Grade A boiler manufacturer low cost of maintenance boiler membrane water wall is main radiation heat surface, arranged inside the boiler chamber and proceeds the heat exchange directly with the high temperature flame. The convection tubes are the convection heat surface of the boiler, arranged between the boiler chamber outlet and the end heat surface and proceed the heat exchange directly with the high temperature fume. Water recycling system water wall panel and convection tubes are the main heat surface of the boiler, the tubes diameter for both Generally used Ï?51~60mm boiler steel tubes, also as the request.