Abstract

A process for preparing a spheroidal graphite cast iron screw pile, comprising the steps of pre-pile-casting preparation, pile casting, heat treatment, and finishing. Further disclosed is a spheroidal graphite cast iron screw pile prepared using the spheroidal graphite cast iron pile preparation process, comprising a guide pipe, the lower end of the guide pipe having a slope apex, and at least two spirally rising rotors being arranged along the axis of the guide pipe, the guide pipe being a straight guide pipe, an inverted cone guide pipe, or a profile guide pipe. The spheroidal graphite cast iron screw pile has tensile strength of not less than 420-500 MPa and elongation of not less than 7-10% and features strong corrosion resistance and long service life.

IPC Classes  ?

• C21C 1/10 - Making spheroidal graphite cast-iron
• C22C 33/08 - Making cast-iron alloys
• E02D 5/56 - Screw piles

Abstract

The invention discloses a high strength nodular cast iron pole and a preparation technology thereof. The preparation technology is characterized by comprising the following steps: (1) preparation before pole casting, to be specific, preparation of raw materials, smelting of iron, adding of alloying elements and nodulizing; (2) a pole casting procedure, to be specific, casting and inoculation treatment; and (3) heat treatment. The invention also provides the high strength nodular cast iron pole prepared by adopting the preparation technology, comprising multiple tower poles which are sequentially connected in an inserted manner, wherein each tower pole is a cone-frustum hollow column which has the conicity of 1000:11-26; the top end of the high strength nodular cast iron pole is equipped with a tower cap. The high strength nodular cast iron pole has the advantages of high bearing capacity, thin wall thickness, light weight, low manufacturing cost and the like.

IPC Classes  ?

• C22C 37/10 - Cast-iron alloys containing aluminium or silicon
• C22C 37/06 - Cast-iron alloys containing chromium
• C22C 33/08 - Making cast-iron alloys
• C22C 37/04 - Cast-iron alloys containing spheroidal graphite
• C21D 5/00 - Heat treatment of cast-iron
• C21D 9/00 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articlesFurnaces therefor