SIST EN 14876:2007
(Main)Transportable gas cylinders - Periodic inspection and testing of welded steel pressure drums
Transportable gas cylinders - Periodic inspection and testing of welded steel pressure drums
This European Standard deals with welded steel transportable pressure drums intended for compressed and liquefied gases under pressure of water capacity from 150 litres up to 1 000 litres.
This European Standard specifies the requirements for periodic inspection and testing to verify the integrity of such pressure drums to be re-introduced into service for a further period of time. It also defines a procedure to qualify existing pressure drums for free movement between member states of the European Union (see Annex A).
Ortsbewegliche Gasflaschen - Wiederkehrende Prüfung von geschweißten Fässern aus Stahl
Diese Europäische Norm behandelt geschweißte, ortsbewegliche Fässer aus Stahl für verdichtete und Flüssiggase mit einem Fassungsraum von 150 l bis zu 1 000 l.
Diese Europäische Norm legt Anforderungen an die wiederkehrende Prüfung fest, um die Unversehrtheit derartiger Fässer für die weitere Nutzung zu bestätigen. Sie legt auch ein Verfahren zur Zulassung von vorhandenen Fässern für den freien Warenverkehr zwischen den EU-Mitgliedsländern fest (siehe Anhang A).
Bouteilles a gaz transportables - Contrôles et essais périodiques des futs a pression soudés en acier
La présente norme européenne traite des futs a pression transportables soudés en acier, destinés aux gaz comprimés et liquéfiés sous pression d'une capacité équivalente en eau de 150 a 1 000 litres.
La présente norme spécifie les exigences relatives aux contrôles et essais périodiques permettant de vérifier l'intégrité de tels futs a pression devant etre remis en service pour une période de temps supplémentaire. Elle définit également un mode opératoire conçu pour la qualification de futs a pression existants pour la libre circulation entre Etats membres de l'Union européenne (voir Annexe A).
Premične plinske jeklenke - Periodični pregledi varjenih tlačnih sodov
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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Transportable gas cylinders - Periodic inspection and testing of welded steel pressure drumsBouteilles a gaz transportables - Contrôles et essais périodiques des futs a pression soudés en acierOrtsbewegliche Gasflaschen - Wiederkehrende Prüfung von geschweißten Fässern aus StahlTa slovenski standard je istoveten z:EN 14876:2007SIST EN 14876:2007en,fr,de23.020.30MHNOHQNHPressure vessels, gas cylindersICS:SLOVENSKI
STANDARDSIST EN 14876:200701-september-2007
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14876January 2007ICS 23.020.30 English VersionTransportable gas cylinders - Periodic inspection and testing ofwelded steel pressure drumsBouteilles à gaz transportables - Contrôles et essaispériodiques des fûts à pression soudés en acierOrtsbewegliche Gasflaschen - Wiederkehrende Prüfungvon geschweißten Fässern aus StahlThis European Standard was approved by CEN on 11 November 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2007 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14876:2007: E
EN 14876:2007 (E) 2 Contents Page Foreword.3 Introduction.4 1 Scope.5 2 Normative references.5 3 Intervals between periodic inspection and test.5 4 List of procedures for periodic inspection and test.6 5 Identification of pressure drum and preparation for inspection and test.6 6 Depressurization and de-valving procedures.7 7 External visual inspection.7 8 Internal visual inspection.8 9 Supplementary tests.8 10 Inspection of openings.8 11 Pressure test.9 12 Pressure drum repair.10 13 Inspection of valves.11 14 Final operations.11 15 Rejection and rendering pressure drum unserviceable.13 Annex A (informative)
Pressure drums manufactured according to National Regulations.14 Annex B (normative)
Inspection periods.16 Annex C (normative)
Description, evaluation of defects and conditions for rejection of welded steel pressure drums at the time of visual inspection.17 Annex D (normative)
Procedure to be adopted when de-valving and when a valve is suspected to be obstructed.21 Bibliography.24
EN 14876:2007 (E) 3 Foreword This document (EN 14876:2007) has been prepared by Technical Committee CEN/TC 23 “Transportable gas cylinders”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July 2007, and conflicting national standards shall be withdrawn at the latest by July 2007. This European Standard has been submitted for reference into the RID and/or the technical annexes of the ADR. Therefore in this context the standards listed in the normative references and covering basic requirements of the RID/ADR not addressed within the present standard are normative only when the standards themselves are referred to in the RID and/or the technical annexes of the ADR. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EN 14876:2007 (E) 4 Introduction The principal aim of a periodic inspection and testing procedure is that, at the completion of the test, the pressure drums may be reintroduced into service for a further period of time. Experience of the inspection and testing of pressure drums which is specified in this European Standard is an important factor when determining whether a pressure drum should be returned into service.
