I, Bead cutting
1, Equipment selection
The glazing bead is cut by a bead cutting machine, which is mainly use for 45¡ã cutting, The bead for non-conventional and are window is generally cut on an any angle saw.
2, Bead cutting
Beads are prepared in accordance with actual dimension of the frame and sash¡¯s bead opening to ensure that the gap at corner joints comply with the requirements after assembly. The bead for rectangular frame and sash has a degree of 45¡ã¡À0.5¡ã. The angle for bead of non-conventional and arc windows is half of the angle formed by two adjacent structural members, with an allowance of ¡À0.5¡ã. The bead should be cut off a length of 3-4mm so that the window¡¯s bead interior groove¡¯s welding beading will not collide with the bead.

II Glass cutting
1, Glass type
Generally, UPVC windows and doors use float, tempered and doubling glass, with its thickness ranging from 3mm-6mm, 8mm, 10mm to 12mm. It could be fabricated into single-layer, common double-layer and hollow glass, etc. The hollow glass could be further divided into common and special gas type based on the gas inside the air cavity, or into double-layer or triple-layer void type based on product structure, or into common or special type based on product functions.
Common double-layer glass is fabricated by adding a partition strip between two pieces of glass. The hollow glass is fabricated with aluminum bar, hollow glue and desiccant.

2, Fabrication of hollow glass
(1) Glass selection
A hollow glass is fabricated by plate glass, laminated glass, tempered glass, heat absorbing glass, thermal radiating glass, embossed glass, etc. It is recommended to use colorless float glass or other energy-saving and safe glass. Do not use common plate glass.
(2) Glass fabrication
Please refer to the table beneath for technical requirements and dimensional standards during fabrication of hollow glass.
Shape and maximum dimension of commonly-used hollow glass as recommended-mm

Allowance Of Hollow Glass Length and Width-mm

Allowance Of Hollow Glass Thickness-mm

Allowance Of Hollow Glass Diagonal-mm

The glass is cleaned on the cleaner, Attentions paid during cleaning:
A, Inspect the water quality to guarantee its cleanness. Change timely the cleaning water and clean the filter. Make sure that the buoy works normally. Inspect the air filter regularly. Replace timely the old or damaged filter.
B, Check whether the water heater works normally and control the cleaning temperature at around 65¡ãC
C, Inspection the water flow at the sprinkler and brush. Keep the water flow steady. Don¡¯t let the pressure increase too high.
(4) Selection and adding of desiccant
The desiccant is filled on the desiccant-canning machine. It shall meet following technical requirement after filling.
A, The desiccant is stored in dry environment.
B, Leave a space for expansion and placing of inserted angles when adding desiccant, filling about 70%.
C, After the aluminum partition bar is formed into a frame, hang up the frame and keep it tidy and free from grease and dust.

The butyl glue on the partition frame is applied by the butyl glue applying machine. The butyl glue is the first sealing for the hollow glass and relates to a number of performance characteristics of windows and glass. The application of butyl glue should meet following specifications:
A, The thickness of single layer application is 0.75mm¡À0.05mm
B, The glue applied is uniform and continuous in depth and width without breaks or bubbles.
C, The joints should be treated reasonably and free from gaps.
D, Check that its interior is clean and distance between the partition frame and four sides of the glass are uniform when putting the glass together. After the glass is put together, use a roller to press even the glass with some fore.

The polysulfur glue is applied after the glass is put together, by double-ingredient glue applying machine or manually. After the glue is applied, make sure no insufficient or excessive glue. Keep the glass clean. Meanwhile, make sure that the desiccant and polysulfur glue are mixed in suitable proportion, The time that the hollow glass takes for drying depends on the atmospheric temperature.

3, Glass Cutting
The glass¡¯s cutting dimension should satisfy its installation depth of ¡Ý18mm. Inspect the glass quality before cutting and make sure that it is free from scratches and bubbles. Impact by external force exists no matter manual or machinery cutting. Hence, keep the atmospheric temperature above 15¡ãC. The glass having been cut should have neat edges without saw-tooth edges or notches. Edges grinding is recommended. Prevent the glass from cracking during fabrication, transportation or use.

III, Glass installation

1, The atmospheric temperature for glass installation is not less than 15¡ãC.
2, Keep the glass from direct contact with profiles during installation. Add glass block or pad at suitable positions inside the groove during glass installation.
3, Install first short and then long beads when installing the glazing beads. Use rubber hammer to knock the glazing bead. Don¡¯t use hard hammers such as wooden, hard plastic or metal ones.
The bead, one installed, should be fixed. The gap at the corner joints is 0.3-1mm. Use a whole piece of bead on any side and don¡¯t use broken beads.
4, A positioning device should be available when installing glazing bead to avoid that the side to be knocked is in suspension. It is recommended to fabricate an adjustable positioning frame with certain rigidity. Place the frame and sash that should be installed with beads inside the positioning frame and then knock on the beads.
5, When knocking on the glazing beads, knock in first the corner and then the middle, with a suitable force. The force direction is perpendicular with the profiles to be installed with beads. Don¡¯t knock slantingly towards the angle.

¢ô. Glass block
Glass block or gaskets must be filled between the glass and profile. The glass blocks are divided into two types: bearing and positioning blocks.
Use hard UPVC blocks as glass blocks, which are resistant to corrosion and don¡¯t deform. The glass blocks should be 1-2mm wider than the glass, about 100mm long and 3-4mm thick. The glass blocks are divided into two types: flat board or inserting-from-angle. Different types of windows and doors are filled with different glass blocks in both quantity and position. The glass blocks at lower part of the sliding window should be placed above the pulley. It is better to use glass blocks that are inserted at angles for casement windows. The installation of glass blocks for several kinds of windows and doors is shown in figure 1-26

>Hollow Glass Shutter