Foam caulkIn the production process How to avoid bubbles

PolyurethaneFoam caulkThe generation of bubbles is related to: foaming, machinery, and raw material formula. Today we will talk about foaming.

1. Foam caulkFoaming:

Foam caulkWhen the temperature is not high enough and does not reach the temperature required for product production, it is possible to open the mold at the normal production speed. To generate bubbles, there are actually three different materials: steel mold, aluminum mold, resin mold, copper mold, and fiberglass foaming that have faded out of sight in recent years.

1. Some production units Warm in electric oven.

2. Some use water for heating.

3. Some even use gas for heating. Relatively speaking:

A .The cost of electric heating is higher, and it is used for continuous production and large-scale production, and requires higher operating proficiency.

B. Water heating , simple, convenient and easy to control.

C. Gas heating It is not advisable. Fireworks are prohibited in the original place of production. It is unsafe, dangerous and difficult to control.

Steel molds and aluminum molds need to be prepared for heating during production. Some have grooves on the surface, and then bury aluminum tubes to transfer heat through the aluminum tubes. Some directly drill holes in the foam. I think they can be drilled directly. The hole is the best, convenient and the heating is the most direct. The low temperature of the mold will produce bubbles, and the curing time is not enough. Foam caulk If the temperature is too high, the product will be more inflated and prone to cracking when opening the mold. For the production of different foaming cables, for example, the steel mold requires 45 degrees Celsius, or the resin mold requires only 40 degrees Celsius. The water inflow of the ball valve of the water pipe can be appropriately adjusted to achieve the temperature control effect. In general, foaming and heating contribute to relatively little self-skinning bubbles.

2. Foam caulkExhaust:

Some foaming requires exhaust to reduce the formation of bubbles.

A .The foam surface directly opens holes1.0~1.5 mm perforation is better, but it is too large. The scar is too big after the nail is cut.

B. Foam caulking AgentPeripheral exhaust is called grooving. You can use a blade, saw blade, or grinding No matter which method is used, it should be noted that when grooving, the closer to the parting line, the shallower it should be. When you are far away from the parting line, you can make it a little deeper, from shallower to deeper. If the parting line is too deep, it will directly affect the appearance of the product and the scars after trimming.�Too large. The position of the exhaust holes and exhaust grooves is usually to place the foam in the normal positionFoam caulkangle, determine the exhaust according to the product The best position for holes and exhaust slots is to open as few exhaust holes and exhaust slots as possible. When products with high requirements cannot have vent holes and vent grooves, put them in place after shaking the moldFoam caulkView, the mold Buckle it lightly and wait until it has foamed outfoam caulkWhen you are on the edge, you can quickly buckle the mold to achieve the effect.

Three, Foam caulkBubbles may also occur when the foaming position is inappropriate:

Some foam and lay flat, some Some foaming requires angles and 360-degree rolling of the mold. Personally, I think the product requires a flat surface. If the front is not strict, you can rock the mold back and forth and put it in the best position. If the product’s appearance matches the The back side also has strict requirements. At this time, we must consider that 360-degree shaking of the mold means shaking the material to the back of the product to reduce the generation of air bubbles.