GB/T 3836.1-2021 Explosive atmospheres—Part 1：Equipment—General requirements English
1 Scope
This part specifies general requirements for construction, testing and marking of Ex Equipment and Ex Components intended for use in explosive atmospheres.
This document is applicable to equipment intended to be used in explosive gas atmosphere or explosive dust atmosphere, including the equipment specified in the supplementary documents listed in this document, as general requirements for this equipment for use in explosive atmospheres.
The standard atmospheric conditions (relating to the explosion characteristics of the atmosphere) under which it may be assumed that Ex Equipment can be operated are:
——temperature -20℃ to +60℃;
——pressure 80 kPa to 110 kPa; and
——air with normal oxygen content, typically 21% v/v.
This part and the other standards supplementing this standard specify additional test requirements for Ex Equipment operating outside the standard temperature range, but further additional consideration and additional testing may be required for Ex Equipment operating outside the standard atmospheric pressure range and standard oxygen content. Such additional testing may be particularly relevant with respect to Types of Protection that depend on quenching of a flame such as ‘flameproof enclosures “d”’ (GB/T 3836.2) or limitation of energy, ‘intrinsic safety “i”’ (GB/T 3836.4).
Note 1: Although the standard atmospheric conditions above give a temperature range for the atmosphere of -20 °C to +60 °C, the normal ambient temperature range for the Ex Equipment is -20 °C to +40 °C, unless otherwise specified and marked. See 5.1.1. It is considered that -20 °C to +40 °C is appropriate for many items of Ex Equipment and that to manufacture all Ex Equipment to be suitable for a standard atmosphere upper ambient temperature of 60 °C would place unnecessary design constraints.
Note 2: Requirements given in this standard result from an ignition hazard assessment made on equipment. The ignition sources taken into account are those found associated with this type of equipment, such as hot surfaces, electromagnetic radiation, mechanically generated sparks, mechanical impacts resulting in thermite reactions, electrical arcing and static electric discharge in normal industrial environments.
Note 3: Where an explosive gas atmosphere and a combustible dust atmosphere are, or can be, present at the same time, the simultaneous presence of both often warrants additional protective measures. Additional guidance on the use of Ex Equipment in hybrid mixtures (mixture of a flammable gas or vapour with a combustible dust or combustible flyings) is given in GB/T 3836.15.
GB/T 3836 does not specify requirements for safety, other than those directly related to the explosion risk.
Ignition sources like adiabatic compression, shock waves, exothermic chemical reaction, self-ignition of dust, naked flames and hot gases/liquids, are not addressed by this standard.
Note 4: Although outside the scope of this standard, such equipment should typically be subjected to a hazard analysis that identifies and lists all of the potential sources of ignition by the equipment and the measures to be applied to prevent them becoming effective. See GB/T 3836.28.
This document is supplemented or modified by the following documents:
——GB/T 3836.2 Explosive atmospheres—Part 2: Equipment protection by flameproof enclosures “d”;
——GB/T 3836.3 Explosive atmospheres—Part 3: Equipment protection by increased safety “e”;
——GB/T 3836.4 Explosive atmospheres—Part 4: Equipment protection by intrinsic safety “i”
——GB/T 3836.5 Explosive atmospheres—Part 5: Equipment protection by pressurized enclosure "p";
——GB/T 3836.6 Explosive atmospheres—Part 6: Equipment protection by liquid immersion “o”;
——GB/T 3836.7 Explosive atmospheres—Part 7: Equipment protection by powder filling “q”;
——GB/T 3836.8 Explosive atmospheres—Part 8: Equipment protection by type of protection “n”;
——GB/T 3836.9 Explosive atmospheres—Part 9: Equipment protection by type of protection “m”;
——GB/T 3836.17 Explosive atmospheres—Part 17: Equipment protection by pressurized room “p” and artificially ventilated room “v”;
——GB/T 3836.18 Explosive atmospheres—Part 18: Intrinsically safe electrical systems;
——GB 3836.20 Explosive atmospheres—Part 20: Equipment with equipment protection level (EPL) Ga;
——GB/T 3836.22 Explosive atmospheres—Part 22: Protection of equipment and transmission system using optical radiation;
——GB/T 3836.24 Explosive atmospheres—Part 24: Equipment protection by special protection “s”;
——GB/T 3836.25 Explosive atmospheres—Part 25: Requirements for process sealing between flammable process fluids and electrical systems;
——GB/T 3836.28 Explosive atmospheres—Part 28: Non-electrical equipment for explosive atmospheres—Basic methods and requirements;
——GB/T 3836.31 Explosive atmospheres—Part 31: Equipment dust ignition protection by enclosure “t”;
——GB/T3836.32 Explosive atmospheres—Part 32: Intrinsically safe systems with electronically controlled spark duration limitation;
——GB/T 20936.1 Gas detectors for explosive atmospheres—Part 1: Performance requirements of detectors for flammable gases;
——GB/T 20936.4 Gas detectors for explosive atmospheres—Part 4: Performance requirements of open path detectors for flammable gases;
——GB/T 19518.1 Explosive atmospheres—Electrical resistance traces heating—Part 1:General and testing requirements;
——GB/T 7957 General requirements for construction, performance and explosion protected testing of caplights for use in mines susceptible to firedamp.
