Graco Inc.

Painting heating panels with ProMix™ 2KE and Pro XS™ Auto electrostatic gun




Betherma, located in Oss, the Netherlands, is a company dedicated to the development, production and sale of heat convectors and radiators. The heat convectors, made in aluminium and steel, are painted via a powder coating application line; the special ceiling panels, due to their large size, are sprayed with liquid paint via a specific painting line that uses reciprocators and automatic electrostatic guns.

The heating ceiling panels are designed to heat spaces of between 3 and 30 meters high. This makes them suitable for warehouses and logistic centres, production halls, display and sales rooms, car/truck/bus dealerships, sport and multi-purpose rooms, aircraft hangars, shipyards and railway workshops.

These efficient heating panels are placed in ceilings. With a thickness of 1 mm, they support up to 10 bar of heating fluid pressure and are insulated on their upper side with mineral fibre 40 mm thick. The panels are mainly offered in two colours (white or pearl grey) painted with two component paints. Other secondary colours are also available on demand, so the painting line includes extra pumps to handle optional colours.

Due to the large size of the radiators (1 meter high by 3-6 meters long), the paint process has to be the simplest possible to reduce to the maximum the handling of these parts. This is why the painting process includes only one final 2K coating applied directly on the metal without a primer. The average production is 60 panels per day. The panels are cleaned, fixed in the transporter and paint is applied directly in the spray booth.


To manage the 2K paints in the simplest way, Paint It selected the Graco ProMix 2KE for its simplicity of use and programming. The dosing technology used for the set-up is sequential dosing (ProMix 2KE can work in either sequential dosing or dynamic dosing). The ProMix 2KE with 3 colours can handle 3 additional 2 component colours. One extra pump is available for auxiliary colours. The ProMix 2KE feeds the automatic Graco Pro XS4 AA gun mounted on the reciprocator.

The 2K paint from Zandlever Coatings (Polyfinish) is supplied in 200L drums and 54 litre pails. The mix ratio is 9:1. The ProMix 2KE (meter version) allows the use of supply pumps (colours catalyst solvent) that Betherma originally had (Böllhoff Merkur pumps). The new ProMix 2KE replaces an old Graco ProMix I proportioner and upgrades the installation to manage the main 3 colours.


End User:
Betherma B.V.
Industry Market Sector
Heating systems

2K coating application on aluminium ceiling heating panels, with 2K equipment and electrostatic automatic gun
Material specifications
Producer: Zandlever Coatings BV
Name of material: Polyfinish MU-DL
Typical Properties: 2K PU, SB, 9:1 mix ratio

Graco Equipment:

  • 1 x ProMix 2KE 24F087 (3C, IS)
  • 5 x Böllhoff Merkur pumps
  • 1 x Pro XS4 AA Auto gun

The proportioner feeds a Graco automatic electrostatic gun mounted on a reciprocator.

Graco Distributor Details:
PAINT IT, application company
Max Planckstraat 4A
6716 BE EDE
The Netherlands
Fax: 31 318643042
Phone: 31 318643260