E7028 is a high deposition (rate) SMAW electode that meets the requirements of a low hydrogen electrode. It is used for flat grooves and flat and horizontal fillet welds. As is the case with all low hydrogen electrodes with limestone based fluxes, it has to be stored in an electrode oven to prevent the acummulation of moisture in the flux covering and the exposure time must be limited because of the hygroscopic properties of the covering. The slag is easily removed if the proper welding parameters are employed. Difficult slag removal is a good indication the welding parameters are incorrectly set.
Best regards - Al