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Black rubber mechanical test plug with ABS plate, 3-1/2 inch size

Safe-T-Seal

Safe-T-Seal MTP352 Mechanical Test Plug Rubber 3-1/2 in

SKU CH-FNTF-J1H6E

A rubber mechanical test plug for 3-1/2 inch pipe, sealing 0.38 to 3.5 inch inside diameters with 22 psig air or 50 ft water back-pressure rating

  • Seals pipes up to 3.5 in inside diameter with rubber expansion
  • Withstands 50 ft of water head for reliable pressure testing
  • Holds 22 psig air pressure for pneumatic leak checks
  • ABS plate resists corrosion during repeated use
  • Fits minimum 0.38 in pipe ID for versatile application

Mechanical test plug for 3-1/2 in pipes

The Safe-T-Seal MTP352 is a rubber mechanical test plug sized for 3-1/2 inch pipe inside diameter. It seals inside the pipe to block flow during pressure testing or temporary isolation. The plug fits a minimum inside diameter of .38 in and a maximum of 3.5 in.

Holds 22 psig air and 50 ft water head

Under sustained load the plug resists up to 22 psig of air back pressure and 50 ft of head water pressure. The ABS plate and rubber seal maintain the seal without a bypass connection or water fill port. It is rated for these pressures during extended test periods.

Hand-tightened with padlock option

Installation is by hand tightening the mechanical expansion mechanism inside the pipe; no tools are required. The handle accepts a padlock shackle to prevent accidental release. California Proposition 65 warning applies because the product contains a chemical known to cause reproductive harm.

Highlights

  • Seals pipes up to 3.5 in inside diameter with rubber expansion
  • Withstands 50 ft of water head for reliable pressure testing
  • Holds 22 psig air pressure for pneumatic leak checks
  • ABS plate resists corrosion during repeated use
  • Fits minimum 0.38 in pipe ID for versatile application

Specifications

BrandSAFE-T-SEAL

Questions about this item

How much back-pressure can the 3-1/2" mechanical plug hold when I pressure-test with air all day?

The plug is rated for 22 psig maximum back pressure with air, so it will seal continuously at that level without leaking.

What pipe inside diameter range does the MTP352 cover so I know if my existing 3-1/2" line will accept it?

It fits pipes with an inside diameter from .38 in up to 3.5 in, matching standard 3-1/2" pipe size.

Will the ABS plate and rubber seal hold up against the older cast-iron drains I am keeping in place?

The ABS plate and rubber seal are designed for inside-pipe sealing and withstand 50 ft of head water pressure, compatible with existing cast-iron lines.

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