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Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer

China Luoyang Zhongtai Industrial Co., Ltd. certification
China Luoyang Zhongtai Industrial Co., Ltd. certification
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Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer

Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer
Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer
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Large Image :  Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer

Product Details:
Place of Origin: Henan, China
Brand Name: ZTIC
Certification: ISO/CE
Model Number: Rotary kiln Girth Gear
Payment & Shipping Terms:
Minimum Order Quantity: 1 Set/Sets
Price: negotiable / Set
Packaging Details: Simple packaging for Rotary kiln Ring Gear
Delivery Time: 1-2months
Payment Terms: D/A, D/P, L/C, Western Union, MoneyGram, T/T
Supply Ability: 2000 Set/Sets per Year
Detailed Product Description
Girth Gear: Rotary Kiln Girth Gear And Ball Mill Girth Gear Material: Alloy Steel
Diameter: Min 100 Mm To16000 Mm Girth Gear Weight: Max 120 MT Single Piece
Module Range: 10 Module To 70 Module Standards/Certificates: UNI EN ISO,AWS, ASTM,ASME,DIN
Applications: Cement And Minerals Industries Gear Cutting Machines: 16m CNC Hobbing Machine
Machining Tolerance: Max. 0.01mm Machining Roughness: Max. Ra 0.4
High Light:

40CrMo Rotating Gear Ring


Cement Plant Rotating Gear Ring


40CrMo kiln girth gear

Heavy Duty Cement Plant Dryer Rotary Kiln Gear 40CrMo Rotating Gear Ring
Product Description

We are specialized in manufacturing different type of large mechanical products according to engineer drawings.

The products include gears, pinions, sprockets, shafts, wheels, rollers, couplings, pulleys, housings ,frames, molds, nonstandard machinery parts, wear resistant parts and structural components.

Rotary kiln Girth Gear

Girth Gears offered find extensive application in different industry sectors including in sponge iron plants, steel & cement industry, mining industry, wind mills as well as in other industry sectors. These are made available in module range of 10 Module to 70 Module and in minimum diameters of 100 mm to 15000 mm. Further, these comprise maximum weight of 70 MT single pieces. Here the range of hardened & ground gear boxes/gears comprise Worm gear boxes, Helical / Double helical gears/gearboxes, Helical-Bevel gearboxes, Planetary Gearboxes and others.

Material Standard
Material Processing
Forging, Casting, Welding
Heat Treatment
Annealing, Normalizing, Q&T, Induction Hardening
Machining Tolerance
Max. 0.01mm
Machining Roughness
Max. Ra 0.4
Module of Gear
Accuracy of Teeth
Max. ISO Grade 5
100kgs - 60 000kgs
Mining, Cement, Construction, Chemical, Oil Drilling, Steel Mill, Sugar Mill and Power Plant
ISO 9001



CITIC IC Gear Cutting Machines include:

Ø16m CNC Hobbing Machine

Ø12m Gear Cutting Machine (Switzerland)

Ø10m Hobbing Machine (Germany)

Ø4m CNC High Speed Hobbing Machine (Germany)

Ø1.6m Horizontal CHC Hobbing Machine (Germany)

Ø5m CNC Profile Gear Grinding Machine (Germany)

Ø2.8m CNC Profile Gear Grinding Machine (Germany)

Ø1.25m CNC Profile Gear Grinding Machine (Germany)

Ø1m CNC Profile Gear Grinding Machine (Germany)

Ø0.8m CNC Profile Gear Grinding Machine (Germany)


Diameter : Min 100 mm to16000 mm.

Weight : Max 120 MT single piece.


Min 3 hp to  Max 1400 hp

Splash / Forced lubrication type


We provide girth gears in three different designs

1. Fabricated steel

- forged ring

- rolled plate

Cast steel 

Ductile (Nodular) cast iron  

Fabricated gears became more common in the past and are constructed with forged steel gear rim materials and electro welded body structure. The rings are manufactured from a whole block of high resistance alloy steel. After the rough machining of the ring, we carry out hardening and tempering heat treatment in order to improve the mechanical characteristic and therefore its relevant performance.  


Avantages of fabricated girth gears

1. The forged material structure excludes the risk of inclusions

2. Structure defects like gas holes, micro shrinkage, pin holes, hot tears, sand and slag inclusions are avoided

3. Hence, repair welding of the body structure and e.g. grinding of toothed areas is not required.

4. The fabricated manufacturing procedure excludes the need for patterns and risers

5. Rim material has higher hardness and higher strength than the material used for the underlying structure (i.e. web, gussets)



1. External teeth 

Maximum diameter: 16000 mm 

Toothed face width: 1700 mm 

Maximum module: 45 by hob 

Maximum module: 65 gear finishing cutter


2. Internal teeth 

Maximum Diameter: 6500 mm 

Maximum module: 25.4 

Toothed face width: 400 mm


Forging material process
Final rolling
Furnace cooling
Control on production
Water quenching
Hardness testing
Rough machining
Ultrasonic testing and dimensional inspection

Final inspection certification


Our girth gears are applied in the cement and minerals industries:
Various types of horizontal mills
Rotary dryers
Rotary kilns
Any other large gear ring application


We are leading supplier the Kiln Girth Gears for the various plants as listed below.

1. Sponge Iron Plants  50TPD 100TPD 300TPD350TPD,500TPD,1000TPD

2. Cement plants as per customer requirement

3. Gears for phosphate mines, Alumina plant, kaolin-bentonite


Gear Cutting Capacity:

1. 100mm diameter to 16000mm diameter

2. 10Module to 70Module

The Kiln girth gears are available mainly in bi-part, four parts, 8 parts or multi segments as per the requirement and suitability with the application of gear. In the field of grinding mill components, We supply mill heads,feed inlet,grinding roller,cement kiln riding ring, casting gears, shaft block .Also we supply mill shell of welding structures and fabrications.


