There are settings for both gas pressure and flow rate. These can vary depending upon the welding position, metal type/thickness, type of gas used, and conditions (wind, drafts etc.) My welding instructor told us that 20-20 is a good place to start (20 psi, 20cfm flow).
It is the one lettuce that doesn't have a lot of Vitamin K. One cup of iceberg lettuce contains only about 13 micrograms (mcg) of Vitamin K. This is a low amount and should be safe for you to use as part of your diet while on CoumadinÂ® (warfarin). Thanks for writing, Timothy S. Harlan, MD, FACP. Dr. Gourmet.
The most important nutrients in lettuce are vitamin A and potassium. The vitamin A comes from beta carotene (beta-carotene is converted to vitamin A in the body), whose yellow-orange is hidden by green chlorophyll pigments. Lettuce, except iceberg, is also a moderately good source of vitamin C, calcium, iron and copper.