10.3　Furnace Cover Cradle，Furnace Cover and Furnace Cover Lifting Mechanism

10.3.1　The cradles shall be installed according to the following requirements:

1　The longitudinal and horizontal center lines shall be adjusted，and the measurement by plumb wire should be carried out，with the allowable deviation of 5.0mm.

2　The elevation shall be adjusted，and the measurement by optical instrument should be carried out，with the allowable deviation of±5.0mm.

3　The verticality of mast shall be adjusted，and the measurement by suspension wire should be carried out，with the allowable deviation of 1.0/1000.

4　The levelness of the suspension beam for furnace cover and the supporting beam for lifting mechanism shall be adjusted，and the measurement by leveler should be carried out，with the allowable deviation of 1.0/1000.

5　The quality of welds of the furnace cover cradle shall conform to the requirements of the design technical document.

10.3.2　The furnace cover and its lifting mechanism shall be installed according to the following requirements:

1　The positions of transmission device's chain wheels shall be adjusted，and the measurement by plumb wire should be carried out，with the allowable deviation of 2.0mm.

2　After the furnace cover has been suspended on the chain，the verticality of the suspended chain shall be checked with the allowable deviation of 1.0mm.

3　The drooping length of the chain shall be adjusted.The height difference of the lower edge of furnace cover shall be checked with the allowable deviation of 2D/1000（D refers to the diameter of the furnace cover）.

10.3.3　The levelness of lifting hydraulic cylinder for furnace cover shall be adjusted，and the measurement by leveler should be carried out，with the allowable deviation of 0.10/1000.The superposition of the axes of lifting hydraulic cylinder and the center of chain wheel width shall be adjusted，and the measurement by ruler should be carried out，with the allowable deviation of 1.0mm.

10.3.4　The water cooling system for the furnace cover shall be subject to a hydrostatic test and a flushing test according to the requirement of Article 9.5.5 of the code.