EN 14876:2007 (E) 5
1 Scope This European Standard deals with welded steel transportable pressure drums intended for compressed and liquefied gases under pressure of water capacity from 150 litres up to 1 000 litres. This European Standard specifies the requirements for periodic inspection and testing to verify the integrity of such pressure drums to be re-introduced into service for a further period of time. It also defines a procedure to qualify existing pressure drums for free movement between member states of the European Union (see Annex A). 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 14208, Transportable gas cylinders — Specification for welded pressure drums up to 1 000 litre capacity for the transport of gases — Design and construction EN ISO 11114-1, Transportable gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 1: Metallic materials (ISO 11114-1:1997) EN ISO 11114-2, Transportable gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 2: Non-metallic materials (ISO 11114-2:2000) EN ISO 11621, Gas cylinders — Procedures for change of gas service (ISO 11621:1997) EN ISO 13341, Transportable gas cylinders — Fitting of valves to gas cylinders (ISO 13341:1997) EN ISO 13769, Gas cylinders — Stamp marking (ISO 13769:2002) 3 Intervals between periodic inspection and test In order to ensure continued safe operation, pressure drums shall be subjected periodically to inspection and test in accordance with Annex B. A pressure drum shall fall due for periodic inspection and test on its first receipt by filler after expiry of the interval in Annex B. NOTE 1 Table B.1 gives a list of the intervals between periodic inspections for some gases which conforms to the current RID/ADR regulations and also gives recommendations which can be subsequently adopted by the RID/ADR regulations. Provided that the pressure drum has been subjected to normal conditions of use and has not been subjected to abusive and abnormal conditions making the pressure drum unsafe, there is no requirement for the user to return a pressure drum before the contents have been used even though the test interval may have been exceeded. However, it is suggested that pressure drums are re-tested at a period not exceeding twice the normative time interval specified in Table B.1. NOTE 2 Certain products such as hydrogen fluoride require an intermediate check of wall thickness as well as the contents to be checked for pressure rise due to the generation of gases such as hydrogen. Other products such as hydrogen bromide should not be allowed to exceed one and a half times the time interval for the normative test interval in Table B.1.
EN 14876:2007 (E) 6 4 List of procedures for periodic inspection and test Each pressure drum shall be submitted to a periodic inspection and test. The following procedures form the requirements for such inspection and test, and are explained more fully in later clauses: — identification of pressure drum and preparation for inspection and test; — depressurization and de-valving operation; — external visual inspection; — visual inspection of welds; — internal visual inspection; — supplementary tests; — inspection of valve connections; — repair of pressure drums; — inspection of openings; — inspection of valves; — proof pressure test; — final operations, including drying; — rejection and rendering pressure drums unserviceable. Where pressure drums are manufactured according to National Regulations and are intended to be qualified under the Transportable Pressure Equipment Directive (TPED) for free movement and use between member states of the European Union, additional requirements are specified in Annex A. It is recommended that the above listed tests are performed in the suggested sequence. For most gases, the internal visual examination (Clause 8) should be carried out before the pressure test (Clause 11). In some cases, e.g. HCl, performing the hydraulic test first can dissolve residual product thus making the internal inspection less hazardous. Pressure drums which fail the inspection or tests shall be rejected. When after the above tests, doubts still exist as to the extent of a defect or the condition of a pressure drum, additional tests may be performed in accordance with Clause 9, until such doubts are positively resolved, or the pressure drum shall be rendered unserviceable. 5 Identification of pressure drum and preparation for inspection and test Before any work is carried out, details of the design, contents and ownership shall be identified. If it is intended to change the service of the drum, procedures in EN ISO 11621 shall be followed.
