Screw gears, also sometimes called crossed helical gears, are helical gears used in motion transmission between non-intersecting shafts. The helical gears used in parallel beams have the same helix angle but opposite directions. For shaft angles other than the parallel, an arbitrary helix angle can be chosen. Assuming no profile shift, the intersecting angle of the shafts is the sum of the respective helix angles. Helical gears have point contacts and have lower efficiency than parallel or perpendicular shaft gears, and cannot transmit heavy loads.
Screw Gears: Technical Information
HZPT stock screw gears come in modules 1 ~ 4, 10 to 30 teeth, and 4 materials: S45C, SUS303, CAC702 (formerly A BC2), and MC nylon.
| Catalog No. | Module | Material | Heat Treatment |
Tooth Surface Finish |
Precision JIS B 1702-1: 1998 |
Secondary Operations |
Features |
|---|---|---|---|---|---|---|---|
| SN | 1 ~ 4 | S45C | — | Cut | N9 | Possible | Popular screw gears. Additionally, gear tooth induction hardening secondary operations can be performed. |
| SUN | 1 ~ 3 | SUS303 | — | Cut | N9 | Possible | Suitable for food machinery due to SUS303’s rust-resistant qualities. |
| AN | 1 ~ 4 | CAC702 (Al BC2) |
— | Cut | N9 | Possible | made of aluminum bronze, these gears have excellent wear resistance. |
| PN | 1.5 ~ 3 | MC901 | — | Cut | N9 | Possible | Light-weight products are made of MC Nylon and can be used without lubrication. |
Selection Hints
Please select the most suitable products by carefully considering the characteristics of the items and the contents of the product tables. Before the final selection, it is also essential to read all applicable “CAUTION” notes. Since screw gears come in the right- or left-hand helix, include the letter “R” or “L” in the catalog number when you order.
1. Caution in Selecting the Mating Gears
Screw gears are used for offset shafts. Whether the shafts are paralleled offset or skewed offset depends on the helix hands of the mating gears.
| Direction of Shaft | Arrangement of Helix Hands |
| Skewed Shafts | RH-RH or LH-LH |
| Parallel Shafts | RH-LH |
our service
1. According to the customer requirements of the strength and performance of the product, we will choose different compressive forces of steel.
2. Our engineers using professional drawing software, will design a more reasonable size and better product performance.
3. We can customize the product according to the customer’s needs so that the gear can perform the best in different working conditions.
4. To ensure that the quality of products can be controlled, we use professional measuring tools for quality testing at every step.
