Table of Contents
1. Purpose
The purpose of this guide is to describe how classification lists for equipment, subject to some form of authority or third party inspection, can be prepared and should be handled.
2. General
2.1 Subject Definition
This guide refers to classification lists for equipment; for classification of piping systems see ref. 6.7.
Equipment in the sense of this guide means pressure vessels and related equipment types such as heater coils, loading arms etc.; machine parts, e.g. pump and compressor houses are, in most cases, not included for classification. For the definition of the concept "pressure vessel" in various countries see ref. 6.5.
2.2 Purpose of a Classification List
The purpose of a classification list is to establish, in a systematic, way, the necessity and the nature of authority approval or third party inspection of equipment.
2.3 Classification List and Authorities
The classification list for equipment is, in the majority of the countries, not a mandatory document, requiring submittal to a Pressure Vessel Authority or another authority such as a Labor Inspection. The most important exception is the Netherlands, where the classification list has a formal status.
This exceptional position warrants a separate guide for the classification list for the Dutch Pressure Vessel Authority; see ref. 6.6. For all other countries, equipment classification lists should be prepared if they can be assumed to be practical or desirable for the purpose defined under 2.2.
3. Responsibilities
The Project Manager has the overall responsibility for the preparation, checking and issue of the classification list.
The Project Engineering Group is responsible for the preparation of the classification list, inclusive of collecting the required data and information from the various data suppliers.
The Authority Engineering Group is responsible for checking the classification list and for providing advisory services during its preparation.
Other Departments and Engineering groups act as information suppliers. Reference is made to 4.3.1.
4. Guide Lines
4.1 Requirement or Need for a Classification List
The Project Manager or his delegate should, in concert with the Authority Engineer, establish whether a classification list is required, necessary or desired for the project. He should also assign the individual engineer(s) responsible for the preparation of the classification list(s).
4.2 Form, Minimum Information, Language, Units and Document Numbering
4.2.1 Basic Form
Ref. 6.6 gives the basic form as used in the Netherlands, inclusive of the variations which have become possible by creating 'electronic' versions of this form.
For non-Dutch projects, the information to be used for equipment classification should preferably be provided in electronic form, e.g. a database file or similar; this will enable the use of engineering databases as information source for the classification list. For example, quite some information for classification can be drawn from the database, from which also equipment listings are generated.
A classification list 'form' may be defined electronically, but this is not a strict requirement.
4.2.2 Minimum and Optional Information
The minimum information for classifying equipment generally comprises the following:
- item number
- manufacturer (and country of origin)
- medium description, if applicable per space (shell, tube, ...)
- phase of the medium, if applicable per space (solid, liquid, vapor, gas - often abbreviated)
- design pressure and design temperature
- volume, where applicable per space
- reason for authority, third party or client inspection (classification, usually in abbreviated form)
- requirement for authority of third party inspection (either Yes or No).
Notes:
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media descriptions will have to be abbreviated for both complex descriptions and mixtures; the use of medium codes should be considered. A detailed listing of all components is usually not possible and also not required. Very different components (e.g., steam and liquid hydrocarbons) should be conclusively described, similar components such as in hydrocarbon mixtures can be covered by a simplified description like 'C6-hydrocarbons'.
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pressures on process related documents are sometimes given in bar absolute; this should be carefully checked before this information is used.
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pressure vessel spaces include shell and tube sides, heating/cooling jackets with a single separation from the shell, heating/cooling coils if welded to a shell, two reactor spaces with a common separation, etc.
The following information on classification lists is optional and should be given for each space as applicable:
- item name
- item location (inside/outside building)
- flow diagram reference
- purchase order reference
- physical data such as flash point, atmospheric boiling point, critical temperature, vapor pressure, density etc.
- operating pressure and operating temperature
- design code
- administrative data such as manufacturer's number, client serial number, authority serial number(s) etc.
- medium and operating circumstances related data such as a hazard category ranking or NFPA-figures (notes 1 and 2)
- extent and nature of client or authority inspection (usually the result of some kind of classification and marked by e.g. indication of an inspection group, a construction code or category or a similar system
- protective systems data (e.g., for relief valves : number, set pressure, throat diameter).
