Worm shaft is also known as worm screw or vortex rod. A worm shaft is a gear in the form of a screw.
The friction between worm shaft and worm gear under work causes a lot of heat. High friction and high heat usually wear out the surface of tooth of worm shaft and worm gear. That is why worm shaft should use the materials which have wear resistance and high rigidity.
The materials of worm shaft we recommend are as below.
- Related List
Equivalent Grades: GB 40CrNiMoA, 45CrNiMoVA, JIS SNCM439, and ASTM 4340, 9840. SNCM439 is a kind of refining steel and has the properties of high hardness and toughness. It is often used for the manufacture of screws, gears, shafts, nuts, pistons, the automobile parts required high toughness and so on.
Equivalent Grades: JIS SNCM420 and ASTM 4320. SNCM420 is mainly used for railway bearings, drive shafts, gears, screws, cutting tools and other products which need impact resistance and wear resistance. SNCM420 is a kind of alloy carburizing steel as SNCM220. The mechanical properties between SNCM420 and SNCM220 are almost the same. The surface of SNCM420 is high hardness and has good performance in abrasion resistance and contact fatigue strength. Its core which has high toughness can withstand high impaction. There are two differences between SNCM420 and SNCM220 which are the standard and the amount of Ni content. The Ni content of SNCM420 is more than the one of SNCM220.
Equivalent Grades: GB 20CrNiMo, JIS SNCM220, ASTM 8615, 8617, 8620, 8622, DIN 20MoCr4. SNCM220 is mainly used for automobile bearings, drive shafts, gears, screws, cutting tools and other products which need impact resistance and wear resistant. SNCM220 is a common type of alloy carburizing steel or bearing steel with the surface of high hardness, abrasion resistance and contact fatigue strength. Its core which has high toughness can withstand high impaction.
SCM440 is medium carbon chromium molybdenum alloy steel, which is an alloy steel containing chromium and molybdenum. It has the advantages of stable composition, low harmful elements, high steel purity, small decarburization layer and few surface defects. It is easy to be spheroidized and has low cold cracking rate. It is usually hardened and tempered. The ultimate tensile strength is 850-1000 Mpa. This material achieves a very good balance between strength, toughness and wear resistance. The chromium content of the alloy provides good hardness permeability, and the molybdenum element imparts average hardness and high strength.SCM440 reacts well in heat treatment and it is easy to process under heat treatment conditions. This material provides many desirable properties such as good strength and wear resistance, excellent toughness, good ductility and resistance to high-temperature stresses.
Equivalent Grades: GB 20CrMo, JIS SCM420, ASTM 4118, DIN 25CrMo4. SCM420 are alloy steel with high hardenability, temper brittleness, well weldability, less cold cracking tendency, good machinability, and great cold plastic strain. SCM420 generally are used for the parts which need high wear resistance, such as gears, shafts, high-pressure pipes, all kinds of fasteners, and so on.
Equivalent Grades: GB 15CrMo, JIS SCM415, DIN 15CrMo5. SCM415 whose surface are processed through carburizing hardening treatment are used for the parts which need high toughness or wear resistance, such as cylinder piston, crankshaft, gears, pin, shafts and so on.