EN 14876:2007 (E) 7 6 Depressurization and de-valving procedures The pressure drum shall be depressurised and emptied in a safe and controlled manner before proceeding. Particular attention shall be paid to pressure drums that have contained flammable, oxidising or toxic gases to eliminate risks at the internal visual inspection. Additionally, as some liquefied products may not be removed from the pressure drum by venting, an additional check such as check weighing or check of the atmosphere of the pressure drum may be required. It is recommended that pressure drums containing a hazardous product are purged in a safe manner. Pressure drums with incorrect markings, unknown product contents, or those which cannot be safely emptied of product shall be set aside for special handling. Before removing any pressure retaining accessory e.g. valve, flange, a positive check shall be performed to ensure that the pressure drum does not contain any gas under pressure. This can be performed as described in Annex D using the device such as shown in Figure D.1. NOTE If the above procedure is not performed, a violent reaction can occur e.g. projection of the valve, release of toxic gas, fire etc. Pressure drums with inoperative or blocked valves shall be treated as outlined in Annex D. Provided the requirements above have been complied with, and the pressure drum has been safely depressurised, the valves and/or flanges, as applicable, may be removed. 7 External visual inspection 7.1 Preparation for external visual inspection Each pressure drum shall be cleaned and have all labels, loose coatings, corrosion products, tar, oil or other foreign matter removed from its external surface, e.g. by brushing, shot-blasting, (under controlled conditions), water jet abrasive cleaning, chemical cleaning or other methods. Care shall be taken at all times to ensure that the pressure drum is not damaged or excess amounts of the wall of the pressure drum are not removed by the cleaning application. If a fused nylon, polythene or a similar coating has been applied and is seen to be damaged, or prevents a proper inspection, then the coating shall be removed. If the coating is removed by the application of heat the temperature of the pressure drum shall not exceed 300 °C. 7.2 Inspection procedure The external surface of each pressure drum shall undergo a thorough visual inspection for: — dents, cuts, gouges, bulges, cracks, laminations or excessive wear; — heat damage, torch or electric arc burns, (as identified in Table C.1); — corrosion (as defined in Table C.2). Special attention shall be given to areas where water may be trapped; — all welds and welded attachments and the areas adjacent to them shall be checked for defects; — other defects such as illegible or unauthorized stamp markings, unauthorized additions or modifications; — integrity of all permanent attachments e.g. shrouds, lifting points, lifting pockets, rolling bands; — damage to rolling bands. Occasionally, it may be necessary to use non destructive techniques (NDT) such as dye-penetrant, to investigate potential cracks.
