Medium-Speed Pulverizer Composite Grinding Roller Sleeve 20MG53.11.09.99

In coal-fired power plants, the roller sleeves of medium-speed coal pulverizers frequently suffer from premature wear (e.g., standard sleeves requiring replacement after only 4,000 operating hours) due to intense grinding and coal flow erosion. This lifespan significantly falls short of the design value, directly impacting the stability and availability of the milling system.

As your professional power station spare parts supplier, our Medium-Speed Mill Dual-Metal Composite Roller Sleeve, model 20MG53.11.09.99-DH, is specifically engineered for ZGM-type pulverizers. It is ideal for abrasive coal types with high ash content, high silica content, and a high abrasion index. We offer a 48hour emergency response to support plant overhauls, reduce maintenance costs, and extend unit availability.

I. Root Causes of Abnormal Roller Sleeve Wear: 3 Key Factors to Address

Based on the DL/T 838-2017 "Guideline for Overhaul of Coal-Fired Power Plant Equipment" and operational data from over 30 power plants, abnormal roller sleeve wear in medium-speed mills primarily stems from the following three issues, which the 20MG53.11.09.99-DH is designed to eliminate:

1. Mismatch Between Coal Quality and Material: When the coal's value exceeds 3.5 (severe abrasion level), the wear layer of traditional high-chrome cast iron sleeves can rapidly spall. This problem is particularly pronounced in ZGM-type pulverizers due to their high grinding force.
2. Failure to Remove Hard Impurities: Inefficient iron removal systems or large screen mesh sizes in the coal conveying system allow rocks and tramp metal to enter the grinding zone, causing local impact wear and cracking of the roller sleeve.
3. Deviation from Design Operating Parameters: Prolonged high-load operation and excessive primary air flow accelerate the erosion of the roller surface by the pulverized coal stream, thus drastically shortening sleeve life.

II. 20MG53.11.09.99-DH Technical Solution: Dual-Metal Composite + High Wear Layer

The 20MG53.11.09.99-DH composite roller sleeve addresses these issues through material upgrades and process optimization. Details are provided below, covering core parameters and manufacturing process:

1. Core Technical Parameters (Adapted for High Value Coals)

2. Dual-Metal Composite Casting Process: Combining Wear Resistance and Impact Toughness

The 20MG53.11.09.99-DH utilizes a "Wear Layer + Matrix" dual-metal composite casting process:

• Wear Layer: Centrifugal casting technology ensures a uniform distribution of the Ni-Cr-Mo-V alloy
• Matrix: QT600 Ductile Iron is metallurgically bonded to the wear layer, achieving a bonding strength

III. Application Value: Power Plant Case Studies Confirming Longevity

The 20MG53.11.09.99-DH medium-speed mill composite roller sleeve has been successfully implemented in ZGM-type pulverizers across multiple 600MW and 350MW units.

Additional ZGM Series Pulverizer Products We Supply: