Rotomolding Company Achieves Consistent PE Powder Quality for Large Water Tanks

Rajesh Patel, Managing Director — India

Before ZPM-600, our powder quality was inconsistent — some batches had too many large particles causing pinholes in our tanks. The disc mill with precision gap control gave us the consistent particle size distribution we needed. Our defect rate dropped from 4.5% to less than 1%.

— Rajesh Patel, Managing Director

Project Background

A rotational molding company near Ahmedabad, India, producing polyethylene water storage tanks ranging from 500 to 5,000 liters was purchasing PE rotomolding powder from external suppliers at a premium. The company consumed approximately 200 tons of PE powder annually. Inconsistent powder quality from different suppliers caused variable wall thickness and occasional pinhole defects, directly impacting their warranty claims and customer satisfaction.

Our Solution

Zhiyi Machine configured a ZPM-600 disc-type PE pulverizer system:

  • ZPM-600 disc mill with 55 kW motor and tungsten-carbide coated grinding discs
  • Liquid nitrogen (LN2) cryogenic cooling option for LLDPE grades
  • Precision disc gap adjustment (0.3-0.8mm) for exact PSD control
  • 16-bag pulse filter dust collector
  • Vibratory feeder with VFD-controlled feed rate

We conducted material testing with their specific PE resin grade to establish the optimal disc gap and classifier screen configuration targeting a 30-60 mesh particle size distribution.

Results & Impact

  • Powder quality: Consistent 30-60 mesh PSD with less than 5% oversized and under 15% fines
  • Defect rate reduction: From 4.5% to 0.8% — saving approximately $45,000/year in warranty costs
  • Material cost savings: $65,000/year by processing PE pellets into powder in-house versus purchasing pre-ground powder
  • Production flexibility: Ability to switch between PE and LLDPE grades with simple parameter adjustments
  • ROI: Full payback in 14 months

Want Similar Results for Your Operation?

Tell us about your material and production goals — our engineers will recommend the right configuration for your needs.

Start Your Project →