Clinker Grinders
Clinker grinders shall be of double roll construction suitable for continuous operation and designed to reduce lump size to a suitable dimensions in order to facilitate pumping through the proposed slurry pipe lines. The clinker grinder rolls shall be suitable for rotation in both the directions. Wear plates shall be provided on clinker grinder inlet and other wearing surfaces of the grinder chamber. The bearings of clinker grinders shall be protected from ash particles and shall be grease lubricated, heavy duty, roller bearings. Water sealing arrangement shall be provided at gland seals using clear water turbidity not exceeding 30 to 40 ppm. The clinker grinder shall take its drive from a motor through a gear drive. The drive for the clinker grinder shall be transmitted from the motor through a fluid coupling to the gear drive to protect the motor against excessive torque should the rolls stall or jam. One of the rolls of clinker grinder shall receive the drive from the prime mover while the other roll shall be idler type driven through a gear arrangement from the first roll. The clinker grinder speed shall not exceed 40 rpm and the grinder drive motor speed shall not exceed 1000 rpm. The clinker grinders shall be provided with a reversing mechanism to reverse the direction of the grinder rolls should an obstruction stall the grinder. Reversible drive motors shall be amply sized for frequent start-stop-reverse-stop and start duty which may occur several times the quick succession during grinder operation. Common steel fabricated based frame for grinder motor and drive shall be furnished. Grinder drive shall be so interlocked that the motor does not start till sufficient pressure is obtained in its seal water connections. Other interlocks as required for safe and reliable operations shall also be provided.
Material of construction shall be
(a) Grinder Chamber Carbon Steel (IS:226) 10 mm thick.
(b) Wear Plates 12-14% Mn. Austenitic steel plates to IS:276, 10 mm thick
(c) Grinder Rolls & teeth Hadfield’s Manganese steel (ASTM A128, 12-14% Mn) casting shop hardened to 300-BHN at all working surfaces and work hardened to 400 BHN at site.
(d) Grinder shaft Stainless Steel 304/EN-8. (e) Shaft sleeve Hardened stainless steel 410/416 (f) Clinker outlet chute 10mm thk mild steel (IS:226) lined with wear resistant liners as above.
shivajichoudhury
