The production of double-glazed windows, as a rule, is fully automated or carried out using a remote control.
At the stage of preparation, the glass and the spacer frame are cut according to the order conditions, the edge is processed and the glass washed.
Glass quality control is required: the glass must be evenly cut, clean, without chips or cracks.
At the same stage, a spacer (contour) is formed, most often aluminum or steel, hollow inside and with perforations. The task of the dehumidifier, which is poured into the frame, is to prevent the appearance of condensation, i.e. absorb any excess moisture from the inter-glass space.
Insulating glass assembly stage. This is also the first stage of sealing: a butyl cord is applied to the distance contour on both sides and glass is glued. After crimping, squeezing the glass unit, the butyl seam becomes as thin and dense as possible.
The chamber is filled with dried rarefied air or inert gas.
The next stage is secondary sealing: thiokol, the most popular in quality and price two-component polysulfide sealant, is applied to the outer contour of the glass unit, although it can be a one-component hot melt sealant and polyurethane or silicone masses.
The final stage is visual quality control: how did the sealant layer lay down, whether there is any dust or debris inside the air chamber. The glass unit must be transparent, without distortion, cracks, chips, dirt, etc.
After the hermetic material has cured, the glass units are placed in a special drying device.
Already finished products are checked for compliance with dimensions, tightness, resistance to heat transfer, control of defects in the appearance of glass.
All these norms and requirements are defined in GOST 24866-99. All the necessary test methods for determining the dew point, dimensional accuracy, strength, gas permeability of glass units, etc. are indicated here.