High density sponge refers to the sponge with a net weight of 45KG per cubic meter.
Generally speaking, high-density sponge has good air permeability and other characteristics, so it is related to various industries, including automotive industry, shock absorption, flame retardant, antistatic, heat insulation, sound-absorbing polyurethane sponge, because of its thermal insulation, battery industry, cosmetics industry.
1 .classification.
The difference between sponges in manufacturing lies in the relative density.
The relative density of sponge is KG/M3.
That is, the net weight per cubic meter of sponge.
According to its structure, common sponges are divided into three types: high density sponge, medium density sponge and low density sponge.
There are many high-density sponge holes and they are very round.
Often used as sound-absorbing cotton, sofa cushions, hard bags and other raw materials.
According to the national Chinese customs units, relative density ≥ 45 is high density, between 45-18 is medium density, and relative density
2 .definition of relative density.
In physics, the volume mass of a chemical enterprise is called the density of the substance.
Mark ρ (pronounced rudu).
The most important enterprise is KG/m3, and g / cm3 is also common.
The relation of math class is ρ = mcompV.
In the unit system, the main body of mass is KG, and the main body of volume is cubic, so the mass of 1 cubic meter of chemical substance is taken as the density of the substance.
For asymmetric chemicals, it is called "average relative density".
3 .Index value of relative density of sponge.
Relative density is a key index value of chemical substances.
The relative density of the sponge is high, which means that the gap inside is smaller and the quality is better.
For example, 40 relative density represents a cubic sponge net weight of 40kg per cubic meter 50 relative density represents 50KG per cubic meter.
4 . strength of high density sponge.
Generally speaking, high-density sponges have high strength, but some dirty high-density sponges will add soft modifiers to make the sponges soft and light.
Used for sound absorbing cotton, sofa cushion, hard.
Packaging raw materials.
Medium and low density sponges are used as general maintenance materials.
Sponges with the same relative density have different degrees of softness and hardness.
5. use high density sponge.
It has the function of digesting and absorbing external forces, and has the characteristics of delicate touch, softness and comfort.
In small cars, furniture, health, small toys and other manufacturing industries, we can consider the needs of various markets.
(6) the upper and lower density of bulk sponge will be different in foam production.
Mainly due to the influence of gravity, there is a density gradient problem at the top and bottom of the sponge.
The difference between the upper and lower density of the powderless sponge is not obvious, and there is a certain difference allowed by the standard.
Many manufacturers in order to reduce costs, mainly due to the role of gravity, often add a certain amount of stone powder to the foam, which will make a great difference in density between the upper and lower.
There is a density gradient problem on the upper and lower sides of the sponge.
The difference between the upper and lower density of the powderless sponge is not obvious, and the standard allows for some differences.
1. Precipitation of raw materials.
It would be better if it was pure material.
If it is powdered, there will be a big difference between the upper and lower sides.
2. When foaming, the raw material is only a layer of water, and the chemical reaction is carried out from the bottom to the top and rises slowly.
Therefore, in the process of storage, first of all, we should pay attention to keep away from the open fire, and secondly, we should prevent the fire and irreparable loss caused by charge accumulation and electrostatic discharge.
Fire precautions on the inner drawings of pearl cotton packaging should be popularized by warehouse staff and regular investigations should be conducted during normal working period.
Strict requirements to avoid irreparable losses.
