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        # Monsoon Alert: How Humidity Destroys Your PVC Production

        

**Topic:** Production

        

Every July, your rejection rate triples. Bubbles appear in your sheet. Your blowing agent goes haywire. Your resin clumps in the hopper. Welcome to monsoon manufacturing in Delhi.

        
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## Problem

Delhi's monsoon brings relative humidity of 80-95%. This moisture infiltrates every raw material in your warehouse: PVC resin absorbs surface moisture causing clumping and poor flow; Calcium Carbonate fillers become hygroscopic; blowing agents pre-decompose partially; and even CPW can develop haze if water ingress occurs in storage tanks. The cumulative effect is a catastrophic rise in reject rates, sometimes exceeding 15-20% of output.

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## Likely cause

This issue often stems from inconsistent compounding temperatures, inferior raw material purity, or unbalanced stabilizer ratios within the formulation matrix.

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## Corrective direction

NBT's **Monsoon Production Protocol**  -  developed over 35 years of supplying Delhi-NCR factories  -  covers three pillars: **Storage**  -  all NBT raw materials are dispatched in moisture-sealed packaging with silica gel desiccants; **Pre-Processing**  -  we recommend inline drying of resin at 80°C for 2 hours and pre-conditioning fillers in a heated mixer; **Formulation Adjustment**  -  slightly increase your stabilizer loading by 0.5-1.0 PHR during monsoon months to compensate for any trace moisture. Our technical team provides free monsoon audits for regular clients.

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          ## Frequently Asked Questions

          
### Should I change my blowing agent PHR during monsoon?

Not necessarily the PHR, but ensure your blowing agent is stored in sealed containers. Moisture causes premature decomposition, which reduces effective gas yield.

### How do I test moisture content in resin?

A simple loss-on-drying test at 105°C for 2 hours will give you the moisture percentage. It should be below 0.3% for trouble-free processing.

        
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By NBT Technical Desk · Updated 2026-06-07

        

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