Except for material for bolting, impact test results for full-size specimens shall meet the requirements of Table 3。

Where the material specification for the pipeline and/or piping design standard requires impact values to be higher than those shown in Table 3, the higher values shall apply。

Impact test results for bolting material shall meet the requirements of ASTM A320。

Impact values for full-size specimens of duplex or super duplex stainless steels shall be as follows:

a)average of three specimens: 33 ft lb (45 J) minimum; b)no single specimen less than 26 ft lb (35 J); c)Impact test temperature shall be –50 °F (–46 °C)。

If a test fails, then a retest of three additional specimens removed from the same TC, with no additional heat treatment, may be made, each of which shall exhibit an impact value equal to or exceeding the required average value。

Table 3—Minimum V-notch Impact Requirements (Full-size Specimen)

Specified Minimum Tensile Str

Average of Three Specimens

Single Specimen

KSI Mpa ft lb joules ft lb joules

≤85 ≤586 15 20 12 16

85-100 586-689 20 27 16 21

>100 >689 25 34 19 26

5。7Bolting

Bolting material shall be suitable for the specified valve service and pressure rating。

Carbon and low-alloy steel bolting material with a hardness exceeding HRC

35 (HBW 321) shall not be used for valve applications where hydrogen embrittlement can occur。

Hardness limits for other bolting materials shall be by agreement。

5。8Sour Service

Materials for pressure-containing and pressure-controlling parts and bolting for sour service shall meet the requirements of NACE MR0175 or ISO 15156 (all parts) or NACE MR0103。 Purchaser shall specify which standard is to be used。

5。9Drain Connections

Threaded plugs shall be compatible with the valve body material or made from a corrosion-resistant material。

5。10Heat-treating Equipment Qualification

Heat treating of pressure-containing and pressure-controlling parts and associated TCs shall be performed with “production-type” equipment conforming to requirements specified by the manufacturer。 "Production-type" heat- treating equipment shall be recognized as equipment that is routinely used to process production parts。

All heat treatment for mechanical properties shall be performed using furnaces that are calibrated in conformance with Annex F。 Post-weld heat treatment (PWHT) shall be performed with heat-treat equipment conforming to requirements specified by the manufacturer。

Furnaces shall be calibrated and surveyed per 8。2。5。

Records of furnace calibration and surveys shall be maintained for a period not less than five years。

Bibliography

[1] API Specification 6DSS, Specification for Subsea Pipeline Valves [2] API Specification Q1, Specification for Quality Management System Requirements for Manufacturing Organizations for the Petroleum and Natural Gas Industry