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by Jim Schreiner

Regardless of the type of equipment used on the job site, the importance of routine inspections and proper maintenance are paramount to maximizing uptime and production output. If the plant isn’t running, it isn’t producing, and lost production is expensive or impossible to make up. Planning “maintenance time” and using it effectively is how premier producers consistently achieve higher levels of uptime availability. They anticipate maintenance and plan for predictable uptime. To say it best: More uptime translates into lower production costs.

Even though impact crushers have been around a long time, their use has expanded significantly in the last 30 years, primarily due to advances in wear parts metallurgy. On the plus side, impact crushers are capable of high throughput capacity, high reduction ratios, and are relatively forgiving to fluctuating feed materials. On the negative side, they are susceptible to high consumption of wear parts and high maintenance downtime. When crushing abrasive materials, wear parts cost and cost of downtime can become prohibitive, even with advanced wear parts technology. The first step to predictable uptime and low operating costs is applying the machine correctly.

Successful operators plan their run time and maintenance downtime and use it effectively. They make sure that when that impact crusher starts up, it is going to go the distance to the next scheduled maintenance shift. They anticipate (track and log) wear parts consumption and have spare parts available on site. They constantly inspect the machine to look for developing problems and implement corrective actions before a crisis exists.

It is a good idea to always have blow bars, apron liners, and replacement hardware on hand for that unexpected issue that can appear. If, during normal maintenance, a cracked part is discovered, replace it immediately. Waiting for a dealer to deliver parts, or being told to run the machine in its compromised condition, is too high of a price to pay. Keep critical parts on hand.

Planning for maintenance begins before purchase and installation of the crusher. Selecting crusher features that allow safe, easy, and quick maintenance means the crew is far more likely to perform maintenance and finish tasks on time. Consider the following recommendations:

1. The crusher should open easily (hydraulics) and allow for crane access and a vertical lift of heavy castings. Safe lifting points should be built into castings. Hardware should be simple and easily accessible from safe working points.

2. Look for a design that uses common castings (side liners, blow bars, apron liners) throughout the crusher. This reduces parts inventory requirements and allows interchangeable parts to be flipped or relocated to optimize utilization.