) sampling points are provided where required to allow evaluation of the properties of the fluid so as to avoid risks related to deposits and/or corrosion,

(c) adequate provisions are made to eliminate risks of damage from deposits,

(d) means of safe removal of residual heat after shutdown are provided,

(e) steps are taken to avoid a dangerous accumulation of ignitable mixtures of combustible substances and air, or flame blowback.

     6. PIPING AS REFERRED TO IN ARTICLE 3, SECTION 1.3
Design and construction must ensure:

(a) that the risk of overstressing from inadmissible free movement or excessive forces being produced, e.g. on flanges, connections, bellows or hoses, is adequately controlled by means such as support, constraint, anchoring, alignment and pre-tension;

(b) that where there is a possibility of condensation occurring inside pipes for gaseous fluids, means are provided for drainage and removal of deposits from low areas to avoid damage from water hammer or corrosion;

(c) that due consideration is given to the potential damage from turbulence and formation of vortices; the relevant parts of 2.7 are applicable;

(d) that due consideration is given to the risk of fatigue due to vibrations in pipes;

(e) that, where fluids of Group 1 are contained in the piping, appropriate means are provided to isolate `take-off' pipes the size of which represents a significant risk;

(f) that the risk of inadvertent discharge is minimised; the take-off points must be clearly marked on the permanent side, indicating the fluid contained;

(g) that the position and route of underground piping is at least recorded in the technical documentation to facilitate safe maintenance, inspection or repair.

     7. SPECIFIC QUANTITATIVE REQUIREMENTS FOR CERTAIN PRESSURE EQUIPMENT
The following provisions apply as a general rule. However, where they are not applied, including in cases where materials are not specifically referred to and no harmonised standards are applied, the manufacturer must demonstrate that appropriate measures have been taken to achieve an equivalent overall level of safety.

This section is an integral part of Annex 1. The provisions laid down in this section supplement the essential requirements of sections 1 to 6 for the pressure equipment to which they apply.

     7.1. Allowable stresses

    7.1.1 Symbols

Re/t, yield limit, indicates the value at the calculation temperature of:

    
 -  the upper flow limit for a material presenting upper and lower flow limits,    
 -  the 1.0% proof strength of austenitic steel and non-alloyed aluminium,    
 -  the 0.2% proof strength in other cases.

Rm/20 indicates the minimum value of the ultimate strength 20°C.

Rm/t designates the ultimate strength at the calculation temperature.

    7.1.2 The permissible general membrane stress for predominantly static loads and for temperatures outside the range in which creep is significant must not exceed the smaller of the following values, according to the material used:

    
 -  in the case of ferric steel including normalised (normalised rolled) steel and excluding fine-grained steel and specially heat-treated steel, 2/3 of Re/t and 5/12 of Rm/20    
 -  in the case of austenitic steel:
    
 -  if its elongation after rupture exceeds 30%, 2/3 of Re/t    
 -  or, alternatively, and if its elongation after rupture exceeds 35%, 5/6 of Re/t and 1/3 of Rm/t;

    
 -  in the case of non-alloy or low-alloy cast steel, 10/19 Re/t and 1/3 of Rm/20;    
 -  in the case of aluminium, 2/3 of Re/t;    
 -  in the case of aluminium alloys excluding precipitation hardening alloys 2/3 of Re/t and 5/12 of Rm/20.

     7.2. Joint coefficients

For welded joints, the joint coefficient must not exceed the following values:

    
 -  for equipment subject to destructive and non-destructive tests which confirm that the whole series of joints show no significant defects: 1,    
 -  for equipment subject to random non-destructive testing: 0.85,    
 -  for equipment not subject to non-destructive testing other than visual inspection: 0.7.

If necessary, the type of stress and the mechanical and technological properties of the joint must also be taken into account.

     7.3. Pressure limiting devices, particularly for pressure vessels

The momentary pressure surge referred to in 2.11.2 must be kept to 10% of the maximum allowable pressure.

     7.4. Hydrostatic test pressure

For pressure vessels, the hydrostatic test pressure referred to in 3.2.2 must be no less than:

    
 -  that corresponding to the maximum loading to which the pressure equipment may be subject in service taking into account its maximum allowable pressure and its maximum allowable temperature, multiplied by the coefficient 1.25 or    
 -  the maximum allowable pressure multiplied by the coefficient 1.43, whichever is the greater.

     7.5. Material characteristics

Unless other values are required in accordance with other criteria that must be taken into account, a steel is considered as sufficiently ductile to satisfy 4.1(a) if, in a tensile test carried out by a standard procedure, its elongation after rupture is no less than 14% and its bending rupture energy measured on an ISO IV test-piece is no less than 27 J, at a temperature not greater than 20°C but not higher than the lowest scheduled operating temperature.

Regulation 12


(Annex II to the Pressure Equipment Directive)


CONFORMITY ASSESSMENT TABLES

     1. The references in the tables to categories of modules are the following:

I = Module A

II = Modules A1, D1, E1

III = Modules B1+D, B1+F, B+E, B+C1, H

IV = Modules B+D, B+F, G, H1

     2. The safety accessories defined in Article 1, Section 2.1.3, and referred to in Article 3, Section 1.4, are classified in category IV. However, by way of exception, safety accessories manufactured for specific equipment may be classified in the same category as the equipment they protect.

     3. The pressure accessories defined in Article 1, Section 2.1.4, and referred to in Article 3, Section 1.4, are classified on the basis of:

    
 -  their maximum allowable pressure PS, and    
 -  their volume V or their nominal size DN, as appropriate, and    
 -  the group of fluids for which they are intended,

and the appropriate table for vessels or piping is to be used to determine the conformity assessment category.

Where both the volume and the nominal size are considered appropriate in the second indent, the pressure accessory must be classified in the highest category.

     4. The demarcation lines in the following conformity assessment tables indicate the upper limit for each category.

Table 1
Vessels referred to in Article 3, Section 1.1(a), first indent
Exceptionally, vessels intended to contain an unstable gas and falling within categories I or II on the basis of Table 1 must be classified in category III.





Table 2
Vessels referred to in Article 3, Section 1.1(a), second indent
Exceptionally, portable extinguishers and bottles for breathing equipment must be classified at least in category III





Table 3
Vessels referred to in Article 3, Section 1.1(b), first indent




Table 4
Vessels referred to in Article 3, Section 1.1(b), second indent
Exceptionally, assemblies intended for generating warm water as referred to in Article 3, Section 2.3, must be subject either to an EC design examination (Module B1) with respect to their conformity with the essential requirements referred to in Sections 2.10, 2.11, 3.4, 5(a) and 5(d) of Annex I, or to full quality assurance (Module H).





Table 5
Pressure equipment referred to in Article 3, Section 1.2
Exceptionally, the design of pressure-cookers must be subject to a conformity assessment procedure equivalent to at least one of the category III modules.





Table 6
Piping referred to in Article 3, Section 1.3(a), first indent
Exceptionally, piping intended for unstable gases and falling within categories I or II on the basis of Table 6 must be classified in category III.





Table 7
Piping referred to in Article 3, Section 1.3(a), second indent
Exceptionally, all piping containing fluids at a temperature greater than 350°C and falling within category II on the basis of Table 7 must be classified in category III.





Table 8
Piping referred to in Article 3, Section 1.3(b), first indent




Table 9
Piping referred to in Article 3, Section 1.3(b), second indent