Notes:
1. NFPA - National Fire Protection Association; standard 325M provides detailed information on the most important physical and hazardous properties of a large number of substances. See ref. 6.8.
2. hazard categories can be ranked by means of figures (e.g., the Netherlands) or by abbreviated descriptions (e.g., Germany or Belgium).
3. for units to be used, see 4.2.4.
The following information is practical for control of the database operations, but does not always need printing:
- revision indication per item
- document revision indication
- notes or remarks.
The actual content of a classification list for a given project shall be established on basis of the project needs, i.e. the country in which the project should be realized and the local pressure vessel regulations and customs. A few examples are contained in Attachment 7.1.
4.2.3 Language
The language on the classification list should normally be English. If required by the project manager the use of another language is possible; this is particularly the case, if the classification list will be used for presentation or information purposes to local authorities.
4.2.4 Units
The preferred units for the classification list are SI units, however, with a few exceptions such as pressure (usually expressed in bar(g)), relief valve diameters (normally expressed in mm), volumes (preferred to be in m3, but older lists often have dm3) and densities (either kg/ m3 or kg/dm3).
4.2.5 Classification List Document Numbering
The classification list document lead number is defined in ref. 6.1 as '910' and should be used unless otherwise instructed by the Project Manager. A client document number shall be added if required by the contract.
For large projects, it is often convenient to have more than one classification list, for example one per process or utility unit.
4.3 Preparation of a Classification List
4.3.1 Supply of Data
The supply of data for the classification list is a joint effort by various groups, departments and, sometimes, third parties. The overall control shall be with the Project Engineering group of the Engineering Department. Depending on the data actually to be included (see 4.2.2 above) data may be supplied by :
- the Process Engineering Department
- the Control Systems Engineering group
- the Vessel Engineering group
- the Authority Engineering group,
together forming the internal suppliers, and
- the equipment manufacturers
- the Pressure Vessel Authority
- the client,
which form together the external suppliers.
4.3.2 Filling out the Classification List
The classification list should be filled out by the Project Engineering group in concert with the internal data suppliers (Process Engineering Department etc.). The external data can be extracted from documents and correspondence received from the external suppliers or be requested from them.
4.3.3 Checking of Data
The classification list should be checked by the Project Engineering group for consistency with equipment data sheets/specifications, engineering flow diagrams and/or pressure/temperature profiles (ref. 6.2), in particular if the classification list will be used for external presentation and/or application purposes. The Authority Engineering group should make a check for:
- completeness of the data
- the way in which the data are presented (attention to be paid to units used and, superficially, correctness); "unusual" data (e.g. liquid densities below 500 kg/m3) should be verified.
4.3.4 Approval, Issue and Distribution
The classification list should be approved and issued by the Project Manager.
The classification list should be distributed internally to:
- the Process Engineering Department
- the Vessel Engineering group
- the Piping Engineering group
- the Inspection group
- the Authority Engineering group, and in some cases
- the site office.
Other departments or groups may receive a copy on request.
The external distribution includes normally the client and the Pressure Vessel Authority or a recognized third party, charged with approval/inspection work on behalf of the Pressure Vessel Authority. The necessity of this distribution is determined by the Project Manager in concert with the Authority Engineering group. See ref. 6.4.
4.3.5 Updating the Classification List
The list should be regularly updated and reissued/redistributed during the project, incorporating revisions of the initial data, adding further data as they become available from internal and external suppliers and comments from the users.
4.3.6 Software Application
The majority of classification list will be prepared by using software such as the dBase-III program; complicated software is not necessary as virtually no calculation is required to establish the classification. The limitations are usually by the format of the classification list : too many columns (printing problem) or too many records (software slowdown or memory problems).
Because the classification system is different for each country, the use of an algorithm to classify 'quickly' is not recommended; if still an algorithm will be used to classify, a careful check of the results will be required.