Quality assurance documents
The following reports are to be submitted to Quality Assurance:
a. Chemistry report
b. Physical report
c. Heat treatment documents


Specification for Steel Castings for Grinding Mills
d. Ultrasonic inspection report (before and after repairs)
e. Magnetic particle inspection report (before and after repairs)
f. Dimensional report
g. Weld repair maps
h. Weld procedures and Procedure qualification record
i. Welder qualification
j. Nondestructive testing inspector qualification



Structural features

Processing measure

Test content

Girth Gear

(1)GS42CrMo4Alloy Steel (corporate proprietary standards)

HB 220~240

(2)semi-structured, Y-Spoke
(4) reasonable sealing and alignment structure of alloy steel (corporate proprietary standards)
(1) outer steel refining (R-H argon and vacuum treatment)
(2) proprietary cold mold hanging sand technology to ensure the casting, the teeth dense
(3) normalizing (proprietary technology) to ensure that the tooth surface hardness
(4)rough hobbing, release time, repair the joint surface, then fine roll
(5) proprietary homemade hob fine hobbing
(1)castings mechanical properties and chemical composition (internal standard)
(2) roughing after sonic testing
(3)semi-finishing, finishing after ultrasonic testing and magnetic particle inspection
(4) tooth surface magnetic particle inspection, hardness test
(5)tooth tolerance check
(6) the factory assembly load test to check the accuracy of the size of gear

 Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer 0

The technical requirements of a large CITICIC Gear ring:
1) is pretreated before normalizing surface hardening treatment, the hardness should HB210 ~ 250; mechanical performance are the ultimate strength Rb 690MPa, yield stress Rs 490MPa, elongation D5 11%, reduction of area W 25% , impact toughness Ak 30J; teeth induction hardened, hardness HRC50 ~ 55; effective hardened layer depth 3 ~ 5mm.
2) overall ultrasonic flaw detection, internal quality should meet two requirements GB7233-87 standard requirements; tooth and fillet magnetic particle inspection, quality should meet two requirements GB/T9444-88 standards.
3) Note the casting is not rounded R5 ~ R10.
4) Tooth chamfer at both ends and 1 45b.5) by two and a half ring gear tooth width of each ring coupling along the edge of a whole ring made with high strength bolts, combined with the tooth surface must be at the bottom center.
2 large ring gear manufacturing process
2.1 of rough
Steel casting blank is provided by CITIC Heavy Machinery Co., Ltd. Heavy Forging plant, run by GB11352-89 standard specifies requirements for modeling according to the casting process, smelting, casting, hit boxes, cleaning, dressing castings;. During inspection and acceptance by the drawings and Technical requirements for steel blank
Checks, according JB/T6402-92 standards issued after acceptance
Down procedure.
2.2 roughing
Crossed by drawing and stay out allowance, alignment, connection, processing both inside and outside the circle, combining face milling, drilling and other processes.
2.3 Exploration injury
Overall ultrasonic flaw detection, internal quality should meet the two requirements of GB7233-87 standards.
2.4 normalizing pretreatment
Semi-ring pairs normalizing and tempering treatment, provide a good organization for subsequent surface hardening; press drawings deformation of the half ring gear inspection after heat treatment.
2.5 Machining
First two and a half ring is made with high strength bolts connecting the ring as a whole, the overall process by drawing a circle Quannei Wai teeth and upper and lower end, and then drawing and machining milling process requirements.
2.6 Elimination of processing stress
The overall ring annealed to eliminate stress.
2.7 overall ring surface hardening
IF along the alveolar tooth surface induction hardening, hardness HRC50 ~ 55, effective hardened layer depth 3 ~ 5mm.
2.8 Final inspection
First, the detection frequency quenching, the hardness after tempering ring gear cogging meets the requirements of the drawings; secondly, to detect whether the maximum outer diameter larger size D6944 as the deformation 3mm, the mechanical correction required until qualified; Thirdly, tooth and fillet magnetic particle inspection, quality should meet two requirements GB/T9444-88 standard requirements; Finally, according to the drawings and technical requirements for final inspection.

Packaging & Shipping

It adopts the Export standard for delivery.

 Heavy Duty Cement Plant Dryer 40CrMo Rotating Gear Ring and spur gear manufacturer 1 
Our Services

CITIC Heavy Industries is your business partner in the After Market.

CITICIC is able to provide:








CITIC’s Field Service Engineers are trained specifically in the CITIC brand group products but are capable of undertaking the servicing of other OEM brands.

Our technicians are equipped with the most advanced technological diagnostic equipment available to trouble shoot your equipment to optimise performance and minimise down time.

CITICIC also has an extensive capability in supplying all you consumable and electrical/ mechanical spare part needs.

Quality Control

Physical & Chemical Identification Center
CITICIC owns a professional testing and metrology institute which provides advanced testing methods such as nondestructive 
testing, industrial chemical analysis, metallographic testing and analysis, mechanical testing, sample preparation, meter/length 
measurement, weighing apparatus verification, and weighman inspection. Our metrology institute has taken a leading role in China.

CITICIC owns nearly two hundred types of advanced testing equipment, nine different measurement standards and nearly twenty types of worldclass testing equipment which have been imported from international locations such as Germany, Japan, USA, 
UK and Belgium.

Contact Details
Luoyang Zhongtai Industrial Co., Ltd.

Contact Person: sales

Tel: +8618637916126

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