变电站和电力网络中的保护与控制

Directional earth-fault relays

An indication of direction is obtained from the relative vectorial position of neutral current and neutral voltage. The side of the fault is identified by comparing the values measured in the network. Other methods of measurement are possible.

Frequency relays

If the frequency goes above or below set limits or fluctuates at an unacceptable rate (df/dt), this is detected, resulting in disconnection or load rejection.

Voltage relays

Voltage deviations are indicated, allowing the system load to be reduced as necessary.

Other protective devices used specifically with certain system components include interturn-fault relays, negative sequence relays, reverse-power relays for generators, Buchholz relays, temperature monitors, oil level indicators, oil and air flow indicators for transformers, and insulation monitoring for conductors.

14.2.2 Advantages of numeric relays

Static protection relays with discrete components have now been joined by digital relays equipped with microprocessors (μP). Digital devices of the same kind can perform control functions as well as protection duties. Users are coming to insist on their use.

Features of these relays include:

• Analogue variables are digitalized in the relay's input circuit and calculated in the processor.
• The entered settings act on the relay's built-in program.
• Several protective functions can be combined and executed in a single unit. All newly developed numeric protection relays are multifunction relays.
• The relays incorporate constant self-monitoring and diagnosis.
• They can be controlled from a personal computer (PC) with menu guidance in a variety of languages.
• Logic functions allow links to external signals by way of optocoupler inputs.
• Memories for recording events and disturbances enable faults to be analysed afterwards in detail from the stored data.

Serial interfaces make them easy to integrate into control and instrumentation systems.

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2 Scope

2

EUROPEAN STANDARD

NORME EUROPÉENNE

EUROPÄISCHE NORM

EN 10216-3

May 2002

ICS 23.040.10; 77.140.75

English version

Seamless steel tubes for pressure purposes –
Technical delivery conditions

Part 3: Alloy fine grain steel tubes

Tubes sans soudure en acier pour service sous pression – Conditions techniques de livraison – Partie 3: Tubes en acier allié à grain fin

Nahtlose Stahlrohre für Druckbeanspruchungen – Technische Lieferbedingungen – Teil 3: Rohre aus legierten Feinkornbaustählen

This European Standard was approved by CEN on 2002-04-25.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member.

The European Standards exist in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom.

CEN

European Committee for Standardization

Comité Européen de Normalisation

Europäisches Komitee für Normung

Management Centre: rue de Stassart 36, B-1050 Brussels

© 2002. CEN – All rights of exploitation in any form and by any means reserved worldwide for CEN national members.

Ref. No. EN 10216-3 : 2002 E

Contents

Section	Page
Foreword	3
Introduction	4
1 Scope	4
2 Normative references	5
3 Definitions	5
3.1 DN	5
3.2 PN	5
4 Designations	6
4.1 Range of PN designations	6
4.2 Range of DN (nominal sizes)	6
4.3 Gasket types	6
4.4 Information to be supplied by the purchaser	6
5 Gasket designs	6
6 Gasket types	7
7 Dimensions	7
8 Marking	10
Annex A (informative) Information to be supplied by the purchaser	10
Annex B (informative) A-deviation	11

:current

Foreword

This document (EN 10216-3:2002) has been prepared by Technical Committee EC/TC 29, "Steel tubes and fittings for steel tubes", the secretariat of which is held by UNI.

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 November 2002, and conflicting national standards shall be withdrawn at the latest by November 2002.

This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s).

For relationship with EU Directive(s), see informative annex ZA, which is an integral part of this document.

Other Parts of EN 10216 are:

Part 1:	Non-alloy steel tubes with specified room temperature properties
Part 2:	Non-alloy and alloy steel tubes with specified elevated temperature properties
Part 4:	Non-alloy and alloy steel tubes with specified low temperature properties
Part 5:	Stainless steel tubes

Another European Standard series covering tubes for pressure purposes is:

EN 10217:

Welded steel tubes for pressure purposes

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.

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1 Scope

This Part of EN 10216 specifies the technical delivery conditions in two test categories for seamless tubes of circular cross section, made of weldable alloyed fine grained steel.

2 Normative references

This European Standard incorporates by date or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For date references, subsequent amendments to or revisions of, any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments).

The requirements of this European Standard rule when they differ from those in the standards and documents referred to below:

EN 10002-1, Metallic materials - Tensile testing - Part 1: Method of test (at ambient temperature).

EN 10002-5, Metallic materials - Tensile testing - Part 5: Method of testing (at elevated temperature).

EN 10020, Definitions and classification of grades of steel.

EN 10021, General technical delivery requirements for steel and iron products.

EN 10045-1, Metallic materials - Charpy impact test - Part 1: Test method.

EN 10052, Vocabulary of heat treatment terms for ferrous products.

EN 10204, Metallic products - Types of inspection documents.

EN 10027-1, Designation systems for steels - Part 1: Steel names, principle symbols.

EN 10027-2, Designation systems for steels Part 2: Numerical systems.

ENV 10220, Seamless and welded steel tubes - Dimensions and masses per unit length

EN 10233, Metallic materials - Tubes - Flattening test.

EN 10234, Metallic materials - Tubes - Drift expanding test.

EN 10236, Metallic materials - Tubes - Ring expanding test.

EN 10237, Metallic materials - Tubes - Ring tensile test.

EN 10246-1, Non-Destructive Testing of steel tubes Part 1: Automatic electromagnetic testing of seamless and welded (except submerged arc welded) ferromagnetic steel tubes for verification of hydraulic leak-tightness.

EN 10246-5, Non-Destructive Testing of steel tubes - Part 5: Automatic full peripheral magnetic transducer/flux leakage testing of seamless and welded (except submerged arc-welded) ferromagnetic steel tubes for the detection of longitudinal imperfections.

EN 10246-6, Non-Destructive Testing of steel tubes - Part 6: Automatic full peripheral ultrasonic testing of seamless steel tubes for the detection of transverse imperfections.

EN 10246-7, Non-Destructive Testing of steel tubes - Part 7: Automatic full peripheral ultrasonic testing of seamless and welded (except submerged arc welded) steel tubes for the detection of longitudinal imperfections.

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