KPMBOLT super nuts, subjected to 100% full-process inspection, provide heavy-duty anti-loosening and long-term stable fastening for end covers, bearings and hollow shafts of ball mills, vertical mills and rod mills.

Ball mills, vertical mills, and rod mills are core heavy-duty equipment in the mining, building materials, and metallurgy industries. Key components such as end covers, hollow shafts, bearing housings, and main flanges are subjected to super-heavy loads, continuous vibrations, alternating stresses, and material impacts. Traditional nuts tend to loosen under long-term heavy loads, causing leakage, displacement, vibration, and seal failure—issues that lead to equipment downtime, high costs, and low efficiency. German KPMBOLT Super Nuts, drawing on nearly 200 years of fastening technology from JUNGEBLODT, adopt a multi-jackbolt structure and strict full-process quality control…Quality control. They are specifically designed for heavy – load and vibration conditions, emerging as the most reliable fastening solution for milling equipment.

KPMBOLT consists of a nut body, jackbolts, and thrust washers. All products are manufactured in accordance with the Manufacturing and Inspection Process Plan (MPP). The nut body is crafted from high – strength alloy steel accompanied by a material certificate, belonging to the same batch and heat number. The chemical composition has been verified by a spectrometer, complying with GB/T 3077. After heat treatment to a hardness range of HRC 30–36, 100% of the products undergo hardness testing. The grain size is ≥5 grade, and 100% are subjected to ultrasonic testing (UT) in line with EN 10308 Level 4.

The jackbolts are made of higher – grade steel with a hardness of HRC 48–54. 100% of them are hardness – tested, and the yield strength is ≥1500 MPa. 100% are subjected to magnetic particle testing (MT) according to EN 10228 – 1 Level 4. The washers have a hardness of HRC 40–44, featuring high precision and being free of defects. The pure axial preload guarantees uniform force distribution and prevents loosening.

These products are extensively applied in mill end covers, hollow shafts, bearing housings, main flanges, and grinding tables. With sizes ranging from M30 to M150, they can directly replace the original nuts and are easy to install. The failure rate is reduced by over 90%, the operation time is increased by 40%.The cost is reduced by over 50%. Holding a Chinese patent and featuring fully traceable quality, KPMBOLT meets the standards of heavy milling equipment. With the development of the industry, KPMBOLT offers safer, more reliable, and more economical fastening solutions for milling equipment, assisting enterprises in cost reduction and efficiency improvement.

References:

• GB/T 3077;
• KPMBOLT MPP documents;
• JUNGEBLODT technical data;
• Mining Machinery.