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GB 5959.7-2008: Safety in electro-heat installations -- Part 7: Particular requirements for installations with electron guns
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GB 5959.7: Evolution and historical versions

Standard ID	Contents [version]	USD	STEP2	[PDF] delivered in	Standard Title (Description)	Status	PDF
GB 5959.7-2008	English	214	Add to Cart	3 days [Need to translate]	Safety in electro-heat installations -- Part 7: Particular requirements for installations with electron guns	Valid	GB 5959.7-2008
GB 5959.7-1987	English	199	Add to Cart	2 days [Need to translate]	Safety in electroheat installations--Part 7: Particular requirements for installations with electron guns	Obsolete	GB 5959.7-1987

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Basic data

Standard ID	GB 5959.7-2008 (GB5959.7-2008)
Description (Translated English)	Safety in electro-heat installations -- Part 7: Particular requirements for installations with electron guns
Sector / Industry	National Standard
Classification of Chinese Standard	K60
Classification of International Standard	25.180.10
Word Count Estimation	11,117
Date of Issue	2008-09-19
Date of Implementation	2009-06-01
Older Standard (superseded by this standard)	GB 5959.7-1987
Quoted Standard	GB/T 2900.23-2008; GB 5959.1-2005; GB 18871-2002; IEC 60204-1-2005; IEC 60364-4-43
Adopted Standard	IEC 60519-7-2008, IDT
Regulation (derived from)	Announcement of Newly Approved National Standards No. 16 of 2008 (No. 129 overall)
Issuing agency(ies)	General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China
Summary	This Chinese standard relates to a device having an electron gun (hereinafter referred to as the electron gun assembly) relating to personal devices Particular requirements for safety. This standard applies to all electric devices with electron guns. This is also applicable to the electron gun assembly and the use of preformed non- heating glow discharge electron gun assembly and the electron gun high voltage power supply. GB 5959. 1-2005"electric plant safety Part 1: General requirements"all of the requirements applicable to this standard. This standard in Chapter 6 to Chapter 16 gives the electron gun device for any additional requirements.

GB 5959.7-2008: Safety in electro-heat installations -- Part 7: Particular requirements for installations with electron guns

---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Safety in electroheat installations.Part 7. Particular requirements for installations with electron guns ICS 25.180.10 K60 National Standards of People's Republic of China GB 5959.7-2008/IEC 60519-7.2008 Replacing GB 5959.7-1987 Electric safety device Part 7. with electron guns Particular requirements (IEC 60519-7.2008, IDT) Published 2008-09-19 2009-06-01 implementation Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China Standardization Administration of China issued

Preface Ⅰ 1 Scope 1 2 Normative References 1 Terms and definitions 1 3 4 electron beam apparatus structure 2 5 type electron gun 3 6 main danger 3 7 maintenance of high-voltage electron gun chamber 3 ground 7.1 Mobile grounding device 3 7.2 Mechanical grounding device 3 7.3 automatic grounding devices 3 8 high pressure feeder 4 8.1 the high-pressure feeder cable 4 8.2 4 wire loop Bare minimum distance between the high voltage part 4 8.3 9 electric shock protection 4 10 over-current protection 4 10.1 General requirements 4 High voltage power supply 5 10.2 11 5 equipotential bonding And the control circuit 12 controls the function 5 The control circuit 5 12.1 12.2 Control Function 5 Coolant 13 5 Process risk 514 or some component caused by 14.1 Fire 5 14.2 5 explosion hazard 14.3 environmental pollution 6 14.4 health hazards 6 Vacuum System 6 14.5 15 X- ray 6 16 mark, nameplate, technical specification documents and 6 16.1 mark, nameplate, technical documentation 6 16.2 detecting, delivery, and use and maintenance of the apparatus having an electron gun 6 described GB 5959.7-2008/IEC 60519-7.2008

