In steel rolling plants, roller chocks are vital components that support and align the work or backup rolls while housing the bearings that facilitate smooth rotation. These components must perform under extremely high loads and temperatures to ensure operational stability.

Key Functions:

• Force Transmission: Efficiently transferring rolling force from the rolls to the mill housing.
• Alignment: Maintaining precise alignment to ensure uniform product quality.
• Protection: Shielding sensitive bearings from contaminants.
• Maintenance: Enabling quick and efficient roll changes.

Operational Challenges: Chocks face significant stress factors, including high mechanical loads, heat-induced deformation, continuous wear and fatigue, vibration, and dynamic impact loads. Furthermore, difficulties in lubrication and sealing can lead to bearing damage. To survive these demanding environments, TSF chocks are engineered to combine immense strength, rigidity, and effective protection systems.

Case Study: Innovation for Mobarakeh Steel Company (MSC)

The Challenge (Pre-2013): Before 2013, the F5-F7 chocks for Mobarakeh Steel Company’s rolling mill lines were manufactured by machining ready-forged blocks. Due to the lack of a capable domestic foundry unit at the time, this method resulted in limited material selection options and significantly high final costs.

The TSF Solution: During technical visits to Mobarakeh Steel, TSF experts proposed a shift to the casting and machining method. Following subsequent visits by MSC rolling unit managers to TSF facilities and their approval of our quality standards, we initiated production.

Key Milestones:

• First in Iran: TSF successfully produced 24 sets of F5-F7 chocks using the casting method—the first time this was achieved domestically.
• Rigorous Testing: These parts underwent chemical analysis, mechanical property testing, and non-destructive testing (UT and PT) before final machining and delivery.
• Continued Success: Following the successful application of the initial batch, TSF has produced and delivered more than 500 Choks using the same proven method till now.

Material Science: FE G 80 and GS 42CrMo4 Steel

To meet the highly sensitive conditions of chock operation, TSF utilizes FE G 80 or GS42CrMo4 steel. This alloy relies on a precise combination of Nickel, Chromium, and Molybdenum.

Metallurgical Control:

• Melt Quality: We prioritize achieving a pristine melt by minimizing unwanted elements, specifically Phosphorus and Sulfur. Reducing these elements is critical to significantly increasing the toughness of the parts.
• Heat Treatment: We utilize advanced furnace equipment and experienced personnel to precisely determine and implement the heat treatment cycle. This ensures the material achieves the specific mechanical properties required for heavy-duty rolling.
• Verification: A test block is attached to each individual chock during production. This allows for direct control of mechanical properties and ensures strict compliance with standards.

Quality Assurance and Technology

Due to the operational sensitivity of roller chocks, TSF ensures that no defects exist beyond standard limits.

Engineering & Simulation Our Design and Technology Unit utilizes advanced simulation software to develop, control, and modify casting technology before production begins.

Non-Destructive Testing (NDT) Mandatory inspections are performed on all parts by TSF’s certified quality control and laboratory experts:

• Ultrasonic Testing (UT): To control and detect internal defects.
• Liquid Penetrant Testing (PT): To control and detect surface defects.