EN 14876:2007 (E) 8 For rejection criteria see Annex C. Pressure drums no longer suitable for continued service shall be rendered unserviceable (as defined in Clause 15). 8 Internal visual inspection Once the requirements of Clause 6 have been met, each pressure drum shall be inspected internally to identify any defects such as those listed in 7.2. Precautions shall be taken to ensure that the method of illumination presents no hazard to the person carrying out the inspection. Any internal lining or coating which may prevent a thorough examination shall be removed. Any pressure drum showing presence of foreign matter or signs of more than light surface corrosion shall be cleaned under closely controlled conditions by shot blasting, water jet abrasive cleaning, flailing, steam jet, hot water jet, rumbling, chemical cleaning or other method. Care shall be taken to avoid damage to the pressure drum. If cleaning is required the pressure drum shall be re-inspected after the cleaning operation. 9 Supplementary tests Where there is doubt concerning the type/severity of a defect found on visual inspection (see Clauses 7 and 8), or when the cleaning processes might have reduced the wall thickness, additional tests or methods of examination may be applied, e.g. ultrasonic techniques, check weighing or other non-destructive tests. Only when all doubts are eliminated may the drum be further processed (see Annex C). 10 Inspection of openings 10.1 Internal neck threads The internal threaded openings shall be visually examined, and using gauges relevant to the threads in the drum, to ensure they are: — clean and of full form; — free of damage; — free of burrs; — free of cracks; — free of other imperfections. Where there is any doubt as to the thread condition, the thread shall be checked using a threaded gauge by a person trained in gauging threads. 10.2 Damaged internal neck threads Where necessary and where the manufacturer or the competent person confirms that the design of the neck thread permits, threads may be re-tapped or re-machined to provide the required number of effective threads. After re-making, the threads shall be checked by a thread gauge. Damaged retaining assemblies shall be replaced ensuring compatibility with the intended gas service (see EN ISO 11114-1 or EN ISO 11114-2 as relevant). 10.3 Flanged openings and retaining assemblies Where the pressure drum is fitted with flanged openings, these shall be inspected to ensure that they are: — clean faced; — free of damage to the mating surfaces; — free of cuts or gouges.
EN 14876:2007 (E) 9 For retaining assemblies e.g. bolts/studs etc. it shall be ensured that: — the profile conforms to the required specification; — is free from all surface defects; — the materials are compatible with the intended gas service even though they might not be in the gas stream (see EN ISO 11114-1). 10.4 Damaged flanged openings and/or retaining assemblies Where necessary, and where the manufacturer or a competent person confirms that the design permits, damaged flange faces, both on the drum and the flange, may be re-machined to enable a pressure seal to be made on re-assembly. Damaged retaining assemblies shall be replaced ensuring compatibility with the intended gas service (see EN ISO 11114-1 or EN ISO 11114-2 as relevant). 11 Pressure test 11.1 General Each pressure drum shall be subjected to a hydraulic or pneumatic pressure test (see 11.2). 11.2 Proof pressure test When carrying out a pressure test, a fluid, normally water, shall be used as the test medium. The test shall be a proof pressure test (see 11.3) as appropriate to the design of the drum. The test pressure shall be in accordance with the stamping on the pressure drum. NOTE A pneumatic pressure test may be substituted provided that a risk assessment has been carried out. Those using pneumatic testing need to ensure, that precautions are taken to contain any energy released if a pressure drum fails. The energy required to conduct a pneumatic pressure test is considerably more than required for a hydraulic pressure test and can cause extensive damage in the event of failure if adequate precautions have not been taken. 11.3 Procedure and acceptance criteria 11.3.1 Hydraulic test 11.3.1.1 General The pressure in the pressure drum shall be increased gradually until the test pressure is reached. The pressure shall be held for a minimum of 10 min with the pressure drum isolated from the pressure source. During the test period there shall be no decrease in the recorded pressure or evidence of any leakage. Safety precautions shall be taken, even for a hydraulic test in view of the considerable stored energy in a pressure drum. 11.3.1.2 Test equipment 11.3.1.2.1 All rigid pipe work, flexible tubing, valve, fittings and components forming the pressure system of the test equipment shall be designed to withstand a pressure 1,5 times the maximum test pressure of any pressure drum that may be tested. Flexible tubing shall have sufficient wall thickness to prevent kinking. 11.3.1.2.2 There shall be two pressure gauges to at least an accuracy of Class 2,5 as defined in EN 837-1 or EN 837-3, with a scale appropriate to the test pressure. They shall be checked for accuracy against a calibrated gauge at regular intervals, and in any case not less than once a month. The pressure gauges shall be chosen such that the test pressure is approximately between 1/3 and 2/3 of the value capable of being measured on the pressure gauge and the readings are clearly visible to the test personnel.
