Hercules 15-420 Pro Dope Pipe Joint Compound – 1/2 Pint

The Hercules 15-420 Pro Dope is an oil-based, non-hardening thread sealant formulated for use in mechanical and plumbing applications requiring a reliable, leak-tight joint. It is designed for professional-grade sealing of metallic and non-metallic threaded pipe connections under a wide range of service conditions. The compound’s non-drip, non-separating formulation provides extended working time, corrosion resistance, and ease of disassembly after service exposure.

Details

• Manufacturer: Hercules
• Model Number: 15-420
• Product Name: Pro Dope Pipe Joint Compound
• Container Type: Metal can
• Container Size: 1/2 Pint (8 fl oz)
• Net Weight: 0.92 lb (417 g)
• Formulation Base: Oil-based compound
• Physical Form: Liquid paste
• Color: Gray
• Odor: Fish oil characteristic
• Composition:
  • Calcium Carbonate
  • Petroleum-based Lubricating Oil
  • Kaolin
  • Menhaden Oil
  • Quartz
• Temperature Range: 0°F to 350°F (-18°C to 177°C)
• Application Temperature Minimum: -15°F (-26°C)
• Flash Point: 212°F (100°C)
• Viscosity: 30,000 cP
• VOC Content: 11 g/L
• Pressure Ratings:
  • 250 PSI for liquids
  • 200 PSI for air/steam
• Applicable Materials: Aluminum, Black Iron, Galvanized Steel, Brass, Copper, Stainless Steel, Glass, Monel
• Curing Characteristics: Non-hardening, non-separating formulation
• Corrosion Resistance: Provides rust and corrosion inhibition through a protective film on threads
• Toxicity: Non-toxic, lead-free formulation
• Application Method: Apply with natural bristle brush supplied with can

Technical Application

Hercules Pro Dope is designed for sealing threaded metal pipe joints in mechanical, plumbing, and process systems. It is suitable for installations handling natural gas, compressed air, steam, hydronic heating fluids, ammonia, brine, diluted acids, and fire protection systems. The compound maintains pliability for extended service life, ensuring that joints can be disassembled without galling or thread damage. Its non-drip characteristics make it suitable for overhead or confined applications. The formulation remains stable under cyclic pressure and thermal variations, delivering consistent sealing integrity under varying mechanical loads.

Specifications

• Type: Oil-based, non-hardening thread sealant
• Base Material: Petroleum oil with inert fillers and calcium carbonate
• Temperature Range: 0°F to 350°F service; applicable to -15°F
• Pressure Limits: 250 PSI (liquids), 200 PSI (air/steam)
• Viscosity: 30,000 centipoise
• VOC Level: 11 g/L
• Flash Point: 212°F
• Form: Non-drip, gray liquid paste
• Application Equipment: Natural bristle brush
• Corrosion Protection: Inhibits oxidation and rust on metallic threads
• Service Media Compatibility: Air, water, steam, gases, oils, and process chemicals
• Compliance: Lead-free, non-toxic formulation suitable for industrial use

Summary

The Hercules 15-420 Pro Dope Pipe Joint Compound provides a durable, non-hardening thread sealant suitable for professional-grade installations across gas, hydronic, and process piping systems. Its oil-based formulation ensures leak-tight performance, corrosion protection, and ease of disassembly while maintaining stability across a wide temperature and pressure range. Engineered for field reliability, Pro Dope delivers consistent sealing performance on multiple metallic substrates used in industrial and commercial applications.