... C-- socket-weldingBearing bar centers15-30, 40, 60, 80, 90 mm etc. with 30, 40 mm recommended.Cross bar ... centersany greater than 30mm is ok. with 50, 100mm recommended. ... grating is the most commonly used in projects with American, Australian, Japan standards are available. This ... pitch12.5, 15, 20, 23.85, 25, 30, 30.16, 30.3, 34.3, 35, 40,41,60mm. US ...