1. INTENDED USE AND SCOPE OF APPLICATION
SHORV type boxes (hereinafter – the boxes) are stationary devices which are intended for arrangement of terminal blocks, control, signaling devices and other electrotechnical components for installation in hazardous areas.1
SHORV type boxes are the fourth generation of Exd enclosures with more than 25 years service life of flameproof joints.
High resistance of SHORV aluminum alloy enclosures to hydrogen sulfide exposure is confirmed in TR CU certificates. Equipment of "ZAVOD GORELTEX" Co. Ltd. conforms to the requirements of NACE International (National Association of Corrosion Engineers), standard NACE MR0175/ISO 15156 (Petroleum and natural gas industries - Materials for use in H2S-containing environments in oil and gas production).
Scope of application – outdoor and indoor hazardous areas, as per explosion protection marking, GOST 30852.13-2002 (IEC 60079-14:1996), areas with presence of combustible dust, as per GOST IEC 61241-3-2011, dangerous production facilities of I, II, III, IV hazard class supervised by Rostechnadzor and national technical supervision bodies of the CIS countries.
SHORV boxes with a window are applied for control and measuring equipment arrangement, as well as for any equipment for visual control (including monitors).
All cable glands, as well as installed devices (terminal clamps, circuit breakers, etc.) are used as per the rules specified in the description of SHORV enclosures.
2. DESCRIPTION OF THE PRODUCT DESIGN AND MEANS OF EXPLOSION PROTECTION
Boxes consist of an enclosure and a cover manufactured from modified corrosion-resistant aluminum-silicon alloy resistant to salt spray and other chemical substances including hydrogen sulfide and hydrochloric acid vapors, salty and acidimic mine waters, frictionally intrinsically safe. Upon request, the boxes can be manufactured from stainless steel grade 03Х17Н13М2 as per GOST 5632-2014 (AISI 316L), resistant to alkali and drops of hydrochloric and sulfuric acid.
Composition: Cu 0.1% Fe 0.4% Si 12-13.5% Mg 0.1% Mn 0.4% Zn 0.1% Ti 0.15% Ni 0.1% Impurities 0.3%, others - Al, or stainless steel (monel) grade 03Х17Н13М2 as per GOST 5632-2014 (AISI 316L) composition C 0.035%, Cr 16.0-18.0%, Ni 10.0-15.0 Mo 2.0- 3.0% P 0.04% S 0.03% Mn 2% Si 0.75% (often used at chemical plants and in marine equipment as it is highly strong, resistant to high temperatures and corrosion).
Cable glands are arranged on the side surfaces of the enclosure. Control boxes have inner and outer ground clamps.2
The type of explosion protection “flameproof enclosure” is reached by design features of the enclosures with parameters of flameproof joints conforming to the requirements of GOST 30852.1-2002 (IEC 60079-1-1998). Flameproof enclosures withstand explosion pressure and make its distribution to hazardous atmosphere impossible, which is confirmed by test results.
Marking applied to terminal boxes shall contain the following information:
– trademark of the manufacturing plant;
– type of the product;
– serial number and the year of production;
– explosion protection marking;
– warning sign “De-energize before opening”;
– ambient temperature range;
and other information which shall be indicated in the marking if this is required by technical documentation.
4. LIST OF REGULATORY DOCUMENTS THE PRODUCTS COMPLY WITH
GOST 12.2.007.0-75. Occupation safety standards system. Electrical equipment. General safety requirements.
GOST R IEC 60079-0-2011. Explosive atmospheres. Part 0. Equipment. General requirements
GOST IEC 60079-1-2011. Explosive atmospheres. Part 1. Equipment protection by flameproof enclosures "d"
GOST 30852.13-2002. Explosion-proof electrical apparatus. Part 14. Electrical installations in explosive gas atmospheres (other than mines).
Ch. 7.3 Electrical Installations Code, Ch. 7.4 Electrical Installations Code,
TU 3400-005-72453807-07 (original enactment) for boxes SHORV, TU 3434-003-72453807-06 for SHORV boards
1SHORV series boxes are multifunctional and can be used for solving a wide range of tasks, including their application as terminal boxes in general industrial version or for installation in a hazardous area. Peculiarities of the design of these boxes allow using them for various purposes: as terminal boxes, boxes for power clamps, boxes for arrangement of various equipment inside, as enclosures and control cabinets for potentially hazardous areas and conditions with aggressive atmosphere. It is necessary to point out the possibility of application of these products by integrated equipment manufacturers, where superior quality of mechanical processing of aluminum is put to the forefront.