This document, along with the additional parts mentioned above, is not applicable to the construction of electromedical apparatus, exploders, test devices for exploders, and shot-firing circuits.
Note 5: For the purposes of this standard, "flameproof enclosure" and "flameproof type" are synonymous.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.
GB/T 70.1 Hexagon socket head cap screws (GB/T 70.1-2008, ISO 4762:2004, MOD)
GB/T 70.2 Hexagon socket button head screws (GB/T 70.2-2015, ISO 7380-1:2011, MOD)
GB/T 70.4 Hexagon socket button head screws with collar (GB/T 70.4-2015, ISO 7380-2:2011, MOD)
GB/T 77 Hexagon socket set screws with flat point (GB/T 77-2007, ISO 4026:2003, MOD)
GB/T 78 Hexagon socket set screws with cone point (GB/T 78-2007, ISO 4027:2003, MOD)
GB/T 79 Hexagon socket set screws with dog point (GB/T 79-2007, ISO 4028:2003, MOD)
GB/T 80 Hexagon socket set screws with cup point (GB/T 80-2007, ISO 4029:2003, MOD)
GB/T 197 General purpose metric screw threads—Tolerances (GB/T 197-2018, ISO 965-1:2013, MOD)
GB/T 755 Rotating electrical machines—Rating and performance (GB/T 755-2019, IEC 60034-1:2017, IDT)
GB/T 1040.2 Plastics—Determination of tensile properties—Part 2: Test conditions for moulding and extrusion plastics (GB/T 1040.2-2006, ISO 527-2:1993, IDT)
GB/T 1043
(all parts) Plastics—Determination of charpy impact properties[ISO 179 (all parts)]
GB/T 1408.1 Insulating materials—Test methods for electric strength—Part 1: Test at power frequencies (GB/T 1408.1-2016, IEC 60243-1:2013, IDT)
GB/T 1408.2 Insulating materials—Test methods for electric strength—Part 2: Additional requirements for tests using direct voltage (GB/T 1408.2-2016, 1EC 60243-2:2013, IDT)
GB/T 2423.4 Environmental testing for electric and electronic products—Part 2: Test method—Test Db: Damp heat, cyclic (12h+12h cycle) (GB/T 2423.4-2008, IEC 60068-2-30:2005, IDT)
GB/T 2516 General purpose metric screw threads—Limit deviations (GB/T 2516-2003, ISO 965-3:1998, MOD)
GB/T 2672 Hexalobular socket pan head screws (GB/T 2672-2017, ISO 14583:2011, MOD)
GB/T 3452.1 Fluid power systems—O-rings—Part 1: Inside diameters, cross-sections, tolerances and size identification code (GB/T 3452.1-2005, ISO 3601-1: 2002, MOD)
GB/T 3452.3 Housing dimensions for O-ring elastomer seals in hydraulic and pneumatic applications
GB 3836.2-2010 Explosive atmospheres—Part 2: Equipment protection by flameproof enclosures “d” (GB/T 3836.2-2021, IEC 60079-1:2014, MOD)
GB 3836.3 Explosive atmospheres—Part 3: Equipment protection by increased safety “e” (GB/T 3836. 3-2021, IEC 60079-7 :2015, MOD)
GB/T 3836.11 Explosive atmospheres—Part 11: Material characteristics for gas and vapour classification—Test methods and data (GB/T 3836.11-2017, IEC 60079-20-1:2010, IDT)
GB/T 4208 Degrees of protection provided by enclosure (IP code) (GB/T 4208-2017, IEC 60529:2013, IDT)
GB/T 4942.1 Degrees of protection provided by the integral design of rotating electrical machines (IP code)—Classification (GB/T 4942.1-2006, IEC 60034-5:2000, IDT)
