1.1 Units of measurement

1.5.1 Information in the standard АPI 5CТ is given according to the International system (Si-system) as well as according to the 115C system of units used in the USA. During the preparation of an order, it is assumed that there is only one system of units in use without the simultaneous expression of data in the other system.

The products are manufactured according to the specifications expressed in one of these systems of units and are considered equivalent and completely interchangeable. Therefore, compliance with the requirements of this International Standard, expressed in the units of one system, ensures compliance with the requirements expressed in another system.

1.5.2 The standard API 51_ uses the units of measurements of the Si-system as well as standard American units of measurement. Only one system of measurement must be used in respect of a separate order, unless otherwise stipulated, regardless of the other.

For the data expressed in the Si-system units, the comma is used as a decimal separator in decimal fractions and the space is used to separate thousands. For the data expressed in ordinary American units, the dot (in a line) is used as a decimal separator; the space is used to separate thousands.

2 Requirements for finished pipes

2.1 Requirements for the finished pipes on key parameters (outer diameter, wall thickness, weight, angle of flexure) are shown in Table 2.1. Minimum and maximum values of the outer diameter and wall thickness of pipes according to Standards API 51_, API 5CT, AZTM A106/A106M, AZTM A53/A53M are shown in Tables 1, 2, 3 and 4 of Annex C. Limits of angles of flexure (depending on the length of pipes) according to Standards API 51_ 5CT and API are shown in Table 5 of Appendix C.

In accordance with the requirements of Standard API 5CT the sizes of coupling blanks, including the tolerable limits of the diameter and wall thickness and straightness requirements for pipe coupling blanks shall be agreed upon during the process of ordering between the customer and the manufacturer.

2.2 Length of pipes

2.2.1 according to Standard АРI 5CT

Tubes are supplied in lengths given in Table 2.2

* The deviation for a carload is not applicable for orders less than a carload consignment weighing 18,144 kg. For any carload weighing 18,144 kg or more, shipped to the final destination without reloading or unloading of the car, the deviation must apply to each car. For any order, consisting of a carload weighing 18,144 kg or more and shipped by rail not to the final destination, the carload deviation should be extended to the entire order, but not on individual carloads.

** Upon the agreement of the customer with the manufacturer a full range of lengths of tubing for range 1 can be 6.10 m - 8.53 m.

*** Upon the agreement of the customer with the manufacturer the maximum length can be increased up to 13.72 m.

Sweeping-up of casing pipes made in accordance with the requirements of Standard API 5CT must be carried out in accordance with the requirements of TI-NTZ Tr4-07-2007 (or instructions published to replace it) and MI-NTZ-IL-63-2007 (or techniques published to replace it).

2.2.2 According to Standard АРI 51

If the customer does not indicate the random length of the supplied pipes, it must be within the limits specified in Table 2.3. Approximate length must be within the limit of ± 500 mm (20 inches).

2.2.3 According to Standard AZTM A106/A106M.

Length of pipes is specified in the order. The following pipes can be ordered:

- single random length - from 4.8 m to 6.7 m (16 * 22 feet) including up to 5% with the length of

3.7          + 4.8 m (12 - 16 feet).

- double random length - a minimum of 6.7 m (22 feet), minimum average

10.7 m (35 feet), including up to 5% with the length of 4.8 -4- 6.7 m (16 + 22 feet).

2.2.4 According to Standard AZTM A53/A53M, unless otherwise specified in the order:

for the pipes with the weight lower than ultraheavy - from 4.88m to 6.71m (16-22 feet), including up to 5% of the pipes can have a length of 3.66m to 4.88m (12 + 16 feet);

for ultraheavy and heavier pipes - from 3.66 m to 6.71 m (12 +22 feet), including up to 5% of the pipes can be supplied in lengths from 1.83 m to 3.66 m (6 + 12 feet);

-for ultraheavy and lighter pipes, ordered with double random length - the length should not be less than 6.71 m (22 feet) with a minimum average length of pipe in the order of 10.67m (35 feet).

When the required length of pipes is greater than single random length with wall thickness greater than that of heavy-duty pipes it must be specified in the order.