2Outer and inner ground clamps are manufactured from stainless steel and can be connected to the mounting rail for terminals, mounting plate or a grounding bar. As aluminum is an excellent conductor, grounding for cable glands is provided by a contact with enclosure wall without necessity of taking additional measures for ensuring continuity of grounding circuit.
3 SHORV series boxes are approved for application in hazardous areas and are supplied with certificates (depending on the project): ATEX, TR CU – zone 1 and zone 2. SHORV series boxes can be supplied in different versions: with installation of terminals for various currents, with Ex-components as per customer’s specification or empty as an Ex-component required in the customer’s equipment during certification.
Application of modified corrosion-resistant aluminumsilicon alloy resistant to salt spray and other chemical substances including hydrogen sulfide and hydrochloric acid vapors, frictionally intrinsically safe, ensures relatively light weight of the enclosures which significantly simplifies installation on the site. This is especially noticeable on small or medium-sized enclosures.
Various combinations of cable glands are possible. Thickness of enclosure walls is sufficient for drilling threaded holes in enclosure walls for connection of cable glands of various types.
Exd enclosures of the majority of manufacturers are intended for temperatures not lower than -20°C/-25°C, further lowering of the temperature requires installation of internal nondisconnecting heater, which makes the design of the product more complex and increases its cost (enlargement of enclosure size for the arrangement of a heater and a thermostat, provision of uninterruptible power supply and application of external protective safety switch). SHORV enclosures manufactured by "ZAVOD GORELTEX" Co. Ltd. are designed and tested in conditions to -60 °C (special version for -75 °C). This is especially important for terminal boxes.
"ZAVOD GORELTEX" Co. Ltd. has a wide range of enclosures for arrangement of different equipment considering convenience of installation. It is possible to install modular circuit breakers, contactors as well as buttons and signal lamps on the cover of enclosures.
Additional support of the cover on the enclosure by means of hinges significantly simplifies installation.
Control elements of "ZAVOD GORELTEX" Co. Ltd. are small-sized, hence increasing of the enclosure depth is not necessary.
External flange on SHORV enclosures provides more convenient access to internal components.
Modified corrosion-resistant aluminum-silicon alloy has low copper content (less than 0,1%) and iron (less than 0,4%), which ensures its resistance to aggressive exposure to sea water and increases its anti-corrosion properties, as the alloy has a special form of material structure, which was reached in the process of enclosure manufacturing. The alloy is characterized by low contents of magnesium which improves anti-frictional properties of the enclosure. These advantages allow using enclosures of "ZAVOD GORELTEX" Co. Ltd. made from modified corrosion-resistant aluminum-silicon alloy instead of stainless steel enclosures.
Technology implemented during production of "ZAVOD GORELTEX" Co. Ltd. enclosures prevents formation of cracks in the enclosure, hence the additional processing of internal surface of the enclosure is not required. This enables to increase the value of heat dissipated power of the enclosure (painting of the internal surface significantly reduces thermal conductivity of enclosure walls which can lead to overheating and malfunction of electrotechnical components). Enclosures of "ZAVOD GORELTEX" Co. Ltd. can be operated for more than 30 years.
Nameplate with the name and a serial number is made from an aluminum plate and has a specially designated installation area, which conforms to GOST 30852.0-2002 (IEC 60079-0:1998).
Reinforced enclosures of larger volumes – more than 50 dm3. 100% testing of each enclosure during production.
Mounting screws with hexagonal socket in all types of explosion-proof enclosures do not point out from the threaded hole after screw tightening in accordance with GOST IEC 60079-1-2013.
TR CU certificate covers not only the enclosure but also entire assembly when control cabinets are ordered. Finished product is delivered to the customer. "ZAVOD GORELTEX" Co. Ltd. installs all required Ex-components according to the customer’s specification.
Engineering support. "ZAVOD GORELTEX" Co. Ltd. helps to select an enclosure in accordance with the requirements of the customer and provides AutoCad drawings.
Explosion-proof control elements (buttons, switches) of "ZAVOD GORELTEX" Co. Ltd. are made fully of partly of metal which increases their strength under extreme low temperatures (-60°С compared with -30°С offered by other manufacturers), as well as in case of negligent handling. Moreover, it is necessary to note the supplier base: Allen Bradley, Blumel, Scheider Electric, etc. This equipment has the highest technical characteristics, meantime beetween failures, it is easily replaced in case of failure.