ASTM D2688 Test Coupon
Metal test coupons used in ASTM D2688 (Corrosivity of Water in the Absence of Heat Transfer - Weight Loss Method). The metal test coupons are mounted on pipe plugs and exposed to water flowing in municipal, building, and industrial water systems. The coupons come in two sizes: 1/2" x 3" x 0.062" (sheet metals) with a 5mm hole centered 3mm from one end; and 1/2" x 4" x 1/8" (cast metals) with a 7mm hole centered 8mm from one end.
ASTM D2688 test coupons are available in a range of different metals, including steel, cast iron, copper, and zinc. The test coupon should be the same or a similar metal to the water pipe system.