GB/T 5277 Fasteners—Clearance holes for bolts and screws (GB/T 5277-1985, eqv ISO 273:1979)
GB/T 5782 Hexagon head bolts (GB/T 5782-2016, 1SO 4014:2011, MOD)
GB/T 5783 Hexagon head bolts—Full thread (GB/T 5783-2016, ISO 4017 :2014, MOD)
GB/T 6031 Rubber, vulcanized or thermoplastic—Determination of hardness(hardness between 10 IRHD and 100 IRHD) (GB/T 6031-2017, ISO 48:2010, IDT)
GB/T 6170 Hexagon nuts, style 1 (GB/T 6170-2015, ISO 4032:2012, MOD)
GB/T 7957 General requirements for construction, performance and explosion protected testing of caplights for use in mines susceptible to firedamp (GB/T 7957-2017, IEC 60079-35-1:2011 , IEC 60079-35-2:2011, NEQ)
GB/T 8897.1 Primary batteries—Part 1: General (GB/T 8897.1-2013, IEC 60086-1:2011, MOD)
GB/T 9144 General purpose metric screw threads—Preferable plan (GB/T 9144-2003, ISO 262:1998, MOD)
GB/T 9341 Plastics—Determination of flexural properties (GB/T 9341-2008, ISO 178:2001, IDT)
GB/T 11020 Flammability of solid non-metallic materials when exposed to flame sources—List of test methods (GB/T 11020-2005, IEC 60707:1999, DT)
GB/T 11026.1 Electrical insulating materials—Thermal endurance properties—Part 1: Aging procedures and evaluation of test results (GB/T 11026.1-2016, IEC 60216-1:2013, IDT)
GB/T 11026.2 Electrical insulating materials—Thermal endurance properties—Part 2: Choice of test criteria (GB/T 11026.2-2012, IEC 60216-2:2005, IDT)
GB/T 13813 Testing method and judging rule of safety to friction spark of metallic material for coal mine
GB/T 16422.2 Plastics—Methods of exposure to laboratory light sources—Part 2: Xenon-arc sources (GB/T 16422.2-2014, ISO 4892-2:2006, IDT)
GB/T 16935.1 Insulation coordination for equipment within low-voltage systems—Part 1: Principles requirements and tests (GB/T 16935.1-2008, IEC 60664-1:2007, IDT)
GB/T 17194 Conduits for electrical purposes—Outside diameters of conduits for electrical installations and threads of conduits and fittings (GB/T 17194-1997, eqv IEC 60423:1993)
GB/T 18616 Corrugated flexible metallic hose assemblies for the protection of electrical cables in explosive atmospheres (GB/T 18616-2002, eqv ISO 10807:1994)
GB/T 35685.1 Low-voltage switchgear and controlgear enclosed equipment—Part 1: Enclosed switch-disconnectors to provide isolation during repair and maintenance work (GB/T 35685.1-2017, IEC 62626-1:2014, IDT)
ANSI/UL 746C Polymeric Materials—Used in Electrical Equipment Evaluations
ASTM D5964 Standard practice for rubber IRM 901, IRM 902, and IRM 903 replacement oils for ASTM No.1, ASTM No.2, and ASTM No.3
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
——IEC: http://www.electropedia.org/
——ISO: http://www.iso.org/obp
Note: Additional definitions applicable to explosive atmospheres can be found in GB/T 2900.35.
3.1
ambient temperature
temperature of the air or other media, in the immediate vicinity of the equipment or component
Note 1: This does not refer to the temperature of any process media, unless the equipment or component is totally immersed in the process media. See 5.1.1.
