SWI Procedure API598

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API 598Hydro Test

PROCEDURE MANUAL

SPEC. NO. SW-P-25-01 ISSUED BY KH JUNG TEST PROCEDURE

ISSUED DATE 09/2006 TITLE APPROVED BY M.GILCHRIST

REVISION 00

SWI VALVE CO., LTD. A.P.I. 598 TESTING FOR METAL SEATED

GATE / GLOBE & CHECK VALVES SHEET 1 OF 6

1.0 PURPOSE

To define the factory test requirements for SWI metal seated Gate / Globe & Check valves. Standard testing comprises hydrostatic testing of the pressure envelope (body), backseat and seat tightness testing (hydrostatic and/or pneumatic) as applicable.

2.0 RELEVANT STANDARD The requirements set out in this standard are in accordance with the following National / International Standards, BS6755 Pt.1, pr EN 12266 Pt.1, API 598. The hydrostatic test pressures expressed in this standard comply with British Standard BS1560 and ASME B16.5 for flanges and fittings and ASME B16.34 for valves and API Std. 602 for Class 800 valves.

3.0 SCOPE This specification applies to metal seated Gate / Globe & Check valves including bellows sealed valves, tested according to API 598 Table 1A & 1B as described below. Valves specified for double block & bleed are not covered by this procedure.

NPS ≤ 4” & ASME Class ≤ 1500 NPS > 4” & ASME Class ≤ 600

NPS ≤ 4” & ASME Class > 1500 NPS > 4” & ASME Class > 600

Test Description

Gate Globe Check Gate Globe Check

Shell (Hydrostatic Body Test)

Required Required Required Required Required Required

Backseat (1)

(Hydrostatic Seat Test) Required(4) Required(4) N/A Required(4) Required(4) N/A

High Pressure Closure(Hydrostatic Seat Test)

Optional (2) Required (3) Required Required Required (3) Required

Low-pressure Closure (Pneumatic Seat Test)

Required Optional (2) Optional (2) Optional (2) Optional (2) Optional (2)

(1) The backseat test is required for all valves, except bellows seal valves, that have the backseat feature. (2) When an optional test is specified by the purchaser, the test shall be performed in addition to the required tests. (3) For power-operated and manually operated gear actuated globe valves, including non-return type globe valves, the high-pressure

closure test shall be performed at 110% of the design differential pressure used for sizing of the operator. (4) Unless stipulated otherwise by the purchaser, back seat test shall be the High-pressure (hydrostatic) closure test.

4.0 TEST REQUIREMENTS 4.1 General

Surface treatments of pressure containing valve components to prevent corrosion during storage prior to and during manufacture with a single primer coat (maximum 25 microns thickness) or phosphate treatment is acceptable provided these preservations do not hide any porosity.

4.2 Test Apparatus

Valves which have a split body design must not be tested on equipment which subjects the valve to externally applied loads which may affect the body joint sealing performance. Single piece bodied valves may be clamped.

4.3 Shell Test (Hydrostatic Body Test)

Every valve shall be subjected to a hydrostatic test of the body shell at 1.5 times the maximum permissible working pressure at 100°F (38°C), see Table 1. The body should remain tight for the test duration given in Table 2. The test shall show no leakage, no wetting of the external surfaces, and no

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permanent distortion under the full test pressure. No device shall be used in testing the valve that will reduce the stress in the body. The valve shall be set in the partially open position for this test, and completely filled with test fluid. Any entrapped air should be vented from both ends and the body cavity via either a) The upper test flange with the valve axis vertical. b) The body vent connection with the valve axis horizontal. After venting the body, vent plugs should

be replaced.

The gland or bellows and any body jointing shall be deemed as part of the pressure envelope. Where a bellows is fitted, the stuffing box packing & gland shall not be fitted. The valve shall then be brought to the required test pressure. All external surfaces should be dried and the pressure held for at least the minimum test duration. There shall be no visible leakage during the test duration specified in Table 2. Note: For valves with adjustable stem seals, leakage through the stem seals during the shall test shall not be cause for rejection, provided the stem seals are capable of retaining pressure at least equal to the 100°F (38°C) valve rating without visible leakage. If leakage is found, corrective action may be taken to eliminate the leakage and the test repeated.

