How to judge EPS block quality


Today we would talk something about how to judge EPS block quality.

(1)EPS block should have many pores on surface and you can discern beads figure 

on surface, if block surface is very smooth and have no pores, then block is very diffic-

ult to cool down. Inner steam is difficult to suck out, so that block need more much t-

ime for cooling and deform seriously;

(2)Press EPS block, block requirement is not crisp and not soft very much, if block 

is crisp, beads is easy to separate from block. then you have to increase heating press-

ure. If too soft, then decrease heating pressure;

(3)If outer surface is well-done, but when you cut block, and inside block is raw( b-

eads fall down easily). That mean heating one and heating two time is too short. You 

should close a little steam valve by hand.( actual time of preheating and heating one is 

near 15 second or so, experience for reference) Or the lower limit of heating three for 

get more pre-vacuum pressure;

(4)the higher block density is , the lower upper limit of heating one and heating two 

is ; the shorter the aging time of material is , the lower upper limit of heating one and h-

eating two is , heating pressure is very sensitive. Please adjust little each time;

(5)If cool down too much, the block will be shrink ( smaller), you should shorter cool-

ing time. Or Increase low limit of heating two.If the block have no  any deform, you can 

shorter cooling time until block have a little deform , then decide suitable cooling time .

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