Mill Girth Gear Cast Iron Custom Large Diameter Ring Gear Rotary

Mill Girth Gear Cast Iron Custom Large Diameter Ring Gear Rotary Large Girth Gear

1. Technical requirements of large gear ring for mill girth gear

(1) The surface pretreatment before quenching is normalized, and the hardness should be HB210~250; Mechanical properties are strength limit Rb690MPa, yield limit Rs490MPa, elongation d511%, area reduction w25%, impact toughness value Ak30J. Tooth induction hardening, hardness of HRC50~55; Effective hardening depth 3~5mm.

(2) Ultrasonic inspection shall be carried out on the whole, and the internal quality shall meet the secondary requirements stipulated in GB7233-87 standard; Gear tooth and transition fillet magnetic particle inspection, quality should meet GB/T9444-88 standard requirements.

(3) Uncast rounded corners R5~R10.

(4) Chamfering of both ends and edges along the tooth width. Big gear ring by two half gear ring connected with high strength bolts into a whole gear ring, the joint surface must be in the center of the tooth bottom.

2. Product parameters of big ring for mill girth gear

3. Manufacturing process of big tooth ring for mill girth gear

(1) Blank

The steel casting blank is provided by the heavy casting and forging Plant of CITIC Heavy Industry Machinery Co., LTD. It is implemented in accordance with gb11352-89 standard. Molding, smelting, pouring, box beating, cleaning and dressing castings according to casting process requirements; During the inspection and acceptance, the cast steel blank shall be checked according to the drawings and technical requirements, and the process shall be put down after passing the acceptance according to JB/T6402-92 standard.

(2) Rough machining

Draw lines according to the requirements of the drawings and set aside processing allowance, alignment, connection, processing inner and outer circle, milling joint surface, drilling and other processes.

(3) Agent injury

Ultrasonic inspection shall be carried out on the whole, and the internal quality shall meet the secondary requirements of GB7233-87 standard.

(4) Normalizing pretreatment

The half ring is normalized and tempered in pairs to provide good microstructure for subsequent surface quenching. And according to the requirements of the drawings to check the deformation of half gear ring after heat treatment.

4. Case introduction of large ring gear

Citic Pacific's SINO iron project in Australia, the world's largest 7.9 x 13.6 m ball mill first big gear ring recently in a casting casting factory citic juki company success Sand production line. With a diameter of 12 meters and the height of a four-story building when broken, the size of the blank is the largest ever produced by Citic Heavy Machinery Company. At the same time, the casting also refreshed with the invention of the company and even heavy machinery industry records. First, 375 tons of molten steel was used, and second, 6 furnaces and 5 cladding casting were used to achieve this, breaking the company's record of 346 tons of molten steel set in 2007 by Saudi "Kiln King" wheel. Third, the quality scale requested for the company's similar products ever high. SINO Iron Mine is the world's largest mine project invested by CITIC Pacific in Australia together with steel groups such as Wuhan Iron and Steel Co., LTD. Citic heavy machinery for the development of the world's most progress, the specifications of the largest 5 group 1 (2) x 11 meters from the mill and 7.9 x 13.6 meters of ball mill, and will it as a "zero project".

Luoyang Zhongtai Industries Co., Ltd. The company was founded in 1981 and finished joint stock reform in 2005. There are eight subsidiaries and it's an independent legal entity with the qualifications of operating import & export trade.

With a garden-like industrial park and modern standard plant covering 80,000 square meters, ZTIC possesses advanced equipments, technologies and detecting methods. After more than 30 years development, the company has developed into a collectivized one with product designing, manufacture, installation and technical services as a whole. The products comprise all the equipments used in mining, cement, metallurgy, construction as well as the related accessories with high power reducer and large-sized castings & forgings, etc.

ZTIC has acquired ISO 9001:2008 Certification of conformity of Management System Certification, Mine Product Safety Authentication, Recognition for BV Mode Ⅱ Survey Scheme in France, Mining Electrical Equipment KY Certification, etc.
The company has also acquired "Fully Quality Management Achievement Award", "Top 50 Enterprises", "Henan Outstanding Innovative Enterprise” and “The Most Powerful Enterprises of Henan" in 2010.

Quality product performance and good reputation, our products have been exported to mnay countries and regions in the world, including: Russia, Serbia, Australia, Mongolia, Indonesia, Bangladesh and other countries, the products are subject to a great welcome and praise.