Ammonia pump cylinder modifying method

The invention discloses an ammonia pump cylinder modifying method. The ammonia pump cylinder modifying method includes surfacing corrosion-resistant metal materials on a corroded part contacting with medium on the surface of an ammonia pump cylinder, subjecting the surface of the ammonia pump cylinder to surface treatment after surfacing, and surfacing the ammonia pump cylinder via welding rods. The ammonia pump cylinder modifying method is applicable to the technical field of urea production, and can be used for cylinder optimization on the basis of an existing cylinder, overall service life of the ammonia pump cylinder can be prolonged, and corrosion resistance inside the pump cylinder is effectively improved. The ammonia pump cylinder modifying method is easy to popularize and capable of solving the problem that the cylinder cannot be completely replaced due to shortage of funds, maximizing resource utilization and effectively saving equipment investment of enterprises.