... suitable for low speed and low frequency 4. Main components: Precision trapezoid screw pair and high precision worm-gears pair ... suitable for heavy load, low speed, low service frequency 7. Trapezoid screw has self-lock function, it ... Accessory parts: Motor, hand wheel, rubber bellows, steel cover, frequency inverter and brake. 9. Application: Metallurgy, construction, irrigation, chemical industry, ...