Selecting a potting resin is not just a question of brand or hardness. The wrong system can lead to incomplete cure, mechanical cracking, service difficulties, or application failure. This guide covers the five most important criteria to evaluate when choosing a potting resin.
Criterion 1: Service Access — Will the Connection Need to Be Reopened?
This is the first question to ask. If the cured system will ever need to be re-entered for probe measurement, inspection, or repair — rigid resin is the wrong choice.
- Permanent application: Rigid polyurethane or epoxy
- Serviceable application: NCflex elastic re-enterable system or NCgel silicone gel
Criterion 2: Viscosity — How Should the Resin Flow?
- Low viscosity: Small voids, narrow channels, and complex geometries
- High viscosity: Vertical surfaces, open molds, and controlled-fill applications
Criterion 3: Hardness and Modulus — How Rigid Should the Cured System Be?
- High hardness (Shore D): Strong resistance to mechanical impact and pressure
- Low hardness / elastic (Shore A): Vibration tolerance and thermal expansion compliance
Criterion 4: Operating Temperature Range
Not all polyurethane systems perform equally across temperature ranges. For outdoor installations, motor or transformer proximity, and cold climates, temperature range is critical. Polybutadiene-based systems such as NCflex maintain elastic behaviour at low temperatures due to their low glass transition temperature (Tg).
Criterion 5: Application Method — Factory or Field?
- Factory / laboratory: Precision scales, mixers, and dispensing equipment available
- Field application: NCpack dual-component pouch format — no containers, scales, or mixing tools needed
Selection Summary Table
| Criterion | Rigid System | Elastic (NCflex) | Gel (NCgel) |
|---|---|---|---|
| Service access | ❌ Difficult | ✅ Hand-removable | ✅ Hand-removable |
| Low-temp performance | Moderate | ✅ Good | ✅ Good |
| Mechanical strength | High | Moderate | Low |
| Field application | Easy with NCpack | Easy with NCpack | Easy with NCpack |