Foreword

This part of all except art in Chapter 16 of the mandatory content. GB 5959 "electric safety devices" has the following 13 sections. --- Part 1. General requirements (GB 5959.1-2005, IEC 60519-1.2003, IDT); --- Part 2. Particular requirements for arc furnace apparatus (GB 5959.2-2008, IEC 60519-4.2006, IDT); --- Part 3. Particular requirements for induction and conduction heating apparatus and an induction melting apparatus (GB 5959.3-2008, IEC 60519-3.2005, IDT); --- Part 4. Particular requirements (GB 5959.4-2008, IEC 60519-2.2006, IDT) resistance heating means; --- Part 41. Particular requirements for resistance heating means for heating and melting glass --- means (GB 5959.41-2004, IEC 60519-21.1998, IDT); Safety regulations plasma apparatus (GB 5959.5-1991, eqv IEC 60519-5.. 1980) --- first portion 5; --- Part 6. Safety Specification Industrial microwave heating apparatus (GB 5959.6-2008, IEC 60519-6.2002, IDT); --- Part 7. Particular requirements for the apparatus having the electron gun (GB 5959.7-2008, IEC 60519-7.2008, IDT); --- Part 8. Particular requirements for electroslag remelting furnace (GB 5959.8-2007, IEC 60519-8.2005, IDT); --- Part 9. Particular requirements (GB 5959.9-2008, IEC 60519-9.2005, IDT) high-frequency dielectric heating apparatus; --- Part 10. for industrial and commercial heating systems special requirements (IEC 60519-10.2005, to be transformed) resistor profiling; --- Part 11. electromagnetic stirring of the liquid metal, the special requirements of the transport or pouring (GB 5959.11-2000, idt IEC 60519-11.1997); --- Part 13. Particular requirements for the heating apparatus having an explosive atmosphere (GB 5959.13-2008). This is Part 7 GB 5959's. This portion IEC 60519-7.2008 "Safety electrothermal Part 7. Particular requirements for the electron gun having means" (second , English) while drafting amendments. IEC 60519-7.2008 translation drafted in accordance with this section. For ease of use, for IEC 60519-7.2008, made in this section, the following editorial changes. --- "This standard" be replaced by "this section"; --- deleted international standards foreword and preface; --- account of the requirements and high-frequency dielectric heating apparatus for the personal protection of integrated mechanical and electrical equipment, which range expansion To the relevant physical and mechanical means comprising the necessary special safety requirements; --- increase "GB 18871-2002 Ionizing Radiation Protection and Safety of Radiation Sources basic standards." This partial replacement GB 5959.7-1987 "safe heating apparatus Part VII. Particular requirements for the apparatus having the electron gun", and The latter is mainly technical changes compared as follows (listed only project name). --- According to GB 5959.1-2005 text structure, the standard increased to 11 from the original Chapter 16 chapter, number, title change all over again Row; text "present standard" to "this section"; --- full article by article number and title IEC 60519-7.2008 corresponding to the modification, the preparation according to