4.4. Conservation of Classification List
The final classification list should be conserved either in the form of a hard copy for archiving or as a software file. It is recommended to keep one hard copy of the last issue available for the case of questions from client or Pressure Vessel Authority during the administrative finalization of the project. This finalization period may well extend after Company's actual involvement with engineering and/or construction of the project.
The client should be provided with:
- the original if the classification list was prepared manually or
- a software file if agreed contractually or mutually, or
- hard copies as per contractual requirements.
The first two choices give the client the possibility to incorporate the classification list as a permanent document in his administration.
Note:
For the Dutch situation, a permanent classification list is a mandatory document for the client.
5. Flowchart
6. References
Document
Document Number |
Title | Level | |
6.1 | BN-W-UE301 | Numbering of Project Documents | 4 |
6.2 | BN-EG-UE1 | Pressure Temperature Profile | 5 |
6.3 | BN-EG-UE2 | General Rules to Establish Mechanical Design Pressures and Temperatures | 5 |
6.4 | BN-EG-UE203 |
Defining Information to be Submitted to Pressure Vessel Authorities |
5 |
6.5 | BN-EG-UE214 | Guide for the Preparation of Equipment Classification Lists for the Dutch Pressure Vessel Authority |
5 |
6.6 | BN-EG-UE215 | Definitions of Pressure Vessels and Related Authority Requirements | 5 |
6.7 | BN-EG-later | Guide for the Classification of Piping Systems for Authority Approval Purposes | 5 |
6.8 | NFPA 325M | Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids | - |
7. Attachments
7.1 Examples of Classification List Contents
Examples of Classification List Contents
A. The Netherlands
See ref. 6.6 for an extended description of the classification list for the Dutch Pressure Vessel Authority.
B. Belgium
For Belgium no classification system is prescribed by law or by regulations; an exception must be made for steam boilers/steam vessels and LPG-containing vessels, for which some regulations are contained in the "Algemeen Reglement voor de Arbeidsbescherming".
If no requirements have been formulated on basis of e.g. an operating permit grant, the system proposed by the non-official document "Bijzondere Veiligheidsvoorschriften voor Bedrijven met Belangrijke Risico's" can be used. See ref. 6.5. Otherwise, the purchaser should determine his own requirements.
A classification list is not a mandatory document and does not require presentation to authorities or a third party, but can be made for internal purposes and for discussion purposes with any third party.
It would contain the following information:
- revision indication per item
- item number
- item location
- manufacturer/country of origin
- purchase order reference
- flow diagram reference
- medium description per space
- phase of the medium per space
- atmospheric boiling point
- operating pressure and operating temperature
- design pressure and design temperature
- volume per space
- indication of inspection body
- Yes or No regarding authority/third party inspection
- inspection group (see ref. 6.5)
- notes or remarks.
C. France
For France a classification system has been defined on basis of two decrees issued in 1926 and 1943. The implementation of the requirements is, in principle, a responsibility of the French or the foreign manufacturer. Consequently, the purchaser should be aware of the French requirements.
A classification list is not a mandatory document and does not require presentation to authorities or a third party, but can be made for internal purposes and for discussion purposes with any third party.
It would contain the following information:
- revision indication per item
- item number
- item location
- manufacturer/country of origin
- purchase order reference
- flow diagram reference
- medium description per space
- phase of the medium per space
- atmospheric boiling point
- flash point
- vapor pressure
- operating pressure and operating temperature
- design pressure and design temperature
- volume per space
- indication of inspection body
- Yes or No regarding authority/third party inspection
- inspection group (e.g., CODAP construction category; see ref. 6.5)
- design code (often CODAP) o
- relief valve data (number, throat diameter, set pressure)
- notes or remarks.
D. Germany
For Germany a classification system has been defined on basis of the 'Druckbehälterverordnung' (Decree on Pressure Vessels), which itself rests on the Act on Machinery Safety. The contents of the decree are worked out in an extensive system of regulations (TRB's, Technische Regeln für Druckbehälter) and in references to other German regulations and norms.
