The 4-petal Girth Gear manufactured by Hengin for a European customer was delivered to Qingdao Port on December 31, 2022. This is the first product of 3 Girth Gears of the same specification that the customer ordered from Hengin, and the remaining two Girth Gears will be delivered successively. Girth Gear is processed from casting blanks, and the heat treatment process is normalizing + tempering.
The basic parameters of the 4 petal Girth Gear are mold: Mn=20, number of teeth: Z=316, maximum outer diameter: D=Φ6354mm, tooth height: h=800mm, material: ZG35CrMo, weight: 23312Kg.
The technical indicators are hardness: HB230-270, tooth surface precision: MGMA9 level, UT standard: GB/T7233.1-2009 level Ⅱ, UT standard: ASMT A903 level Ⅲ.
The manufacturing difficulties of the Girth Gear are:
1. The chemical composition, heat treatment hardness, hardness and other mechanical properties of the 4-petal Girth Gear casting must be uniform.
2.4 The joint surface of the Girth Gear must be in the middle of the tooth root, and the distance between the joint surfaces is 3mm according to the drawings.
3. Since the tooth height is 800mm, the hobbing tool has high requirements, and the precision of the tooth surface must be guaranteed.
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| Girth Gear Casting Process Design |
Casting Rough |
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| Hobbing |
Finished Product |
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| Hardness 1 |
Hardness 2 |
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| UT 1 |
UT2 |
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| MT 1 |
MT 2 |
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| Chemical Composition Inspection 1 |
Chemical Composition Inspection 2 |
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| Package 1 |
Package 2 |
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| Qingdao Warehouse Lifting 1 |
Qingdao Warehouse Lifting 2 |
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| Containerized and Reinforced 1 |
Containerized and Reinforced 2 |
4. Since Girth Gear has a 4-petal structure, It will take two 40OTS containers to complete. We use the stacked packaging method, which requires a stable packaging design, accurately finds the center of gravity, Girth Gear 2 package Dimensions are 4700×1800×1900mm
and the lifting is very stable. It only needs 1 40OT container is enough, which reduces the transportation cost for customers. Hengin carefully designs the packaging plan, selects the packaging material reasonably, and takes every detail into consideration to ensure the safe delivery of the product to the customer site.
Through the production and delivery of Girth Gear this time, we are more confident in providing high-quality products that meet user needs to more customers in the future. 
