Dzulkifli said out of the five schemes, the Retail Prosper and Wholesale Prosper were the most popular schemes among entrepreneurs, hence PUNB
has made higher allocations for the two schemes totaling to RM160 million, or RM80 million each.
For both PUCB and PUNB, the Part land Part II of the binder were added at a rate of 1% of sand (and split 55/45% between Part I and Part II, respectively).
To provide for total capture of the VOCs, the PUNB production scenarios and all storage areas were designed following the criteria established for permanent total enclosures.
Following a review of the cost-effectiveness study report, Ohio EPA agreed that the cost effectiveness numbers of VOC controls on core- and moldmaking operations using PUCB and PUNB binders greatly exceeded the acceptable range.
35 tons/hr for 8 hr/day VOC emission rate of 40 lb/day Core storage for 12 hr after production Scenario #2 PUNB core production and storage Production rate of 4.
Although the recommended PUNB binder ratio varies between a 55:45 and 60:40, in actual practice, ratios favoring excess Part II often result from worn or defective binder pumps, air in binder lines, changes in binder viscosity from temperature and inefficient mixing.
Since the chemistry and gaseous thermal decomposition products for PUNB binders are more complex than interactions with green sand molds, the performance of ductile iron with these binders may differ considerably.
50% 35:65 severe Test conditions: PUNB binder with washed and dried silica sand; Iron Chemistry, 4.
Recognizing these 12 facts and practicing the 15 tips that follow can help you make the PUNB process work - as intended - for your foundry.
Success with the PUNB process boils down to two words - process control.
The odor associated with PUNB, and especially eye irritation, is usually a result of formaldehyde emissions at very low concentrations.
Meanwhile, they discovered lustrous carbon formation in PUNB
cores occurs in a reducing atmosphere at temperatures as low as 1000F (538C) and between 15 minutes and three hours.