4.4 Backseat Test (Hydrostatic Seat Test) When applicable (with exception of bellows seal valves), every valve shall be subjected to a hydrostatic test of the backseat at 1.1 times the maximum permissible working pressure at 100°F (38°C), see Table 1. The seat sealing surface / closure interface shall be free from oil, grease and sealant. The backseat should remain tight for the test duration given in Table 2. The test shall show no leakage, no wetting of the external surfaces, and no permanent distortion under the full test pressure. The valve shall be set in the fully open position with the packing gland loose or packing not installed. If the backseat test is performed after the shell test, the packing shall be installed and/or packing gland re-tightened after the backseat test. The valve shall be completely filled with test fluid. Any entrapped air should be vented from both ends and the body cavity via either a) The upper test flange with the valve axis vertical or via the stem with the packing removed. b) The body vent connection with the valve axis horizontal. After venting the body, vent plugs should

be replaced.

The valve shall then be brought to the required test pressure. All external surfaces should be dried and the pressure held for at least the minimum test duration. There shall be no visible leakage during the test duration specified in Table 2. If unacceptable leakage is found, corrective action may be taken to eliminate the leakage and the test repeated. If the valve is disassembled to eliminate the leakage, all previous testing must be repeated upon re-assembly.

4.5 High-pressure Closure Test (Hydrostatic Seat Test)

When applicable or specified by purchaser, every valve shall be subjected to a hydrostatic seat test to 1.1 times the maximum permissible working pressure at 100°F (38°C), see Table 1 for the test duration




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specified in Table 2. The seat sealing surface / closure interface shall be free from oil, grease and sealant. Depending on the valve design and size a “varying settling in period” is allowed. The allowable leakage of test fluid from the seat seal interface shall be according to those listed in Table 3. The test shall show no leakage through the disc, behind the seat rings or past the shaft seals. With the valve in the partially open position, the cavity shall be completely filled with test fluid and any entrapped air should be vented from both ends and the body cavity via either a) The upper test flange with the valve axis vertical. b) The body vent connection with the valve axis horizontal. The valve should be closed and the body cavity vent (where fitted) shall remain open. Gate Valve & Screw Down Non-return Globe Valve: The pressure shall be applied successively to each side of the closed valve with the other side open to the atmosphere to check for leakage at the atmospheric side of the closure. Globe Valve: The pressure shall be applied in one direction with the pressure applied under the disc (upstream side) of the closed valve with the other side open to the atmosphere to check for leakage at the atmospheric side of the closure. Check valve: The pressure shall be applied in one direction with the pressure applied behind the disc (down stream side) of the closed valve with the other side open to the atmosphere to check for leakage at the atmospheric side of the closure. If unacceptable leakage is found, corrective action may be taken to eliminate the leakage and the seat test repeated. If the valve is disassembled to eliminate the leakage, all previous testing must be repeated upon re-assembly.

4.6 Low-pressure Closure Test (Pneumatic Seat Test)

When applicable or specified by purchaser, every valve shall be subjected to an air seat test at a minimum gauge pressure differential of 4 to 7 bar (60-100 psig) for the test duration specified in Table 2. The seat sealing surface / closure interface shall be free from oil, grease and sealant. Depending on the valve design and size a “varying settling in period” is allowed. The allowable leakage of test fluid from the seat seal interface shall be according to those listed in Table 3. The test shall show no leakage through the disc, behind the seat rings or past the shaft seals. The valve should be moved to the half open position and any test fluid drained via either: - a) The lower test flange with the valve axis vertical. b) The body drain connection with the valve axis horizontal. Gate Valve & Screw Down Non-return Globe Valve: The pressure shall be applied successively to each side of the closed valve with the other side open to the atmosphere to check for leakage at the atmospheric side of the closure. Globe Valve: The pressure shall be applied in one direction with the pressure applied under the disc (upstream side) of the closed valve with the other side open to the atmosphere to check for leakage at the atmospheric side of the closure. Check valve: The pressure shall be applied in one direction with the pressure applied behind the disc (down stream side) of the closed valve with the other side open to the atmosphere to check for leakage at the atmospheric side of the closure.




