A metal ring placed around the drainpipe to secure the roof drain to a surface, such as a roof deck or parapet wall. It is also called a clamp collar, clamp ring, drain ring or flashing ring.
Commercial cast-iron roof drains are often subjected to heavy weathering and regular wear and tear. As a result, their parts—including domes, rings, sump pans, and clamps—sometimes break, crack or rust over time, and need to be replaced.
Clamp Ring Sizes of Roof Drain:
There are 5 ways to take the measurement of the cast iron drain ring sizes:
(1) 4-Bolt Ring: Measure the bolt slots directly across the ring at 180 degrees.
(2) 3- or 5-Bolt Ring: Measure the distance between neighboring bolt slots, as they go around the inside of the drain ring.
(3) Inner Diameter (I.D.): Measure the distance between the ring's inside edge of the gravel stop, directly across at 180 degrees.
(4) Outer Diameter (O.D.): Measure the distance between the ring's outside edges at 180 degrees. Include any lip or flange that extends beyond the gravel stop.
(5) Lug Style: Lug style drains are measured the same as bolt-style drains, except the measurement is taken from the center of the pad's dimple.
Cast iron clamp drain ring |