The implementation of the requirements of the decree is, in principle, a responsibility of the German or foreign manufacturer after he has been informed so by the purchaser. Consequently, the purchaser should be aware of the German requirements.
A classification list is not a mandatory document and does not require presentation to the relevant authorities or to a third party, but can be made for internal purposes and for discussion purposes with any third party.
It would contain the following information:
- revision indication per item
- item number
- item name
- manufacturer/country of origin
- purchase order reference
- flow diagram reference
- medium description per space (specific indication of some components such as benzene of hydrogen sulfide may be necessary)
- phase of the medium per space.
- atmospheric boiling point
- flash point
- critical temperature per space
- vapor pressure
- design pressure and design temperature
- volume per space
- indication of inspection body
- Yes or No regarding authority/third party inspection
- inspection group (see ref. 6.5)
- type of inspection (first or regular)
- notes or remarks.
E. Switzerland
For Switzerland a classification system has been defined on basis of two decrees issued in 1925 and 1938 respectively. The implementation of the requirements is, in principle, a responsibility of the Swiss or foreign manufacturer after he has been informed so by the purchaser. Consequently, the purchaser should be aware of the Swiss requirements.
A classification list is not a mandatory document and does not require presentation to the Swiss Pressure Vessel Authority, but can be made for internal purposes and as information document to the Authority.
It would contain the following information:
- item number
- manufacturer/country of origin
- medium description per space
- design pressure and design temperature
- volume per space
- Yes or No regarding authority/third party inspection
- inspection group (see ref. 6.5)
- notes or remarks.
F. Portugal
For Portugal a classification system has been defined on basis of an act and a decree issued in 1974. The implementation of the requirements is, in principle, a responsibility of the Portuguese or the foreign manufacturer after he has been informed so by the purchaser. Consequently, the purchaser should be aware of the Portuguese requirements.
A classification list is not a mandatory document and does not require presentation to the Portuguese Pressure Vessel Authority or a third party, but can be made for internal purposes and as information document to the authority or the recognized Portuguese third party.
It would contain the following information:
- item number
- item name
- manufacturer/country of origin
- medium description per space
- characteristic sizes (diameter and/or length) per space
- design pressure and design temperature
- volume per space
- Yes or No regarding authority/third party inspection
- inspection group (see ref. 6.5)
- notes or remarks.
G. Norway
For Norway no specific classification system has been developed. Specific requirements have been laid down for steam boilers (which are under supervision of the Boiler authority) as well as for other types of pressure vessels, provided they (a) contain flammable substances and (b) operate above 0.5 barg; they are under the supervision of the National Inspectorate of Explosives and Flammables, with inspection by a third party. These requirements are, to a large extent, referring to internationally accepted design codes. The implementation of the Norwegian requirements is, in principle, a responsibility of the Norwegian or foreign manufacturer after he has been informed so by the purchaser. Consequently, the purchaser should be aware of the Norwegian requirements.
A classification list is not a mandatory document and does not require presentation to the Boiler Authority, the Inspectorate mentioned above or the third party. It is only prepared if client requires so.
H. Mexico
For Mexico no specific classification system has been developed, as all boiler and pressure vessel designs should be in line with American codes such as ASME and TEMA.
There is at present no detailed experience with authority inspection of boilers and/or pressure vessels in Mexico.
I. Thailand
In Thailand no specific classification system has been developed for pressure vessels until present. A definition of the concept 'pressure vessel' was not found in the Thai regulations, however, a differentiation is made between steam boilers (requiring a boiler operator as responsible person) and other pressure vessels.
The assessment of the design of boilers and pressure vessels (and also pumps and compressors) is done per site location or part thereof (area, unit or entity, that can be defined otherwise) by a Thai engineer. This engineer shall possess a license to do this type of assessment work, on basis of which he accepts the design responsibility. The responsibility for the installation of the pressure vessels is accepted on a similar basis by a second licensed engineer, who acts as inspector. Third party inspection does not relieve the purchaser from the involvement of Thai licensed engineers.
The paper work associated with this approach is described in ref. 6.5.