1. Seismic Activity
The latest version of seismic zoning map of India given in the earthquake resistant design code of India [IS 1893 (Part 1) 2002] assigns four levels of seismicity for India in terms of zone factors.
In other words, the earthquake zoning map of India divides India into 4 seismic zones (Zone 2, 3, 4 and 5) unlike its previous version, which consisted of five or six zones for the country.
According to the present zoning map, Zone 5 expects the highest level of seismicity whereas Zone 2 is associated with the lowest level of seismicity.
2. Enclosure Material of FLP Lights
Cast Al. LM6
LM6
LM6
ALUMINIUM CASTING ALLOY LM6
This alloy conforms to BS 1490:1988 LM6.
CHEMICAL COMPOSITION
% % %
Copper 0.1 max Magnesium 0.10 max Silicon 10.0-13.0
Iron 0.6 max Manganese 0.5 max Nickel 0.1 max
Zinc 0.1 max Lead 0.1 max Tin 0.05 max
Titanium 0.2 max Aluminium Remainder Others each 0.5 max
Others total 0.15 max
LM24 Aluminium Guide Call To Action
MECHANICAL PROPERTIES OF ALUMINIUM (SAND & DIECASTING) ALLOY LM6
SAND CASTING
PRESSURE DIE CASTING
GRAVITY DIE CASTING
0.2% Proof Stress (N/mm2)
60-70
120
70-80
Tensile Strength (N/mm2)
160-190
280
190-230
Elongation (%)
5
2-5
7
Impact resistance Izod (Nm)
6.0
-
9.0
Brinell Hardness
50-55
55-60
55-60
Modulus of Elasticity (x103 N/mm2)
71
71
71
Shear Strength (N/mm2)
120
-
-
STRENGTH AT ELEVATED TEMPERATURES
Tensile strength and hardness of this aluminium casting alloy decreases fairly regularly with increasing temperature and become relatively poor at 250°C.
PHYSICAL PROPERTIES OF ALUMINIUM (SAND & DIE CASTING) ALLOY LM6
Coefficient of Thermal Expansion (per °C @ 20-100°C)
0.000020
Thermal conductivity (cal/cm2/cm/°C @ 25°C)
0.34
Electrical conductivity (% copper standard @ 20°C)
37
Density (g/cm3)
2.65
Freezing range (°C) approx.
575-565
LM24 Aluminium Guide Call To Action
MACHINABILITY
Aluminium alloys of this and similar compositions are rather difficult to machine, due to their tendency to drag and to the rapid tool wear caused by their high Silicon content. Carbide-tipped tools with large rake angles and low cutting speeds give comparatively good results when cutting lubricant and coolant are employed.
CORROSION RESISTANCE
Aluminium LM6 exhibits excellent resistance to corrosion under both ordinary atmospheric and marine conditions. For the severest conditions, this property can be further enhanced by anodic treatment.
ANODISING
LM6 can be anodised by any of the common processes, the resulting film ranging in colour from grey to dark brown.
APPLICATION AND GENERAL NOTES
Having high resistance to corrosion and excellent castability, aluminium LM6 is suitable for most marine 'on deck' castings, water-cooled manifolds and jackets, motor car and road transport fittings, thin section and intricate castings such as motor housings, meter cases and switch boxes, for a very large aluminium casting, e.g. cast doors and panels where ease of casting is essential, for chemical and dye industry castings, e.g. pump parts, and for paint industry and food and domestic castings. It is especially suitable for castings that are to be welded.
The ductility of LM6 enables castings to be rectified easily or even modified in shape, e.g. simple components may be cast straight and later bent to the required contour.
LM6 is equally adaptable for sand casting and aluminium die casting (gravity die casting and pressure die casting).
It has excellent resistance to corrosion in marine environments, possesses excellent ductility, but is of medium strength and is not heat treated. Its strength falls off rapidly at high temperatures. Its elastic limit is low and there is difficulty with machining.
Aluminium Casting Alloy LM6M has a high resistance to corrosion and excellent castability.
It finds uses in numerous places due to these properties such as marine, manifolds, motor casings, cast doors, pumping applications.
It is also especially suitable where castings need to be welded together.
3. Indian Standards
IS 6665 : Code of practice for industrial lighting
IS 5571 : Selection of equipment in hazardous area.
IS- 16101 : General lighting LEDs & LED modules terms & definition
IS-16107.1 : General Requirement Part1 (2012)
IS-16107.1 : Particular requirement section 1 LED luminaries Part2 (2012)
IS 1610: 2012 : LED modules for general lights (Part 1)
IS 1610: 2012 : LED modules for performance requirement (Part 2)
IS 8224 : Electric lighting fittings for Div. 2 areas
IS 10322 : Specification for luminaries (Part-1 to 4)
IS 1913 : General safety requirements for luminaries
IS 16102 : Self-Ballasts for LED lamps for Gen Lighting Services Part 1 : Safety Requirement Part 2 : Performance Requirement IS 8913 : Methods of measurement of lamp cap temperature rise
IS 13947 : Degree of protection provided by enclosures for Switchgear & control gear
IEC 60079 : Specification for Flameproof Enclosures of Electrical Apparatus /
IS 2148 IEC 60079 – 7 : Specifications for Increased safety enclosures of electrical Apparatus /
IS 6381 IS 62471 : Photo-biological safety of lamps and lamp systems
4. Temperature Class
