NATIONAL ALUMINIUM COMPANY LIMITED - Rites

3.0 CONSTRUCTION REQUIREMENTS
3.1 Water Supply Pumps for DS/SW/PW/CW
3.1.1 Casing Axial or radially split with drain & vent connection
3.1.2 Impeller One piece, keyed to shaft along with locking device
3.1.3 Shaft Critical speed atleast 20% away from operating speed
3.1.4 Shaft sleeves at bearings & stuffing boxes.
3.1.5 Bearings Antifriction type
3.1.6 Wearing rings Renewable type (preferable)
3.1.7 Pump speed Below 1500 rpm for capacity more than 10 cub. m/hr.
3.1.8 Head flow characteristics Suitable for parallel operation.
3.1.9 Materials
(a) Casing: Cast Iron to IS:210, FG 260
(b) Impeller: Bronze conforming to Gr.I of IS:318
(c) Impeller Wearing ring: Bronze conforming to Gr.I of IS:318
(d) Casing Wearing ring: Bronze conforming to Gr.I of IS:318
(e) Shaft: Medium carbon steel
(f) Shaft sleeve: Stainless steel conforming to AISI AISI-416 hardened.
(g) Gland packing: Impregnated Teflon
3.2.0 Sump Pumps
3.2.1 Type: Vertical, centrifugal, single st stage, age, semi open or open (non clogging) type impeller.
3.2.2 Duty: Intermittent. However, to be designed for contineous operation.
3.2.3 Fluid to be Pumped: Sludge/Coal slurry
3.2.4 Suction Condition: Submerged
3.2.5 Pump speed (maximum): 1000 RPM
3.2.6 Type of coupling between pump and motor: Directly driven through flexible or rigid
coupling/V-Belt
3.2.7 Location of pump thrust bearing: In motor stool
3.2.8 Materials
(a) Casing: Alloy Cast Iron (350 BHN) (min. 2.7% Ni, 1% Cr.)
(b) Impeller: Alloy Cast Iron (350 BHN) (min. 2.7% Ni, 1% Cr.)
(c) Impeller: Shaft Stainless steel
(d) Line Shaft: EN-8 8 to BS; 970
(e) Column pipe and discharge pipe: Fabricated steel to IS: 226 (min. 6mm thick).
(f) Shaft sleeve: Hardened stainless steel to 400 BHN
(g) Base Plate: Steel to IS: 226 up to 20mm thickness and IS: 2062 over 20mm thickness.
3.2.9 Accessories Provided with the Pump
i. Lubrication and sealing water system: Yes
ii. Common base plate for Pumps and Motor and Motor stool: Yes
iii. Anchor Bolts, nuts, sleeves and inserts (which will be embedded in concrete): Yes
iv. Coupling, guards lifting lug, eye bolt, positioning Dove: Yes
Technical Specification:Sec-4,System System Parameters, Operation & Control Philosophy
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