When specified, tubing shall be coated with a film of oil before shaping to retard rust. Should the order specify that tubing be shipped without rust retarding oil, the film of oils incidental to manufacture will remain on the surface. If the order specifies no oil, the purchaser assumes responsibility for rust in transit.
Unless otherwise specified, tubing may be coated with a rust retarding oil on the outside and inside surfaces, at the option of the manufacturer.
When specified, the hardness test shall be performed on 1% of the tubes
When the tension test is specified, one test will be performed on a specimen from one tube per 2000 ft (610 m) or less for sizes over 3 in. (76.2 mm) and one tube per 5000 ft (1520 m) or less for sizes 3 in. (76.2 mm) and under.
The yield strength corresponding to a permanent offset of 0.2 % of the gage length of the specimen or to a total extension of 0.5 % of the gage length under load shall be determined.
Various types of nondestructive ultrasonic or electromagnetic tests are available. The test to be used and the inspection limits shall be established by manufacturer and purchaser agreement.
When there are special requirements for steel cleanliness, the methods of test and limits of acceptance shall be established by manufacturer and purchaser agreement.
When tubing suitable for flaring is required, the manufacturer shall be consulted. When the grade and thermal treatment are suitable for flaring, a section of tube approximately 4 in. (101.6 mm) in length shall stand being flared with a tool having a 60° included angle until the tube at the mouth of the flare has been expanded 15 % of the inside diameter without cracking or showing flaws.
When the flaring test is specified, tests shall be performed on two specimens/5000 ft (1520 m) or less.