Rusty manhole covers how should I do? Gu Chang-year foundry to your Weapon: spray rust: is the use of oil-water separator treated by compressed air from the abrasive high-speed spray nozzle, the compressed air pressure is generally Zhang 4-0.6MPa, use with pressure mushroom-speed friction material and ductile iron manhole covers and shock on contact to remove scale and rust. This method does not need a fixed location, high efficiency, flexibility, large injection point, no dead corner of ink covers the company, in addition to the quality of the strike pound ink covers the specifications, while the ductile iron covers the surface roughness of the ball to get some ink covers manufacturer, Eli paint film adhesion, this method should be generally adopted. Gu Chang-year foundry cast iron manhole covers with you why are generally circular? The reason for using a circular cast iron covers can reverse thrust out from the negative point of the square cast iron covers. If a square ball ink wells, because it is significantly longer than the diagonal of the square on each side, so when the covers are rolled on, it is easy to fall into the wells diagonally wellhead, causing a safety hazard. If the wellhead or significantly less than the covers made of round, square manhole cover will not fall into the well. Wellhead wellhead use depends on the size, If you have to install an area much larger than the above wellhead square manhole cover, then the use of natural materials and practical value does not directly use the circular covers more efficient, but to make cast iron manhole cover price increases . Gu Chang-year foundry mainly produces all kinds of manhole covers. Welcome to buy! Ductile covers manufacturers _ Chang in foundry (certified) _ Liaoning ductile manhole cover provided by Gu Chang in foundry. Gu Chang-year foundry (www.sxcnzz.com) is Jinzhong, machining leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Chang-year leadership in the foundry staff warmly welcome all inquiries negotiations to create Chang foundry in a better future.