Technical Profile-Fastening Bolt 200MG41.11.09.77

The Fastening Bolt 200MG41.11.09.77 is a high-strength specialized component engineered specifically for the grinding roller assembly of medium-speed coal pulverizers. It is primarily designed for the ZGM series, with precision adaptation for the ZGM123G model's roller component connections.

As the grinding roller assembly sustains the primary crushing pressure, these bolts must endure alternating loads, impact forces, and vibrational stress during rotation and pulverization. Consequently, the bolt is manufactured to meet rigorous standards for strength, hardness, and mechanical stability.

1. Key Technical Specifications

The bolt is fabricated from specialized high-strength alloy steel. Its mechanical properties are optimized to prevent fractures or deformations under the rated grinding pressure of the ZGM123G pulverizer.

2. Technical Features and Advantages

• Superior Material & Heat Treatment: Unlike standard industrial bolts, this component undergoes a specialized heat treatment process. This ensures high tensile strength while maintaining excellent fracture toughness, allowing it to withstand high-frequency vibrations and reduce the risk of fatigue failure.

• Precision Manufacturing & Compatibility: Designed strictly according to OEM standards, it ensures seamless integration with surrounding parts such as the Oil Seal Support Ring (20MG40.11.09.83) and Shaft Sleeve (20MG40.11.09.84). This precision prevents excessive assembly clearances that could lead to intensified equipment vibration.

• Enhanced Serviceability: The black oxide surface treatment improves corrosion resistance and provides necessary thread lubrication. This facilitates easier installation and removal during maintenance, effectively shortening equipment downtime.

3. Application Scenarios

The bolt is a critical "wear-and-tear" spare part used extensively in coal-fired power plants and large-scale cement plants utilizing ZGM123G pulverizers.

Routine Maintenance

Every 2,000 operating hours, the roller frame wear plates and fastening screws must be inspected. This includes verifying the torque of the 200MG41.11.09.77 bolts. Since high-frequency vibrations can cause torque decay, timely re-tightening is essential to prevent loosening, which could otherwise result in uneven wear of the roller/grinding ring or even roller displacement.

Overhaul and Disassembly

During major equipment overhauls or when vibration anomalies occur, the roller assembly is disassembled. According to maintenance protocols:

• Bolts showing thread wear, plastic deformation, or hardness degradation must be replaced immediately.

• New bolts must be used whenever roller tires (sleeves) or liners are replaced to ensure connection stability.

• Strict adherence to OEM torque specifications is mandatory during reassembly to ensure the hydraulic loading pressure is correctly transmitted through the roller assembly.

Safety Note: As a core connection node, the failure of this bolt can lead to catastrophic accidents, such as roller detachment. It is vital to use genuine parts that match the technical standards of the ZGM123G system.

HKZX-2026-01-08