GB/T 1.1 provisions; ---range. Add "Special requirements for personal safety device" provisions; Edit "electric equipment applicable to one or more electron guns," the scope is "applicable to all electric with electron guns Heating means "; Increase "This is also applicable to preparing and using glow discharge electron gun assembly of an electron gun of the non-heating device and the electron gun GB 5959.7-2008/IEC 60519-7.2008 High voltage power supply "; Increase the safety Part 1 "GB 5959.1-2005" electric apparatus. General Requirements "all requirements apply to this section. This section presents all the additional requirements "of the electron gun assembly in Chapter 6 through 16; --- add "2 Normative References" chapter, references GB/T 2900.23-2008, IEC 60204-1.2005, GB 5959.1- 2005, IEC 60364-4-43, GB 18871-2002 standard; 3.1 ~ 3.13 --- increase of 13 terms and definitions; --- increase in Chapter 4 to Chapter 6; --- increase "7 maintenance period of the high-pressure ground electron gun room"; Increase "mechanical grounding 7.2"; Increase "7.3 automatic grounding devices"; --- increase in Chapter 9 to Chapter 11; --- increase "and the control circuit 12 controls"; --- increase "12.1 control circuit"; --- increase "12.2 Control function"; --- increase "or risk processing certain processes member 14 due to"; --- increase "14.1 Fire"; --- increase "the risk of explosion 14.2"; --- increase "14.3 environmental pollution"; --- increase "14.4 health hazard"; --- change the original standard "vacuum system 9" and "9.1", "9.2", "9.3" to "14.5 Vacuum System"; --- delete the original standards "9.4"; --- change the original standard "6 X- rays and ultraviolet" to "15 X- ray"; --- add "16 mark, nameplate, technical documents and specifications" chapter; --- increase "16.2 detection, and delivery of the device with the electron gun use and maintenance instructions." This section was proposed by China Electrical Equipment Industrial Association. This part of the jurisdiction of the National Electric Industry Standardization Technical Committee (SAC/TC121) equipment. This section was drafted. Xi'an Jiaotong University, Xi'an Electric Furnace Institute Co., Ltd. The main drafters of this section. SOCIETY OF Liu Xiping, Zhao Weiping, Zhang Yingming. This section replaces the following previously issued as follows. --- GB 5959.7-1987. GB 5959.7-2008/IEC 60519-7.2008 Electric safety device Part 7. with electron guns Particular requirements Range 1 This part of GB 5959 provides for a special about the personal safety of the device to device (hereinafter referred to as the electron gun device) with electron guns to begging. This section applies to all electric apparatus having an electron gun. This section also applies to non-heated high-voltage power source and the electron gun assembly and the electron gun preform using glow discharge electron gun assembly. GB 5959.1-2005 "Safety heating means Part 1. General Requirements" all requirements apply to this section. This part Chapter 6 through 16 are given all the additional requirements of the electron gun assembly.

