logo white
Home » Paper Pulp Tray Manufacturing FAQ

Paper Pulp Tray Manufacturing FAQs


AGICO summarizes some frequently asked questions in the production process of paper pulp trays and gives detailed answers.

agico logo blue

Do you have any other questions or just want to consult our pulp molding machines? Don’t hesitate to contact us!

First, the paper pulp concentration is changing all the time. When a small part of paper pulp is attached to the mold during the production process, the concentration of the remaining pulp is changed, and the change is generally controlled between 2.56% and 3.6%.

Second, the vacuum is also changing constantly. In the pulp molding system, the negative pressure value produced by the negative pressure tank (a part of the air compressor) is a variable during the production process. For the above two reasons, the weight of paper trays with the same pulp suction time changes between ± 10%.

The dyeing of paper pulp trays is mostly realized by adding water-soluble dyes to the original paper pulp in the pulp proportioning process. However, the uneven paper pulp concentration affects the concentration of the dye. And most dyes are sensitive to temperature: 

1. In the drying process, the color of paper trays will be affected by the high temperature. 

2. During working, the temperature of the hot press machine will reach 150-250 ℃ so the shaping of the paper pulp tray will also cause color changes.

The paper pulp trays are semi-wet after demolding. After the drying process, they will be deformed to some extent. We usually use a hot press machine with high temperature (150 ° ~ 250 °) and high pressure (3T ~ 50t) to further refine the appearance of paper trays. AGICO fully automatic hot press machine features energy-saving, low noise, and high precision, which is a good choice for you.

When the wet paper tray is just formed on the mold, the pulp fibers naturally stack together layer by layer. However, the liquid paper pulp has fluidity and will flow out from mold grooves, resulting in an uneven thickness of the paper tray after a high-temperature drying. When the fully-dried paper pulp tray is squeezed by a strong external force, the outermost fiber is easy to break and form small cracks. This phenomenon will not weaken the strength of the paper tray, so it will not affect the use.

1. If the customer can send a sample, it is the best way. We will look for molds that are similar in size and shape to the sample or customize the mold directly.

2. If there is no sample, please make sure that you can provide the following data:

egg tray size

Outer size of paper pulp tray (length and width)

egg tray cavity depth

Depth of cavity

egg tray cavity size

Cavity length and cavity diagonal length

We will try our best to find similar molds for you or make a drawing according to the data you provide. After your confirmation, we will customize the mold for you.

No, the raw material applied to manufacture paper pulp tray should contain long fibers. Agricultural wastes, such as straw and bagasse need special treatment (made into plant fiber pulp) before they are used for production. Agricultural residues cannot be used as raw materials directly.

AGICO paper tray molds are commonly made of plastic, aluminum, or half plastic and half aluminum. The service life of plastic molds can reach more than 2 years and AGICO offers a one-year warranty. The service life of aluminum molds can reach more than 3 years and AGICO offers a two-year warranty.

Yes, we will dispatch engineers to assist customers in the installation of equipment. Besides, we also offer free remote installation services which include professional guidance video, installation manual, and online guidance of technicians.

Scroll to Top

Reach Us For Help

We receive enquiries in English, Japnese, Español (Spanish), Русский язык (Russian), Français (French) and العربية (Arabic). Please feel free to contact us!

WhatsApp Message