'Faster, more powerful and therefore cheaper'

Pulverizers lasting over 25 years, even in daily production process

"The gems within our delivery program," owner Arthur Polak of DemTech calls the NPK concrete crushers. Hence, for Bouwmat, he is happy to explain what the Japanese-made crushers are capable of. "They are high quality and also make a measurable difference." 

According to Polak, this is in the high production, suitability for smaller cranes, reduced fuel consumption and durability due to the tremendously long service life. 

NPK concrete crushers are available in two series: the rigid G series and the rotating U series, which may also be used for primary demolition processes. The U series runs up to a 5-ton crusher. "Why not bigger? Because even heavier doesn't outweigh the efficiency you want to make in terms of fuel consumption," Polak says. "Very cool to have the biggest one, but you then consume more fuel than the yields." 

Power Booster

The reason for that high efficiency is the so-called Power Booster, a pressure booster that has been built into NPK pulverizers since 1978. "With that you work twice as fast and you can increase the pressure up to three times," Polak explains. "That pressure booster on the cylinder is designed so that it automatically kicks in as soon as the pulverizer encounters back pressure. This makes the concrete pulverizer, with a relatively low oil flow, much faster and more powerful than pulverizers without a pressure booster, while other hydraulic functions of the excavators remain unaffected."

This design also makes the pulverizer much more compact, lighter in weight and user-friendly. According to Polak, you can do the same work with an NPK pulverizer on a 25-ton crane as with another brand on a 35-ton crane. "A 35-tonner with an NPK G-28 pulverizer or a 22-tonner with a G-18 is the ideal combination as far as we are concerned. In terms of efficiency and cost cannot be surpassed." 

Because of the Power Booster, NPK can work with smaller cylinders, which in turn results in a very low adjustment of the crane. "We only require between 200 and 250 l/min at 260/280 bar working pressure. As a result, a crane consumes considerably less fuel and you can get by with a smaller crane. I once calculated that with a full tank of fuel with the NPK Power Booster, you can get 4.81 additional hours of operation and crush 255 additional tons of concrete."

Long lifespan

NPK is also distinguished by its extremely long service life. "I think as much as a factor of two to three compared to other brands," Polak says. "I know of examples of pulverizers that have lasted more than 25 years. With the right maintenance intervals, they reach 25,000 operating hours anyway." In this, DemTech has a maintenance program, which easily calculates costs over the entire life of the pulverizer.

Because of the power, efficiency and longevity, Polak says it is quite easy to calculate the annual costs and returns of the Japanese pulverizers. "Because you can get by with a smaller crane and save considerably on fuel, the initial investment is considerably lower. That's really the added value of our product." Should anyone doubt Polak's calculation, he is more than happy to measure and calculate together.