We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Galvanised malleable iron threaded pipe cap, 3 1/2 inch

Anvil

Anvil 319900924 3 1/2 in Threaded Malleable Iron Cap

SKU CH-5W3D-GM3TR

A 3 1/2 inch threaded malleable iron pipe cap rated for 300 psi at 150 degrees F and 150 psi at 350 degrees F steam

  • Galvanized malleable iron resists corrosion for long service life
  • Threaded design allows quick installation on 3 1/2 in Schedule 40 and 80 pipe
  • Rated 300 psi at 150 °F for reliable high-pressure performance
  • Withstands 150 psi steam at 350 °F for demanding heating systems
  • Meets A197 specification ensuring consistent material quality

3 1/2 in Malleable Iron Threaded Cap

This Anvil cap terminates a 3 1/2 inch nominal pipe size run in malleable iron. It is rated for Schedule 40 and Schedule 80 pipe walls and uses standard NPT threads. The fitting meets ASTM A197 material requirements for general plumbing and industrial piping systems.

300 psi at 150 °F and 150 psi steam at 350 °F

Maximum operating pressure reaches 300 psi at 150 degrees Fahrenheit. Steam service is rated at 150 psi up to 350 degrees Fahrenheit. The temperature range spans minus 20 to 350 degrees Fahrenheit. No pre-applied thread sealant is included so installers must apply their own compound or tape.

Solid plug construction with galvanized finish

The cap features solid plug construction without a drive recess, requiring a pipe wrench on the hex body for installation. Galvanized coating provides corrosion resistance in water, air and steam lines. Threads are cut to accept standard NPT connections on Schedule 40 or Schedule 80 pipe.

Highlights

  • Galvanized malleable iron resists corrosion for long service life
  • Threaded design allows quick installation on 3 1/2 in Schedule 40 and 80 pipe
  • Rated 300 psi at 150 °F for reliable high-pressure performance
  • Withstands 150 psi steam at 350 °F for demanding heating systems
  • Meets A197 specification ensuring consistent material quality

Specifications

BrandANVIL

Questions about this item

How do I install the 3 1/2 in threaded malleable iron cap and what step is commonly missed?

Thread the cap onto Schedule 40 or Schedule 80 pipe by hand, then tighten with a pipe wrench. The step often missed is applying PTFE tape or pipe dope to the male threads before assembly to ensure a leak-free seal at 300 psi.

What maintenance or replacement will this galvanized A197 cap need over time?

The galvanized coating resists corrosion, but in harsh water or outdoor exposure it can wear down. Inspect threads and body annually for white rust or pitting; replace the cap if the iron substrate is exposed or threads no longer seal at 150 psi steam rating.

Which pressure or temperature limit will be reached first during sustained high-temperature service?

At 350 °F the maximum steam pressure is 150 psi, while at 150 °F the rating is 300 psi. Sustained steam service will hit the 150 psi limit first, so design the system to stay below that threshold for continuous operation.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.