... steel is treated by carburization for improving its surface hardness and wear resistance.2. Stainless steel is used on the surface ... to reach the standard of food hygiene.3. Saving labour and covering small land4. The oil can meet the standard of ... , such as, peanuts, sesame, vegetable seeds, soybean, oil sunflower, flax, coconut etc.6. Squeezing once with 3rd grade SpecifiationModelScrew oil pressZL ...