Composite pavement is two materials in one cut. The saw enters abrasive asphalt and then meets hard concrete underneath, and a blade bonded for either one alone will struggle with the other: an asphalt bond glazes in the concrete, and a concrete bond is torn apart by the asphalt above it. The MK Diamond MK-625W is bonded for the combination. This is the 18-inch wet cutting blade in the series, sized for walk-behind saws in the 8 to 20 horsepower range and intended for road, utility and parking lot crews cutting overlaid pavement.
Use cases
- Trenching and utility cuts through asphalt overlay on a concrete base
- Saw cutting patch boundaries for street and roadway repair
- Parking lot and access road repairs where the surface has been resurfaced over old concrete
- Municipal maintenance work where the pavement build up is unknown and may be composite
Why asphalt over concrete needs its own bond
Asphalt is soft and highly abrasive, so it wears a bond away quickly and calls for a hard bond that resists erosion. Cured concrete is hard and far less abrasive, so it calls for a softer bond that erodes fast enough to keep exposing fresh diamond. Those requirements pull in opposite directions, and a composite cut demands a bond formulated to survive both without failing in either. That is the whole reason a separate asphalt over concrete blade exists rather than simply using an asphalt blade.
Matching the blade to the saw
MK Diamond rates this blade for saws in the 8 to 20 horsepower range. Horsepower matters because a blade carrying a heavy diamond concentration needs the power to drive it. On an underpowered saw the blade will not cut at the rate it is capable of and the operator tends to push, which generates heat and wear rather than progress. Depth of cut is set by the saw rather than by the blade; an 18-inch blade on a walk-behind saw typically yields in the region of six to seven inches, with the exact figure fixed by the saw flange and guard.
Specifications
- MK Diamond part number 150815, MK-625W series
- 18-inch diameter
- 0.250-inch segment width
- 1-inch arbor
- 12 mm segment height
- Horsepower range 8 to 20 hp
- Wet cutting
Frequently asked questions
What does asphalt over concrete mean?
It describes composite pavement, where an asphalt surface course has been laid over an existing concrete slab or base. A cut through it passes through both materials, which is why the blade is bonded differently from a pure asphalt or pure concrete blade.
Does this blade require water?
Yes. The W designation marks it as a wet cutting blade, so the saw must supply continuous water to the blade while cutting.
What size saw does this blade suit?
MK Diamond rates the blade for walk-behind saws in the 8 to 20 horsepower range. Confirm that your saw accepts an 18-inch blade on a 1-inch arbor and is within that power range.
Can I use this blade on plain asphalt or plain concrete?
It will cut both, since it is bonded to survive both in the same pass. If all your work is one material, MK publishes dedicated asphalt and concrete series that are bonded specifically for it and will generally give better life and cutting rate in that single material.
How deep will an 18-inch blade cut?
Depth is determined by the saw, not the blade. An 18-inch blade on a walk-behind saw typically gives in the region of six to seven inches of depth. Check the depth rating published for your machine.
Discount Cleaning Products is an authorized MK Diamond dealer and supplies diamond blades, surface preparation equipment and jobsite consumables to contractors and facility maintenance teams across the United States, with US-based service and support.