EN 14876:2007 (E) 10 11.3.1.2.3 The design and installation of the equipment, the connection of the drums and the operating procedures, shall be such as to avoid trapping air in the system when a liquid medium is used. 11.3.1.2.4 All joints within the system shall be leak tight. 11.3.1.2.5 A pressure relief device shall be fitted to the test equipment to ensure that no pressure drum is subjected to a pressure in excess of the tolerances in 11.3.1.3.3. 11.3.1.3 Test method 11.3.1.3.1 Only one pressure drum may be tested at a time. 11.3.1.3.2 Before applying pressure the external surface of the pressure drum shall be dry. 11.3.1.3.3 The pressure applied shall not be below the test pressure and shall not exceed the test pressure by 10 % or 10 bar, whichever is the lower. 11.3.1.3.4 On attaining the test pressure the pressure drum shall be isolated from the pump and pressure held for a minimum period of 10 min. 11.3.1.3.5 If there is a leakage in the pressure system it shall be corrected and the pressure drum retested. 11.3.1.3.6 During the 10 min period that the pressure is held, the pressure registered on the pressure gauge shall remain constant. 11.3.1.3.7 There shall be no visible leakage or visible permanent deformation on the entire surface of the pressure drum. This check may be made during the 10 min the pressure is held or immediately after the pressure has been released. 11.3.1.3.8 Any pressure drum failing to conform to the requirements of this test from the pressure bearing body shall be rendered unserviceable, in accordance with Clause 15. Leaks from any mechanical joints, e.g. flanges, may be repaired and the pressure drum shall be retested. 11.3.2 Pneumatic test The pressure in the pressure drum shall be increased gradually until the test pressure is reached. The rise in pressure shall be controlled to minimize the effects of a temperature rise due to the heat of compression. The pressure shall be held for a minimum of 20 min, once a settled pressure has been achieved for at least 10 min, with the pressure drum isolated from the pressure source. During the test period there shall be no decrease in the recorded pressure or any evidence of any leakage. Safety precautions shall be taken. The pressure source shall be isolated and vented. There shall be no visible leakage (in cases where leak detection fluid has been applied to the weldments) or visible permanent deformation on the entire surface of the pressure drum. This check shall be made immediately after the pressure has been released. Any pressure drum failing to conform to the requirements of this test shall be rendered unserviceable, in accordance with Clause 15. Leaks from any joints e.g. flanges may be repaired and the pressure drum shall be retested in accordance with 11.3.2. 12 Pressure drum repair 12.1 Detection of pinholes If during the pressure test or external visual inspection, pinhole leaks are detected in a weld, the pressure drum shall be made unserviceable. No repair to pressure containing welds shall be undertaken.
