Diamond selection

Determining the hardness of concrete

All concrete may feel hard (particularly if you fall over on it), so what do we mean when we talk about hard, medium and soft concrete?

All concretes are measured by their compressive strength and depending on which part of the world you are from, different compressive strength indices (e.g. PSi & MPa). Generally speaking, the higher the com- pressive strength rating, the harder the concrete and therefore, the harder it will be to grind.

However, other factors beside compressive strength ratings determine how hard the floor will be, and therefore, the correct diamond selection. Since grind- ing normally only deals with the surface of the concrete (top 5mm or 1/4 inch), often the way the concrete floor has been finished or the condition of the surface will have a greater bearing on what type of diamond to select, rather than the compressive strength rating of the concrete.

SURFACE FACTORS TO CONSIDER WHEN MAK-

ING A DIAMOND SELECTION

Generally speaking, if a concrete surface is very smooth (i.e. Most likely it has been heavily trowelled/ helicoptered), the concrete will behave as if it has a high compressive strength and therefore, require a soft bond segment.

Accordingly, if a concrete surface is coarse/aggressive (e.g. rain-damaged, shot blasted, scarified, exposed aggregate e.t.c.), the concrete will behave as if it has a low compressive strength and therefore, require a hard bond segment.

Surface coatings/contaminants (e.g. Epoxy coatings, ceramic tile adhesives, levelling compounds/screeds) will often have a larger bearing on what diamond to se- lect, than will the compressive strength of the concrete.

As a general rule, when grinding a concrete slab for the first time and you are unsure about its hardness, always begin with harder bond diamonds under the machine. This will ensure the least amount of wear on the diamond segments. If a hard diamond segment is not suited to the application, all it has cost is a little amount of time without wearing out the diamonds.

If performed the other way around (i.e. a soft segment is used to begin with) and the concrete is soft or pos- sesses an abrasive surface or surface contaminant, it is quite possible to wear-out a considerable amount of diamond in very short period of time.

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Husqvarna PG530 manuel dutilisation Determining the hardness of concrete
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PG530 specifications

The Husqvarna PG530 is a powerful and versatile floor grinding machine designed for professional contractors and heavy-duty applications. This equipment is ideal for preparing and finishing various types of surfaces, including concrete, terrazzo, and natural stone. Built with advanced technologies and rugged construction, the PG530 stands out in the market for its reliability and performance.

One of the key features of the Husqvarna PG530 is its unique three-disc design, which provides efficient grinding performance. The three grinding heads allow for better distribution of weight and improved balance, ensuring an even grind across the floor. With a wide grinding width of 21 inches, the PG530 can cover large surface areas quickly, making it an efficient choice for both small projects and larger commercial jobs.

The machine is powered by a robust 15 HP motor, delivering ample power to tackle tough grinding tasks. It also features adjustable grinding pressure, allowing users to optimize the pressure according to the specific requirements of the job. This adaptability makes the PG530 suitable for a wide range of applications, from light surface preparation to heavy-duty grinding and polishing.

Additionally, the PG530 is equipped with Husqvarna's patented Dual Drive Technology. This innovative system provides independent speed control for both the grinding heads and the machine's forward movement. This capability allows operators to adjust the speed of the grinding discs while controlling the speed of the machine itself, resulting in enhanced flexibility and control during operation.

The machine is designed with user comfort in mind. Its ergonomic handle and adjustable working height make it easy to operate for extended periods without causing fatigue. The PG530 is also fitted with an integrated dust collection system, helping to maintain a clean working environment by minimizing dust and debris. This feature is essential for safety and compliance with health regulations.

In terms of usability, the PG530 is easy to transport and set up, making it a practical choice for contractors on the go. Its compact footprint ensures that it can maneuver in tight spaces, while the folding handle allows for easy storage.

Overall, the Husqvarna PG530 combines powerful performance, innovative technology, and user-friendly design to meet the demands of flooring professionals. Whether for surface preparation, grinding, or polishing, the PG530 is a reliable tool that enhances productivity and delivers superior results.
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