HS code: 44123900: Other upper and lower surface are made of softwood plywood sheet

This plywood belongs to class I/2:

Class l - has high water resistance, good boiling water resistance, the adhesive used is phenolic resin adhesive (PF), mainly used for outdoor;

Class II - water and moisture-proof plywood, the adhesive used is melamine-modified aldehyde resin adhesive (MUF), which can be used in high humidity conditions and outdoors;

Plywood used as concrete formwork has the following advantages:

(1) The board width is large, the dead weight is light, and the board surface is flat. It can not only reduce the installation workload, save on-site labor costs, but also reduce the cost of decoration of exposed concrete surfaces and the cost of grinding away joints;

(2) Large bearing capacity, especially good wear resistance after surface treatment, which can be reused many times;

(3) The material is light, the wood plywood is 18mm thick, and the weight per unit area is 50kg. The transportation, stacking, use and management of the template are more convenient;

(4) Good thermal insulation performance, can prevent the temperature from changing too fast, and the construction in winter is helpful for the thermal insulation of concrete;

(5 )sawing is convenient, easy to process into various shapes of templates;

(6) It is convenient to be bent and formed according to the needs of the project and used as a surface template.

(7) Ideal for fair-faced concrete formwork.

Precautions for use

(1) The plywood that has been treated with the board surface must be selected.

When the untreated plywood is used as a formwork, due to the bonding force between the cement and the wood on the interface between the plywood and the concrete during the hardening process of the concrete, the bonding between the board and the concrete is firmer, and the board is easy to be removed when demoulding. The surface wood fibers are torn, which affects the quality of the concrete surface. This phenomenon gradually aggravates with the increase in the number of times the plywood is used.

The plywood after being covered with film increases the durability of the board surface, has good demoulding performance, and has a smooth and smooth appearance. Overpass. Silos, chimneys and towers, etc.

(2) Plywood (also known as white board or plain board) without surface treatment should be treated before use.