Hercules
Hercules 15433 Pro Dope Pipe Thread Sealant 6 lb Pail Gray
Non-hardening gray paste seals pipe threads on aluminum, brass, copper, steel and stainless up to 350 °F and 250 psi liquid pressure
- Non-hardening formula allows future disassembly
- Withstands 350 °F for high-heat steam lines
- Seals up to 250 psi liquid pressure
- Compatible with stainless steel and copper pipes
- Six-pound pail covers many professional jobs
Pro Dope pipe thread sealant
Hercules 15433 Pro Dope is a non-hardening paste sealant supplied in a six-pound pail. It is formulated for general-purpose thread sealing on piping systems that carry air, natural gas, steam or water. The product suits plumbers, HVAC technicians and maintenance crews who need a reliable joint compound for mixed-metal installations.
Temperature range and pressure limits
The sealant remains effective from zero to three hundred fifty degrees Fahrenheit. It withstands gas pressures up to two hundred psi and liquid pressures up to two hundred fifty psi. Because the compound does not harden, joints stay flexible under thermal cycling and vibration without cracking or weeping.
Material compatibility and container format
The gray paste is approved for aluminum, black iron, brass, copper, galvanized steel and stainless steel threads. The six-pound pail provides enough volume for multiple large-diameter jobs while keeping the paste protected from contamination between uses.
Highlights
- Non-hardening formula allows future disassembly
- Withstands 350 °F for high-heat steam lines
- Seals up to 250 psi liquid pressure
- Compatible with stainless steel and copper pipes
- Six-pound pail covers many professional jobs
Specifications
| Brand | HERCULES |
|---|
Questions about this item
How do I apply the Pro Dope paste to pipe threads without over-filling the joint?
Brush a thin, even coat onto the male threads only, covering the first few threads completely; excess paste can be pushed into the flow path and restrict pressure-rated systems.
Will the non-hardening sealant need to be reapplied after thermal cycling between 0 °F and 350 °F?
The paste remains pliable across the full temperature range, so it does not harden or crack; reapplication is only required if the joint is disassembled.
At what pressure will the sealant reach its limit first on a steam line?
The rating for gases and steam is 200 psi, which is lower than the 250 psi liquid rating, so sustained steam pressure above 200 psi will exceed the sealant’s limit first.
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