2 Normative references

Terms of the following documents constitute provisions of this section by reference in this part of GB 5959. For dated references, All subsequent amendments (excluding corrections) or revisions do not apply to this section, however, encouraged to reach an agreement under this section Whether the parties to use the latest versions of these documents. For undated reference documents, the latest versions apply to this section. GB/T 2900.23-2008 Electrotechnical term industrial heating means (IEC 60050-841.2004, IDT) GB 5959.1-2005 electric safety devices - Part 1. General requirements (IEC 60519-1.2003, IDT) GB 18871-2002 Ionizing Radiation Protection and safety of radiation sources basic standards IEC 60204-1.2005 Safety of machinery Electrical Equipment Part 1. General requirements 1) Part 4 of the building electrical apparatus IEC 60364-4-43. Safety Chapter 43. Overcurrent Protection 2) 1) Description adopt standard. GB 5226.1-2002 Safety of machinery Electrical Equipment Part 1. General requirements (current valid version) (to IEC 60204-1.2000, IDT) 2) Description adopt standard. GB 16895.5-2002 Electrical installations of buildings Part 4. Safety Chapter 43. overcurrent protection (currently valid version This) (IEC 60364-4-43.2001, IDT)

3 Terms and Definitions

GB/T 2900.23-2008 and GB 5959.1-2005 established following terms and definitions apply to this standard. 3.1 Emitted from a source (cathode or plasma), moving at high speed along a determined trajectory electron flow. [GB/T 2900.23-2008 841-30-01, modified] 3.2 Generating one or more beams are formed and accelerated electron beam system. [GB/T 2900.23-2008 841-30-08, modified] 3.3 And accelerating electrons can be drawn from an electrode having a low electrical conductivity of the medium. [GB/T 2900.23-2008 841-22-31, modified] GB 5959.7-2008/IEC 60519-7.2008 3.4 An electrode capable of emitting electrons from a medium having a low conductivity rate. If necessary, accept positive charge. [GB/T 2900.23-2008 841-22-32, modified] 3.5 The potential between the cathode and anode formed difference to generate electric field for accelerating electrons. [GB/T 2900.23-2008 841-30-29] 3.6 Providing emission electron gun acceleration voltage and the supply current. 3.7 Built-in workpiece in a vacuum chamber, the electrical connection between the anode of the electron gun high voltage power supply portion is connected to the system. 3.8 To prevent any kind of harm when the device is related to the operation of the control member. 3.9 Thin indoor air container, a workpiece is processed in the chamber. 3.10 An electron gun disposed in the vacuum chamber. NOTE. The chamber may utilize different diaphragm opening diameter and spaced from the workpiece in order to establish a pressure differential between the electron gun and the workpiece. 3.11 The electron beam generating electromagnetic coil in the heating space of displacement of the mobile surface of the object or the deflection electrode system. [GB/T 2900.23-2008 841-30-25, modified] 3.12 For changing the external electron gun solenoid or a permanent magnet of the electron beam direction. 3.13 An electromagnetic coil for focusing the electron beam, a system or a plurality of electromagnetic coils on the charging capacitor plates heated surface. [GB/T 2900.23-2008 841-30-27, modified] Electron beam apparatus structure 4 The electron beam apparatus is mainly composed of the following parts. a) an electron gun; b) high-voltage power supply; c) focusing and electron beam deflection system, comprising a current source and a control system required; d) an electron beam bending system; e) chamber and tooling; GB 5959.7-2008/IEC 60519-7.2008 f) the vacuum system; g) control system; h) attachment (power, coolant, pneumatic means, hydraulic means etc.). Note. Only some structure in a specific apparatus, e.g., no bending systems in many installations.

5 type electron gun

Electron gun is mainly used for. --- optics (e.g. the CRT, imaging, image scanning, electron microscopy); Some non---- heating means (e.g., polymer modification, food processing, sterilization, disinfection); --- all kinds of electric applications. For example, a typical applied electric melting, heating, evaporation, and surface treatment. The use of the electron gun according to the following classification. --- accelerating voltage; ---rated power; --- and electron beam pattern; --- bending and deflection of the electron beam system.

6 main danger

An electron gun for electrical heating, by its very nature, generally result in the following hazards. --- high-voltage electric shock (see Chapter 8, 9 and 11); --- X-rays (see Chapter 15); --- vacuum chamber of a high energy density due to thermal deformation is formed (see Chapter 14). Further, there may be due to an electron beam apparatus such as a vacuum apparatus (see Chapter 12) due to the danger similar components and operation of an electron gun (see Chapter 14) caused dangerous. 7 maintenance of high-voltage electron gun room Ground 7.1 Mobile grounding device After the high voltage power supply cut off, or open door position close to the electron gun electron gun chamber of the charged components during normal operation, the contact It must be preceded by a mobile grounding device to remove any residual charge. Mobile review by the grounding device is designed to be used by. High deflection ground conductor mobile grounding device shall be permanently fixed to the ground location. The ground connection point should be easy to see and easy for the operator Checks, must be clear and secure tag. 7.2 Mechanical grounding Alternatively mechanical automatic grounding devices mounted, the gun chamber when it is opened automatically mechanical action grounded. Such machines provide suitable properties Mechanical automatic grounding devices in a safe distance can be easily visually checked. 7.3 automatic grounding devices Under the following conditions may be optionally mounted an automatic grounding devices. a) When the electron gun is stopped, the automatic operation means; b) from the normal performance of automatic fault detection means of the automatic inspection system; c) a clear signal to the display opens the gun chamber of the performance of the automatic grounding means is normal; d) before confirming properly grounded grounding devices, electrical and mechanical interlock mechanism after review by the design of the gun chamber can not be opened. In the next high-voltage power supply, the device should be installed in a portable ground position easy to see. GB 5959.7-2008/IEC 60519-7.2008