Note 2: If Ex Equipment or an Ex Component is located inside or adjacent to another piece of equipment, the “ambient temperature” is the temperature of the air or other media surrounding the Ex Equipment or Ex Component and may be higher than the ambient air surrounding the complete equipment due to the additional heat dissipated within the complete equipment.
Note 3: The ambient temperature referred to in the GB/T 3836 series is only related to the explosion safety of the Ex Equipment or Ex Component.
3.2
hazardous area
area in which an explosive atmosphere is present, or may be expected to be present, in quantities such as to require special precautions for the construction, installation and use of equipment
3.3
non-hazardous area
area in which an explosive atmosphere is not expected to be present in quantities such as to require special precautions for the construction, installation and use of equipment
3.4
associated apparatus
electrical apparatus which contains both intrinsically safe and non-intrinsically safe circuits and is constructed so that the non-intrinsically safe circuits cannot adversely affect the intrinsically safe circuits
Note 1: Associated apparatus is either:
a) additionally protected by a Type of Protection suitable for use in the appropriate explosive atmosphere, or
b) not protected by a Type of Protection suitable for use in the appropriate explosive atmosphere and therefore is not to be used within an explosive atmosphere.
Note 2: In earlier editions of this standard, it was referred to as “associated equipment”.
3.5
Ex associated equipment
explosion-protected associated equipment
auxiliary equipment used in conjunction with explosion-protected equipment to maintain specific aspects of the Type of Protection of the explosion-protected equipment
Note 1: Examples include special time/current relays for increased safety motors, pressurization control systems, power limits for encapsulated Ex Equipment, and the like.
Note 2: Ex associated equipment is either:
a) additionally protected by a Type of Protection suitable for use in the appropriate explosive atmosphere, or
b) not protected by a Type of Protection suitable for use in the appropriate explosive atmosphere and therefore is not to be used within an explosive atmosphere.
Note 3: A similar concept is applied to intrinsic safety where it is referred to as “associated apparatus”. See 3.4. A single piece of equipment may include both Ex associated equipment and associated apparatus.
3.6
auto-ignition temperature, AIT
lowest temperature (of a surface) at which, under specified conditions (according to GB/T 3836.11), an ignition of a flammable gas or vapour in mixture with air or air/inert gas occurs
3.7 cells and batteries
3.7.1
battery
one or more cells fitted with devices necessary for use, for example, terminals, marking and protective devices
Note: See Figure 1 for examples of typical battery constructions.
Foreword i
Introduction xi
1 Scope
2 Normative references
3 Terms and definitions
4 Equipment grouping
5 Temperatures
6 Requirements for all electrical equipment
7 Non-metallic enclosures and non-metallic parts of enclosures
8 Metallic enclosures and metallic parts of enclosures
9 Fasteners
10 Interlocking devices
11 Bushings
12 (Reserved for future use)
13 Ex Components
14 Connection facilities
15 Connection facilities for earthing or bonding conductors
16 Entries into enclosures
17 Supplementary requirements for electrical machines
18 Supplementary requirements for switchgear
19 Supplementary requirements for fuses
20 Supplementary requirements for external plugs, socket outlets and connectors for field wiring connection
21 Supplementary requirements for luminaires
22 Supplementary requirements for caplights and handlights
23 Equipment incorporating cells and batteries
24 Documentation
25 Compliance of prototype or sample with documents
26 Type tests
27 Routine tests
28 Manufacturer's responsibility
29 Marking
30 Instructions
Annex A (Normative) Supplementary requirements for cable glands
Annex B (Normative) Requirements for Ex components
Annex C (Informative) Example of rig for resistance to impact test
Annex D (Informative) Electric machines connected to converters
Annex E (Informative) Temperature rise evaluation of electric machines
Annex F (Informative) Guidance flowchart for tests of non-metallic enclosures or non-metallic parts of enclosures (26.4)
Annex G (Informative) Guidance flowchart for tests of cable glands
Annex H (Informative) Shaft voltages resulting in electrical machine bearing or shaft brush sparking discharge energy calculation
Annex I (Nominative) Special requirements for Group I electrical apparatus
Annex J (Nominative) Inspection procedure for obtaining certificate
Bibliography
