Grit Blasting Services

Angular steel grit cuts a sharp, deep anchor profile into steel.

Request a Blasting Quote Share a Drawing on WhatsApp
  • Steel grit, G14 and G16
  • Sa 2½ to Sa 3
  • Sharp anchor profile
Two enclosed blasting booths with orange frames in a bright factory hall, with a large casting on a rail trolley at the open booth

Why Thermal Spray Needs a Grit Profile

A thermal spray coating holds to steel mechanically. Molten zinc or aluminium droplets flatten into the peaks and valleys of the blasted surface and lock there as they cool. The sharper and cleaner the profile, the stronger the bond.

Angular steel grit fractures as it strikes the surface and cuts into the steel, leaving the jagged anchor pattern to which metal spray adheres best.

We blast with graded steel grit, including G14 and G16, and verify the profile with a surface profile gauge before any coating is applied.

Blast cleanliness reference chart: three starting conditions of rusted steel, each shown blasted to brush-off, commercial, near-white and white metal, beside a table of equivalent SSPC, NACE, SIS and ISO grades
Thermal spray requires the bottom two rows: near-white metal (Sa 2½) for zinc, and white metal (Sa 3) for aluminium in aggressive service.

When Grit Blasting Is Appropriate

Before Zinc or Aluminium Metallizing

Thermal spray zinc and aluminium require a clean, angular profile to bond to. Grit blasting to Sa 2½ or Sa 3 provides it.

Before Metallizing Worn Parts

Build-up on worn shafts and journals depends on a sharp, clean profile for adhesion.

High-Build Paint Systems

Thick epoxy and similar systems require a deeper profile than conventional paints in order to remain bonded.

Pitted or Heavily Rusted Steel

Angular grit removes pitted rust and tight scale efficiently.

Castings and Heavy Fabrications

Burnt-on moulding sand, scale and rust are removed from castings, machine-tool beds and fabricated frames, leaving an even surface for primer and paint.

Specification

Abrasive
Steel grit, including grades G14 and G16; copper slag and aluminium oxide as the project requires
Cleanliness
ISO 8501-1 Sa 2½, or Sa 3 for thermal spray aluminium
Equivalent grades
SSPC-SP 10 / NACE No. 2 (Sa 2½) · SSPC-SP 5 / NACE No. 1 (Sa 3)
Profile
Sharp, angular anchor profile; depth set by the coating specification
Profile check
Surface profile gauge, recorded before coating
Where
At our facilities in Bengaluru or at your site
Time to coat
Thermal spray applied within hours of blasting

Our Grit Blasting Procedure

Diagram in four stages: a large fabrication is degreased and masked, grit blasted inside a walk-in blast room, its surface profile is measured, and it is metal sprayed
Why It MattersAngular grit cuts a sharp profile into the steel. That profile is what holds a thermal spray coating in place. Illustrative diagram.

  1. Degrease and Mask

    Oil and grease are removed first, because blasting would otherwise drive them into the surface. Areas that must remain untouched are masked.

  2. Blast

    The steel is blasted with graded grit until it reaches the specified grade across the entire surface.

  3. Measure

    Cleanliness is checked against ISO 8501-1 and the profile is measured with a gauge.

  4. Coat

    Metal spray or primer is applied on the same day, while the surface is still clean and active.

Applications

Grit blasting is the preparation behind our thermal spray zinc, aluminium and advanced coatings, and for primer and paint on castings and fabrications.

An operator abrasive blasting a large rotary kiln shell section on site
  • Steel before zinc and aluminium metallizing
  • Chimneys, ducts and kiln shells
  • Storage tanks and vessels
  • Machine-tool castings, beds and fabricated frames
  • Shafts, rolls and valves before wear coatings
  • Structural steel for high-build paint

Frequently Asked Questions

What profile depth do you blast to?
We blast to the depth stated in your coating specification. Thermal spray and high-build coatings require a deeper profile than conventional paint, and we verify it with a surface profile gauge before coating.
What are G14 and G16?
They are size grades of steel grit. G14 is the coarser of the two and cuts a deeper profile, while G16 gives a slightly finer and more even one. We select the grade for the coating that follows.
Can grit blasting be carried out at our site?
Yes. Grit blasting is carried out at our facilities in Bengaluru or at your site, and our teams travel with their own compressors, blast hoppers and hoses.
Which abrasives do you use?
We use steel grit, copper slag and aluminium oxide. The abrasive is selected according to the steel, the profile required and the coating that follows.
Do you offer shot blasting?
Castings and fabrications are blasted with steel grit, which removes scale, rust and foundry sand and leaves the sharp profile that primer, paint and metal spray need. Please share the parts and the coating that follows, and we will confirm the method.

Related Services

Abrasive blasting

Abrasive blasting to Sa 2½ in preparation for coating

Thermal spray aluminium

Protection for high-temperature, marine and chimney service

Aluminium oxide blasting

Clean, hard abrasive for stainless steel and alloys

Send a Drawing for a Blasting Quote

Share the drawing or photographs, the present condition of the steel and the grade you need, such as Sa 2½. One of our engineers will reply with the method and a quotation.

Call+91 96861 11973 WhatsAppPhotographs and drawings Emailthermalspray@mythrimetallizing.net
  • Reply within one working day
  • Drawings kept confidential
  • Email acknowledgement

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