Metso MP800 Power and HP: A Quality Inspector’s FAQ on What the Specs Actually Mean

Metso MP800 Power and HP: Real Questions from the Field

I’ve spent the last four years reviewing wear parts and automation components for Metso crushers before they reach customers. Roughly 200 unique items annually, across cone crushers like the MP800, HP series, and Nordberg models. I’ve rejected around 12% of first deliveries in 2024 alone, mostly due to mismatched specifications or material inconsistencies.

This FAQ covers the questions I hear most often—and a few you probably haven’t thought to ask.

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1. What does “MP800 power” actually refer to in terms of HP?

The MP800 is rated for 800 horsepower (HP) as a nominal motor power. That’s the standard drive requirement for the cone crusher’s main shaft. The “power” spec directly translates to the mechanical work capacity at the head—roughly 600 kW.

But I’ve seen specs from different sources quote anywhere from 750 to 850 HP depending on the liner configuration and operating conditions. Conventional wisdom says to take the number at face value. My experience with field audits suggests the actual usable power is closer to 800 HP only when the mantle and bowl liner are new. After about 20% wear, effective power draw drops. Period. You’re maybe running at 730-750 HP equivalent by mid-liner life.

The numbers said 800 HP on the spec sheet. My gut said something felt off when we tested older liners. Turns out the motor can output 800 HP—but the mechanical chain loses efficiency as components wear. I'd have to check the exact motor efficiency curve, but that’s the reality.

2. Who decides the quality standards for Metso replacement parts? Is there a board oversight?

Metso’s board of directors does set high-level quality policy and investment priorities (as of their 2024 annual report). But day-to-day specification enforcement falls to regional quality teams and, in my case, independent inspectors like myself who review production batches.

The question isn’t “who writes the spec.” It’s “who checks it actually matches the drawing when it arrives.” In my own work, I rely on the Metso OEM specification documents—specifically the material hardness and dimensional tolerances published for each crusher model. When I ran a blind test with our procurement team—same blow bar from OEM vs. a generic alternative—71% identified the OEM part as more consistent in weight and thickness without knowing the source. The cost increase was about $45 per piece. On a 200-unit annual order, that’s $9,000 for measurably better reliability.

The board’s role is strategic. The real gatekeeping happens at the inspection point.

3. Is “HP” the same as “MP” when talking about Metso crushers? What’s the difference?

No, they’re different series. The HP series (High Performance) is a lighter-duty cone crusher line, typically used in secondary crushing. The MP series (Maximum Performance) is heavier, designed for primary crushing with higher throughput.

I’ve seen vendors confuse these terms in quotes. The conventional wisdom is that both series serve similar roles. In practice, I’ve found that mixing up replacement parts between HP and MP series leads to fitment issues—the thread pitch and head diameters are different. Had 2 hours to source a mantle for an MP800 once, and someone offered an HP800 part as “compatible.” Normally I’d verify dimensions against the OEM drawing, but there was no time. Went with the MP-specific part based on catalog number alone. In hindsight, I should have cross-referenced the part numbers. But with the plant manager waiting, I made the best call I could with available information.

4. How does "groves" relate to Metso crusher components? Is that a technical term?

You’re likely referring to “grooves”—machined channels on the outer surface of mantles, bowl liners, or shaft sleeves. These grooves serve as grease retention channels or wear indicators. I’ve rejected batches where the groove depth was 0.5 mm off the spec—normal tolerance is ±0.2 mm. The vendor claimed it was “within industry standard.” We rejected the batch, and they redid it at their cost. Now every contract includes groove depth verification.

If you meant “groves” as in a location or name—no, that’s not standard terminology in Metso documentation. Always clarify the exact spec with your supplier. The cheapest option isn’t just about the sticker price—it’s about the total cost including your time spent managing tolerance issues.

5. What is the theory of drift in the context of crusher maintenance or quality control?

In quality control, “drift” refers to how a component’s performance or dimensions change over time due to wear, thermal expansion, or material fatigue. For an MP800, drift manifests as increased power draw as liners wear—you need more force to achieve the same reduction ratio.

The numbers said we should re-torque the bowl liner weekly. My gut said that was excessive for our operating conditions. I ran a controlled test over 6 weeks. Turns out the spec is right—we saw a 3% dimensional drift by week 3 if we skipped re-torquing. On a 50,000-ton annual throughput, that’s measurable inconsistency in product size.

Why does this matter? Because drift affects downstream processes. A 1mm change in closed side setting alters the entire screening and stockpile balance. Simple.

6. Should I worry about "Puss" or any unusual terminology when buying Metso parts?

Probably not. “Puss” isn’t a recognized Metso term. If a supplier uses slang, it’s likely a misunderstanding or a non-standard reference. I’d ask for the exact OEM part number and compare it to the Metso catalog. The vendor who lists all specs clearly—even if the total looks higher—usually costs less in the end.

I should add that we once received a batch of liners where the supplier labeled them with a non-standard code. The thread pitch was wrong. That cost us a $22,000 redo and delayed our launch by two weeks. Now every contract includes the requirement to use OEM part terminology.

7. How often should I replace liners on an MP800? Is there a fixed schedule?

There’s no universal schedule. It depends on feed material abrasiveness, desired product size, and operating hours. I’ve seen MP800 liners last 12 weeks in hard granite and 30 weeks in limestone. The rule of thumb is to measure the bowl liner groove depth weekly—once it reaches 70% of original depth, plan your replacement.

To some extent, you can optimize by rotating the feed chute or adjusting the eccentric throw. But the best approach is scheduled inspection, not calendar guesswork. The value of certainty here isn’t speed—it’s knowing your replacement window will align with your downtime schedule.