8 High Pressure Feeder

8.1 high-voltage feeder cables High-pressure feeder should have sufficient dielectric strength to effectively protect the mechanical damage. Armored cable used in high voltage feeder or feeder cable conduit or a flexible hose should be built. The cable shield, a flexible hose or conduit to be Fixedly connected to a potential. When the high voltage feeder cable disposed within the conduit or flexible hose, in addition to the return conductor, the other cable can not be placed within the same. Each electron gun Should have its own conduit or flexible hose. If the high voltage terminal of the high-pressure feeder cable disposed within the conduit or flexible hose, the flexible hose or conduit to be connected to the extension Box. High pressure and low pressure feeder cables may be laid in a cable with a high-voltage feeder cables protected electromechanical cable channel or cable channel, but The groove or slot can not be used as a protective. 8.2 loop wire Each electron gun should have its own circuit wires to carry high-voltage power supply in the return beam prescribed route. The cross wire loop Load current size of the area should correspond to the electron gun, but copper wire cross-sectional area not less than 6mm2. For special electronic gun, if used Copper wire cross-section is less than the return conductor of 6mm2, should pay special attention during installation added mechanical protection, and the feed line conductors and the circuit size of at least The wire cross-sectional area corresponding to equal. Application flexibility and return conductor insulation of the cable configuration. Return conductor should be connected at the end of the workpiece or the ground near the electron gun. It is able to define a return path, return conductor in high voltage power supply should be grounded, and the voltage applied between the ground terminal and reliable link limit. If the loop wire directly to ground in the high-voltage power supply, should be particularly careful attention to the ground and comply with EMC requirements. At rated current, the voltage drop across the loop wires should not exceed 1.5V. Return conductor between the electron gun high voltage power supply thereto should Feeder installed with cable. Note 1. Each device has at least two wire loop, so that even if a failure occurs, the other can still ensure safety. The number and arrangement of the return conductor It may be determined according to the number of electrical connection of the electron gun and the electron gun chamber and the vacuum chamber. Note 2. In the apparatus having the electron gun, the electron gun around the loop current flowing through the chambers and its frame means. The minimum distance between the high voltage part exposed 8.3 For the electron gun and its power supply from the high-pressure safety clearance apparatus restrictions, because they operate in a dry, clean rooms. But using Provision should be made in the apparatus conditions using the manufacturer's instructions.

