DONGHA handle to existing product and other all trades for everything.
Such as technology and manpower service.


Engineering Plastics (Polycarbonate)

Engineering Plastics is a high-performance plastic suitable for structural and mechanical parts and is used for various industrial fields such as automobiles, machinery, electric, electronic parts and semi-conductor.
It is excellent in strength and heat resistance, and is widely applied to precision machine parts.
Excellent electrical insulation, high impact strength, stability with temperature change and resistant to environmental changes are the main features of Engineering Plastics.
It is used for Electric and electronic fields, automobile exterior products, cameras and watches, and medical fields such as artificial organs.

Stainless Steel

Stainless Steel alloys with a minimum of 10.5% chromium content by mass and a maximum of 1.2% carbon by mass. Stainless steels are most notable for their corrosion resistance, which increases with increasing chromium content.
Additions of molybdenum increase corrosion resistance.
There are numerous grades of stainless steel with varying chromium and molybdenum contents to suit the environment the alloy must endure.
Stainless steel is ideal material for many applications where both the strength of steel and corrosion resistance is required.

Stainless steels are rolled into sheets, plates, bars, wire, and tubing to be used in: cookware, cutlery, surgical instruments, major appliances; construction material in large buildings,  industrial equipment (for example, In Mills, Chemical Plants, Power Plant, Water Treatment); and storage tanks and tankers for chemicals and food products.

Floor Finishing Materials (Laminate Floor)

Laminate Flooring is consisted of 3 layers.
(An upper laminated layer, a middle basis layer, a lower layer for blocking moisture.)
high-density fiberboard (HDF), which is formed by molding at high temperature and high pressure,

is used as a base material.
The surface is made of high-pressure laminate (HPL) or law-pressure laminate (LPL).
The surface gets laminating coating, 

and it is characterized by strong abrasion resistance, durability, stain resistance and easy maintenance.
Also, it is not only the construction period is short, 

but also the sound insulation and walk-ability are excellent.


H-Beam is composed of wide and thick flange and thin web, and it is widely used as structural steel because of excellent cross-sectional performance and easy assembly and joining of sections. Mainly used for high-rise buildings, factories, civil engineering, bridges, etc.

Like H-Beam, It consists of a flange and a web, but it has a narrow flange and a relatively thick web. Before the H-Beam was used, it was used as an assembly material, but it is used for some mines, bridges and vehicles since it is not used at present because of its low section efficiency.

Prefabricated High-strength H-beam system has no on-site welding procedure, but is done with joining each other with high-tension bolt, because it is prepared various length with proper positioning holes as ready-made H-Beam.
   H-beam are lower total costs of construction than traditional retaining wall system.

Advantage of using Prefabricated High-strength H-Beam

  • Reduce costs of construction about 30%
  • Accidental risk can be reduced about 50%
  • Shorten the construction period about 20%
  • Welding operation on shop can provide “ZERO” faulty product
  • Excellent corrosion resistance of anti-rust coating
  • Proper supply, large quantity demand can be acceptable
  • Design service of a retaining wall system