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Check for leakage using either a soap film solution or an inverted ‘U’ tube with its outlet submerged under water. If the seat pressure is held successfully then the other seat shall be tested in the same manner where applicable. If unacceptable leakage is found, corrective action may be taken to eliminate the leakage and the seat test repeated. If the valve is disassembled to eliminate the leakage, all previous testing must be repeated upon re-assembly.

5.0 TEST LIQUID 5.1 Test Liquid

Hydrostatic tests shall be carried out with water at ambient temperatures, within the range of 41°F (5°C) and 122°F (50°C), unless the use of another liquid is agreed between the purchaser and the manufacturer. If water is used, it will contain water-soluble oil or rust Inhibitor. Potable water used for pressure test of austenitic stainless steel valves shall have a chloride content less than 30ppm and for carbon steel valves shall be less than 200ppm.

5.2 Cleaning

Austenitic and duplex stainless steel valves and valves made of 9% nickel alloy, shall be flushed with demineralized water (chloride content of 1ppm maximum) immediately after the hydrostatic test.

5.3 Drying After Hydrostatic testing, the valves should be blown through using dry compressed air, followed by a visual inspection for dryness. If moisture is still found, the above process shall be repeated until visually dry.

6.0 TEST GAUGES

Test bay gauges shall be calibrated at intervals not exceeding three months.

7.0 TEST CERTIFICATION When specified by the Purchaser, the manufacturer shall issue a BS EN10204 Type 3.1 test certificate confirming that the valves have been tested in accordance with the requirements of this specification.




REVISION 00



TABLE 1 – TEST PRESSURE (ASME B 16.34 & API Std. 602 for Class 800 Valves)

Class 150# 300#

CWP Shell Seat CWP Shell Seat Description Material psig Kg/cm2 Kg/cm2 psig Kg/cm2 Kg/cm2

A105, A350-LF2 285 32 23 740 80 59

A182-F5,F9,F11,F22 290 32 23 750 80 59

A182-F304,F316 275 30 23 720 78 57

A182-F304L, F316L 230 25 20 600 64 48

Class 600# 800#


A105, A350-LF2 1480 157 117 1975 210 153

A182-F5,F9,F11,F22 1500 159 117 2000 211 155

A182-F304,F316 1440 153 113 1920 204 150

A182-F304L, F316L 1200 127 94 1600 169 125

Class 1500# 2500#


A105, A350-LF2 3705 392 289 6170 653 478

A182-F5,F9,F11,F22 3750 396 291 6250 660 484

A182-F304,F316 3600 380 280 6000 633 465

A182-F304L, F316L 3000 317 233 5000 528 387

� CWP: The maximum allowable pressure at –20 OF to 100 OF (38°C).

TABLE 2 – TEST DURATION

MINIMUM TEST DURATIONS (Seconds) NOMINAL SIZE (NPS) Hydro Shell Test Backseat Test Hydro Seat Test Air Seat Test ≤ 2” 15 15 15 15 2 ½” – 6” 60 60 60 60 8” – 12” 120 60 120 120 ≥ 14” 300 60 120 120




REVISION 00



TABLE 3 – MAXIMUM ALLOWABLE LEAKAGE RATES

Gate & Globe Valves Check Valves NOMINAL

SIZE (NPS) Liquid Test(a)

(Drops Per Minute) Gas Test

(Bubbles Per Minute) Liquid Test Gas Test

≤ 2” 0 (b) 0 (c)

2 ½” – 6” 12 24 8” – 12” 20 40 ≥ 14” d e

3 scc x NPS /

minute.

700 scc x NPS /

minute

(a) For the liquid test, 1 millilitre is considered equivalent to 16 drops (b) For the liquid test, 0 drops means no visible leakage per minimum specified duration of the test. (c) For the gas test, 0 bubbles means less than 1 bubble per minimum specified duration of the

test. (d) For valves greater than or equal to 14” (NPS 14), the maximum permissible leakage rate shall

be 2 drops per minute per inch NPS size. (e) For valves greater than or equal to 14” (NPS 14), the maximum permissible leakage rate shall

be 4 bubbles per minute per inch NPS size.