9 Protection against electric shock

Electron gun power supply should be cut off safety interlock in the following cases. --- electron gun chamber open and close the charging member; --- high-voltage cable and is incorrectly connected or disconnected; --- high voltage power supply housing is opened. In the above case, the interlock system cut off the power, the release of high pressure charge of the capacitor, the use of reliable measures do not allow any action to occur. Further, frequent opening of the various components, may occur as long as the voltage, it shall be interlocked. NOTE. In the case where more than one device or more electron gun is connected to the high voltage power supply and associated cables different sets of electron guns there may be risk of electric shock. End of these cables are not connected in this way can be charged. If there is some excess cable in the device, the danger also exists. 10 over-current protection 10.1 General requirements According to the provisions of GB 5959.1-2005, over-current protection measures should comply with the relevant standards, for example, IEC 60364-4-43 and IEC 60204-1.2005. GB 5959.7-2008/IEC 60519-7.2008 10.2 high voltage power supply High voltage power supply system should be configured by adjustable setpoint overcurrent and overvoltage protection. High voltage power supply can not be influenced over the grid voltage. 11 equipotential bonding According to GB 5959.1-2005 in Chapter 11. In order to prevent the operator may touch the voltage between the metal member, should equipotential interconnection between all the conductors, the frame and the housing. A vacuum chamber, and is connected between the electron gun high voltage power supply is particularly important housing, which comprises a working platform, cooling water, hydraulic actuators and trachea Other construction and metal structure of the equipotential bonding. Thus, all of these parts is fixed to ground. These conductors cross sectional dimensions should be matched to the current of the electron gun, but the copper not less than 6mm2. Equipotential surround the electron beam should be able to carry the workpiece to be heated and flow of an electron gun end of the connector loop, but it can not exceed the voltage drop Over 1.5V. And the control circuit 12 controls the function The control circuit 12.1 The control circuit shall conform to IEC 60204-1.2005 requirements GB 5959.1-2005 Chapter 9 and Chapter 12. 12.2 Control Function To avoid damage caused by electron beams, the electron gun should satisfy the following conditions in the operation. --- reach working pressure in the vacuum chamber; --- electron beam deflection system failures; --- electron beam bending system operation (time if necessary); --- predetermined flow rate of cooling water flow; --- electron gun valve is opened (if any). Coolant 13 The liquid cooling (e.g., the crucible inner), 6.6 GB 5959.1-2005 shall provide appropriate monitoring device. Cleanliness required coolant within the electron gun and a deflection system for cooling water to avoid agglomeration blocking. The manufacturer should be given quality coolant. It should show the direction of flow of the cooling liquid. Coolant should alarm and monitoring apparatus. Process or some dangerous member 14 due 14.1 Fire Certain treatment materials capable of forming a porous structure on a wall or curtain level, high-temperature treatment may cause burning of these porous material level Burn, then the processing furnace room should be ventilated. Such material handling equipment, such as titanium, the operator should evacuate quickly as possible, and the furnace chamber along a Length exhaust. It means having a high power electron gun often used processing furnace chamber region near the insulating oil in the transformer. The transformer should meet the safety device Equipment specification. Electron gun manufacturers should inform users about the performance and the number of transformer oil. Shop floor should be considered an oil fire and load Fire. 14.2 explosion hazard Furnace chamber when processing a different material, may cause an explosion, especially in the case where the cooling water leakage. We can not ignore any explosion Fried possibility, should the furnace chamber door locking mechanism or better measures to avoid the furnace chamber burst. GB 5959.7-2008/IEC 60519-7.2008 14.3 environmental pollution Some material processing and high-voltage transformer oil may cause some environmental pollution. If the oil-filled high-voltage transformer, the transformer should be placed in a container or pit, once the oil leak, the pit or container may aggregate All of the oil. Considering the various treatment materials, and attention to the user to check the risk of hazardous substances, if they are leaking vacuum system and/or sink Plot in the furnace room, the user should take timely measures to deal with. 14.4 health hazards In addition to radiation outside (see Chapter 15), the treated material can also cause other hazards. In cleaning the oven chamber, inhalation should be taken protective measures to avoid harm caused by lung-related diseases. Some applications, especially in the run rarefied gas may cause the electron beam of ultraviolet radiation. States should regulate the use of protective measures. 14.5 Vacuum System Pumping system should be large enough pumping capacity, shall take all protective measures to prevent operator exposure to radiation. Vacuum pump moving parts, such as belts, pulleys, etc., should be fitted with protection settings, in order to avoid accidental contact. If the vacuum chamber is large enough to enter, it should take protective measures to avoid people evacuated in the vacuum chamber. 15 X- ray With an electron gun design and installation of equipment should be able to avoid exposure to radiation hazards to the operator caused during its operation. A large amount of radiation Small shall not exceed the value of GB 18871-2002. X- ray dose depends primarily on the high voltage electron beam and the size, design and method for detecting the shield during exposure shall be The biggest boost and fast electron beam to consider. During maintenance of various parts can be detachable and re-X- ray shielding related, should be designed not to reassembly of these parts electrically Gun can not run. Further, all parts of the shield should be related to parts of the vacuum furnace chamber. 16 mark, nameplate, technical specification documents and 16.1 mark, nameplate, technical documentation Mark, nameplate and technical documents should be consistent with the provisions of Chapter 15 GB 5959.1-2005. Electrical equipment, production and distribution of high-pressure region should be specifically labeled marker should meet local requirements. Manufacturers with the electron gun assembly in the technical documentation should be pointed out that the risk of dangerous device and set t...

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