"Seo" system

Superficial protection

There are several bar surface protection systems available and it belongs to the customer to indicate the process to be applied in each case. However, the space structure protection system most currently used on the Spanish market consists in painting by electrostatic application of polyester resin powder, to a minimum layer thickness of 70 microns, followed by oven-curing. Prior to this protection process, a surface preparation treatment must be applied and it comprises at least degreasing and phosphating when there is no track of oxidation and mechanical cleaning by brushing and even Shotblasting should the bars be oxidised. Shotblasting is applicable, even though there is no oxidation, in order to improve the adhesion of the paint layer whenever this would be advisable for special cases.

Process

The structure shall receive a high protection surface treatment enabling us to guarantee its painting against red rust.

This treatment includes the following processes:

The bars are machined from mass production tubular profiles and subsequently undergo the following operations:

- Scouring
- Washing
- Electrogalvanizing - 20 microns (if fitting)
- Drying
 
The painting process that follows consists in:

1.- Surface Preparation.-

- Spray acid degreasing
- Rinsing
- Spray amorphous ferric phosphating
- Spray amorphous ferric rinsing
- Spray chromic passivating
- Spray chromic rinsing
- Spray washing with deionized water
- Air drying at 100o C.

2.- Painting

- Electrostatic polyester powder with a minimum coating thickness of 70 m.

3.- Curing

- Air jet oven 210o C. during 20 minutes. Room temperature.

The entire process is performed in a chain-work like and continuous way.

The indicated painting process permits to obtain a surface of considerable scratching as well as impact mechanical resistance, having an attractive lacquer-like finish and a quality far superior to that of other painting processes.

As for spherical joints, similar oven-curing treatments can only be applied in the low diameter range. In the high diameter range (Æ210 and Æ250), due to the greater thickness, these treatments are problematic and are normally replaced by shotblasting preparation, primer coating, and two epoxy or chlorinated rubber paint finish coats.

In any case, the space frame surface treatment is not ingerent to LANIK system and must be agreed upon with the Customer in each case.