What Causes High Wear on Impact Crusher Blow Bars
For impact crusher operators in South Africa and Australia, high blow bar wear is a major operating cost. Understanding what causes high wear on impact crusher blow bars helps you select the right alloy, adjust operating parameters, and extend bar life. The Type I impact crusher is widely used for secondary and tertiary crushing of hard rock, but several factors can accelerate blow bar consumption. Below we explain the most common causes and practical solutions, based on OCP Mechanical Company’s 40 years of experience.
1. Abrasive Feed Material
The number one answer to what causes high wear on impact crusher blow bars is the abrasiveness of the feed material. Rocks with high silica content (e.g., granite, basalt, quartzite, and iron ore) act like sandpaper on blow bars. When processing such materials, standard chrome iron (Cr20%) blow bars may last only 50‑100 hours. Upgrading to Cr26% or martensitic steel can extend life by 50‑100%.
Note: Product data are constantly updated; for the latest blow bar alloy recommendations, please contact our online customer service.
Many quarries in Western Australia and Limpopo have switched to Cr26% blow bars for processing dolerite and granite, reducing annual blow bar costs by 30‑40%.
2. Incorrect Blow Bar Alloy for the Application
Another common factor in what causes high wear on impact crusher blow bars is using an alloy mismatch. For soft limestone, Cr20% may be cost‑effective. For hard, abrasive rock, a higher‑alloy bar (Cr26%, martensitic, or ceramic‑embedded) is necessary. Also, some blow bars are designed for high impact resistance (martensitic) while others excel in abrasive wear (high chrome). Choosing the wrong type leads to premature failure.
OCP offers a full range of blow bar alloys for Type I impact crushers. Our engineers can recommend the optimal material based on your feed rock’s abrasion index and silica content.
3. Improper Crusher Settings and Feeding
Operating conditions play a major role in what causes high wear on impact crusher blow bars. Key issues include:
Low rotor speed – Running below recommended speed (e.g., 400 rpm instead of 650 rpm) reduces impact energy, causing blow bars to “push” rather than “strike” the rock, leading to accelerated wear.
Excessive feed size – Feeding material larger than the crusher’s maximum rated size (e.g., 150 mm into a 100 mm crusher) causes severe stress on the blow bars.
Uneven feed distribution – Feeding only one side of the rotor causes localized wear, reducing bar life by 30‑50%.
High recirculating load – Returning too much oversize to the crusher increases the number of impacts per bar, accelerating wear.
To mitigate, use a VFD to maintain optimal rotor speed, install a vibrating feeder for even distribution, and screen out oversized feed.
The above values are for illustration only. OCP continuously improves its products. Contact our online team for the most current data sheet.
4. Lack of Regular Rotation or Replacement
A simple but often overlooked reason in what causes high wear on impact crusher blow bars is not rotating or replacing bars at the right time. Many blow bars are reversible or can be turned end‑for‑end to distribute wear. If you run bars until they are completely worn on one side, the remaining material may crack or break, causing damage to the rotor. Follow a scheduled rotation plan (e.g., every 100‑200 hours) and measure wear profiles regularly.
OCP’s technical team provides wear tracking templates and online support for blow bar management. As a direct‑selling manufacturer, we supply factory‑priced blow bars with local stock in South Africa and Australia for fast delivery.
Why OCP Is Your Partner for Impact Crusher Wear Parts
Understanding what causes high wear on impact crusher blow bars allows you to take corrective action. OCP Mechanical Company has over 40 years of history in impact crusher technology. We offer:
Free pre‑sale feed analysis to recommend the optimal blow bar alloy.
Customized blow bar rotation schedules and inventory planning.
24/7 online technical support for troubleshooting and replacement guidance.
For a no‑obligation consultation and personalized advice on what causes high wear on impact crusher blow bars for your operation, simply click the live chat icon on this page. Our online customer service team is available 24 hours a day, 7 days a week, to answer your technical questions, provide free recommendations, and help you lower your cost per ton.