EN 14876:2007 (E) 11 12.2 Other repairs Any other repairs including de-denting, replacement of fittings etc. may be carried out, provided this will not impair the integrity of the drum. All corrosion products shall be removed prior to repair. After de-denting, the requirements given in 12.3 shall be followed. 12.3 Requirements for repair 12.3.1 Major repairs as defined in 12.2 shall be performed by a competent repairer following an approved procedure, and taking into account the fabrication and testing requirements of the pressure drum design standard EN 14208. After such repairs, which may involve a high temperature (i.e. greater than 300 °C), a stress relieving or normalizing heat treatment shall be performed. This shall be performed in a controlled manner under the supervision of a competent person. The drum shall finally be pressure tested in accordance with Clause 11 and inspected as necessary for the intended gas service. 12.3.2 Minor repairs (e.g. reforming damaged fittings) not involving welding or hot-work on pressure containing parts may be carried out provided the integrity of the pressure drum is not impaired. At all times, materials compatibility shall be maintained (see EN ISO 11114-1). 13 Inspection of valves If valves are to be re-used they shall be inspected/refurbished in accordance with EN 14189. 14 Final operations 14.1 Drying, cleaning and painting 14.1.1 Drying and cleaning When required, the interior of each pressure drum shall be thoroughly dried, paying particular attention to the areas of any joggle joints, at a temperature not exceeding 300 °C immediately after pressure testing, such that there is no trace of free water. The interior of the pressure drum shall be inspected to ensure that it is dry and free from other contaminants. 14.1.2 Painting Pressure drums shall be repainted as required such that markings stamped on the pressure drum are legible. Particular attention shall be paid to crevices to ensure that they are fully covered with a layer of paint. 14.2 Fitting valves Valves shall be fitted to the pressure drum in accordance with EN ISO 13341. The applied torque shall take into account the size and form of the threads, the materials of the valve and the type of sealing material used according to the manufacturer’s recommendations. Where the use of lubricants/sealing material is permitted, only those approved for the gas service shall be used, taking specific care of pressure drums in oxidising service according to EN ISO 11114-2. 14.3 Fitting of flanges Flanges shall be refitted to pressure drums using both gasket materials and bolts/studs that are compatible with the gas service according to EN ISO 11114-1 and EN ISO 11114-2.
EN 14876:2007 (E) 12 Each drum shall be subjected to a pneumatic leak test at a minimum pressure of 6 bar when fitted as for use, with studs, nuts, joints and valves. The joints shall be tested for leaks with a leak detection solution, or by a method of equal sensitivity. The leak detection solution shall be compatible with the contained gas and with the valve material, e.g. brass exhibits stress corrosion cracking in ammoniacal solutions. 14.4 Checking of tare weight This requirement shall only apply to drums for liquefied gases. The tare of the drum shall be obtained by weighing on a machine regularly checked for accuracy. The capacity of the weighing machine shall be suitable for the tare weight of the drum. The tare shall include the mass of the drum, valve(s) and all permanent fittings. If the tare of the drum differs from the stamped tare by more than ± 2 % and is not due to reasons of damage, e.g. corrosion, the original tare shall be cancelled and the correct tare shall be marked in a permanent and legible fashion in accordance with EN ISO 13769. Particular attention shall be paid to the tare weight when replacing any valves, dip tubes, rolling bands, guards/shrouds and foot rings. 14.5 Stamp marking After satisfactory completion of the periodic inspection and test, each pressure drum shall be permanently marked, normally on a nameplate, using EN ISO 13769 as a guideline, at least with the symbol of the inspection body or test station followed by the test date. 14.6 Reference to the next date The next test date shall be shown in a clearly visible manner, such as by a label, or by stencilling, or by a disc fitted between the valve and the pressure drum. 14.7 Records Details of the present test shall be recorded by the test station and the following information shall be available: — owner’s name; — manufacturer’s or owner's serial number; — pressure drum tare; — type of test (hydraulic or pneumatic); — test pressure; — result of test (pass or fail); — present test date; — date of the next test; — identification of the inspection body or the test station; — identification of inspector; — details of any major repairs. Additionally the following items of information relating to a pressure drum shall be recorded, if possible: — drum manufacturer; — manufacturing specification;
EN 14876:2007 (E) 13 — water capacity/size; — manufacturing test date. 15 Rejection and rendering pressure drum unserviceable The decision to reject a drum may be taken at any stage during the inspection and test procedure. If it is not possible to recover a rejected drum, it shall, after notifying the owner, be made unserviceable by the testing station for holding gas under pressure so that it is impossible for any part of the drum, especially the shoulder, to be re-issued into service. In case of any disagreement, ensure that the legal implication of the contemplated action is fully understood. One or a combination of the following methods may be employed to render the pressure drum unserviceable, after ensuring that the drum is empty and free of product or pressure: — crush the pressure drum, paying particular attention to crushing both ends; — burn an irregular hole at least 10 % of the area in each of the ends and in two oth
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