NATIONAL ALUMINIUM COMPANY LIMITED - Rites

15.4.17 On both faces of flap gate main plate, 20mm thick TISCRAL liner pla plate te or equivalent material
shall be provided.
15.5 DATA SHEET : CHUTES AND HOPPERS
1.0 GENERAL
1.1 Coal Parameters As specified elsewhere
2.0 DESIGN & CONSTRUCTION
2.1.0 Chutes & Hoppers
2.1.1 MinimumValley Angle: 60 degrees
2.1.2 Material :
(a) Chute work
Sliding zones & adjacent sides : 20 mm thk. TISCRAL / equivalent
No striking/ Non sliding zones : 10 mm thk MS
Chute with valley angle 80 degree and above : All four sides of 20 mm thk.
TISCRAL/equivalent material
In the zone of magnetic field of ILMS (chute above floor level) : SS-304 304 10 mm thk.
In the zone of flap gates
: 20 thk TISCRAL/ equivalent material
Discharge Hoods over head pulleys : 4 mm thk M.S. with rubber curtain
2.1.3 Size of Chutes
: Minimum 1200mm X 1000mm (inside both way ways)
2.1.4 Inspection Doors
2.1.5 Chute Construction
:Hinged & leak proof construction (min. size 35 x 45 cm)
(a) Corners: One face of removable bolted flange connection
(b) Joints Bolted: flange joints of dust tight construction
(c) Bolt size: Min. MM-16
(d) Bolts spacing: Not more than 125 mm C/C
(e) Fixing Arrangement: Bolts with plain spring washers
2.2.0 Skirt Boards
2.2.1 Length : Min. 3 m for each feeding point
2.2.2 Height : Not less than 750 mm
2.2.3 Width : 2/3 of belt width
Side plate : Min. 10 thk TISCRAL/equivalent
Top cover : 6 mm thk M.S.
2.3.0 Flap Gate
2.3.1 Type: Linear actuator operated, 2 position
2.3.2 Travel: 60 to 70 deg. (with limit switches on both sides).
2.3.3 Automatic operation
(i) Drive: Dust tight motor driven wit with suitable linkages
(ii) Minimum Actuator Rating: 2500 kg with 1 m lever arm
(iii) No. of Operation / Hr: 15 (with 10 consecutive switchings)
(iv) Protection: Travel and Thrust dependent limit Switches.
Technical Specification:Sec-4,System System Parameters, Operation & Control Philosophy
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