Common FAQs on Improving Roller Wear Resistance of Roll Crushers in Brick Plants

Q1: What are the wear pain points of ordinary cast steel rollers?

A: Ordinary cast steel rollers (e.g., ZG35) have low hardness (< HRC 18) and are prone to grooving when encountering hard lumps in clay. For example, at a domestic brick plant, a pair of new rollers lasted only about half a year, requiring replacement or turning every 5–7 million bricks produced, resulting in high steel consumption and poor economic performance.

Q2: What is the most effective technical method to improve roller wear resistance?

A: The submerged arc automatic surfacing welding method. Turn a 7–14 mm groove on the old roller, and fill it with 30CrMnSi alloy welding wire and 102 ceramic flux. After surfacing, the surface metal becomes 30CrMo2SiMn with a bainite + martensite structure, reaching a hardness of about HRC 42.

Q3: How much can the service life of rollers be extended after surfacing repair?

A: Significantly. Ordinary cast steel rollers wore 6 mm after 23 days (producing 3 million bricks); surfaced rollers operated for 125 days (producing over 16 million bricks) with a maximum groove depth of only 7 mm. The service life of surfaced rollers is 2.5 to 5.5 times that of ordinary cast steel rollers.

Q4: What are the economic benefits of surfacing repair?

A: Rollers can be repeatedly surfaced and reused, offering even greater long‑term benefits.

Q5: What are the key techniques for surfacing construction?

A: The key is to ensure the number of surfacing layers. For the first surfacing, it is recommended to turn a 10–14 mm deep groove to guarantee at least three layers on the working surface. Because the first and second layers are diluted by the base metal, their wear resistance is lower than that of the third layer. The thicker the surfacing layer, the higher the wear resistance. At the same time, the weld layer must have sufficient toughness to resist impact from hard lumps.

Q6: How does the base metal material affect the surfacing result?

A: Significantly. Ordinary cast steel ZG35 has a loose structure and is prone to dents under the weld layer when encountering hard lumps. Material selection recommendations: forged steel is the first choice – dense structure and best support; manganese steel is the second choice – good toughness and impact resistance; if cast steel is used, at least ZG45 or higher grade is required.

Q7: What additional production advantages can surfaced rollers bring?

A: (1) Improved equipment utilization – rollers can be repeatedly surfaced, reducing replacement frequency; (2) Stable product quality – maintaining the process dimension of roll gap over long periods ensures consistent crushing and mixing quality; (3) Reduced maintenance workload; (4) Revitalization of scrap assets – a large number of previously scrapped rollers can be put back into use.