The main process of the ceiling made of PU board as the skeleton material is dry method and wet method.

1. Dry process: non-woven fabric at the bottom → unwinding → glass fiber scatter → dusting → PU board → glass fiber → dusting → preheating → heating → composite → cooling → closing plate → substrate + surface decoration Layer → Cold Molding → Cutting → Pressing Riveting Fixture Frame → Mounting Accessories → Ceiling Assembly


2. Wet process: 1. Non-woven fabric → unwinding → glass fiber spreading → glue spraying → PU board → glass fiber spreading → glue spraying → preheating → closing plate → substrate → hot moulding → top shell + surface Finishing layer → hot stamping → cutting → pressing riveting lamp fixing frame → installation accessories → ceiling assembly

material type

1. In the face decoration: knitted fabric, non-woven fabric, PVC fabric

2. Base material: PU rigid foam board, hemp fiber board, corrugated cardboard, FS board, PS board, PP board, waste textile felt, etc.

Ceiling processing technology

1. Compound process


The task of the compounding process is to transfer various materials such as the backing layer, the adhesive layer, the glass fiber layer, and the PU board layer to the heating area and the cooling area, and then make them into a sandwich board or a substrate after heating and compounding and cooling and setting. (The adhesive layer mentioned here is usually a thermoplastic adhesive, which bonds multiple layers of material together when heated to a molten state)


2. Molding process


After the base material produced in the compounding process is heated, the base material is sufficiently softened, and the base material and the facing layer are simultaneously molded by a mold, that is, the initial shape of the ceiling.


3. Cutting process

The work of this process is to use a three-dimensional high-pressure water cutting equipment-robot to program to cut the roof burrs and holes.


Riveting process

Some ceilings (especially European models) have metal ceiling light fixing frames on the assembly. The job of this process is to rivet the light fixing frame to the ceiling.


Summary of ceiling processing technology

1.The dry ceiling material structure is generally fabric / adhesive powder / glass fiber / PU rigid foam board / adhesive powder / glass fiber / non-woven fabric.

2. The structure of wet ceiling material is generally fabric / adhesive / glass fiber / PU rigid foam board / adhesive / glass fiber / non-woven fabric.

3. The mechanical properties of the dry and wet ceilings are basically close to each other. The dry process has the advantages of high efficiency and environmental protection. The dry roof is slightly full on the senses. The wet process requires two sets of molds. , High efficiency. Wet process usually uses solvent-based adhesives. The production process emits a large amount of organic solvents. The environmental protection is not as good as the dry method, but the water-soluble environmentally-friendly adhesives for ceiling production that are currently being studied internationally are about to enter industrial production.

Superiority

Japan, Korea and other countries used corrugated cardboard and PS board (polystyrene) to make ceilings in the early days. Due to their shortcomings such as easy deformation, moisture absorption, sound absorption, poor heat insulation performance, and difficulty in processing and tearing, FS boards and PU rigid foam board; currently corrugated cardboard and PS board are mainly used in low-end cars, such as Geely Uliou, Geely and Japan. European and American countries are widely used in the production of car roofs because of its excellent stability, safety, sound absorption and moisture resistance, such as Audi, Bora, Picasso, Xana, Odyssey, etc.

The experimenter used PU panels, PS panels, and hemp made of hemp fiber to conduct climate simulation and exposure tests. As a result, the ceilings produced from PS board and hemp fiber were severely deformed, and the fabric was foamed. The roof of the PU board is slightly deformed.

The roof of trucks produced in China is mainly made of hemp fiberboard because of higher rigidity requirements and lower performance requirements. Now some car roofs are made of waste felt, such as Beijing Hyundai.