Pressure tests hydrostatic

Water resistance test methods include AATCC 127 (hydrostatic pressure test), AATCC 42 (impact penetration test), and AATCC 35 (rain test). In the hydrostatic pressure test, a sample is subjected to a column of increasing water pressure until leakage occurs. The impact penetration test requires water to be sprayed on the taut surface of a fabric sample from a height of two feet. The fabric is backed by a blotter of predeterrnined weight, which is reweighed after water penetration. The rain test is similar in principle to the impact penetration test. 

The hydrostatic-pressure test is performed on fabric mounted under the orifice of a conical weU. The fabric is subjected to increasing water pressure at a constant rate until leakage occurs at three poiats on the fabric s undersurface. The rating is the height of the water head ia centimeters above the fabric (AATCC Test Method 127 INDA Standard Test 80.4-92). 

Piping required to have a sensitive leak test shall be tested by the gas- and bubble-formation testing method specified in Art. 10, Sec. V of the ASME Code or by another method demonstrated to have equal or greater sensitivity. The sensitivity of the test shall be at least (100 Pa mL)/s [(10 atm mL)/s] under test conditions. If a hydrostatic pressure test is used, it shall be carried out after the sensitive leak test. 

All pressure vessels must pass appropriate hydrostatic testing before approval for service. For safety reasons, hydrostatic pressure testing is almost always recommended over a pneumatic test. The recommended... 

During construction it is impossible to avoid contamination of the piping with airborn ferrous particles from installation of structural steel and carbon steel piping components. If the stainless steel is kept dry, this may not be a problem. If the stainless steel piping is allowed to become wet, e.g., from a hydrostatic pressure test, the system should be tested with dry, oil-free air. If water is used, then provision must be made to thoroughly clean the system immediately after the hydrostatic pressure test. 

Theoretically, sutures can be eliminated (or a minimum of sutures) and a perfect bond can be provided by adhesives within 60 s to provide sufficient bond-strength while preventing the leakage of blood from vessels or skin, whereas sutures require a period of healing before a perfect bond is achieved. The bond can be seamlessly formed to withstand a hydrostatic pressure test comparable to human blood pressure within the same curing time ( 60 s). 

In industry, hydrostatic pressure testing of pipes is still widely used to assess their resistance to this type of failure. Typical results are shown in Fig. 6 [57, 58], where failure times of HDPE pipes are given as a function of the circumferential (or hoop) stress. At relatively high stresses, ductile failure is observed (stage I) although deformation is initially homogeneous, small local variations (arising from variations in the specimen thickness, for exam-... 

AATCC TM 127 and ISO 811 orEN 20 811 - Water resistance hydrostatic pressure test (former DIN 53886, Schopper- or Schmerber test)... 

In hydrostatic pressure testing, the pipeline is filled with water and pressurized to a specified test pressure that exceeds the operating pressure of the pipeline. If there are latent defects that are weak, a failure occurs. If failure does not occur then the line has been shown to be safe at normal operating pressure. 

Performance of the Sapphire NMR Tube. The tube and valve are sufficiently light weight and symmetrical that they spin and achieve a typical resolution of about 1 Hz. In hydrostatic pressure testing, the burst pressure of one tube was found to be approximately 14,500 psi, and it is therefore believed that operations up to 2000 psi may be carried out with a reasonable margin of safety. Obviously however, all due caution must be exercised and operator exposure to a pressurized tube must be avoided. It is as yet unclear whether extended use will eventually affect the performance of these tubes. In our hands, the tubes have been operated without incident, over a period of two years, from -140 to +150°C at nominal pressures up to 1200 psi. 

Since the seals were going to be exposed to very large hydrostatic pressures, a set of hydrostatic pressure tests of loading followed by unloading were also performed. The results from these tests indicated that the volumetric response of the material also included volumetric hysteresis during cyclic loading. One example of the volumetric response is shown in Fig. 11.15. 

AATCC 127-1985, Water Resistance Hydrostatic Pressure Test A test specimen, mounted under the orifice of a conical well, is exposed to 10 ml of a liquid and subjected to water pressure increasing at a constant rate until three points of leakage appear on its surface. The pressure level at which penetration occurred is given. (In this study, the test was arbitrarily stopped at 100 cm of water pressure.)... 

Results of the KC Blood Strike Through Test, the Impact Penetration Test, the Hydrostatic Pressure Test, the Biological Fluid Resistance Test (2 psi) were highly correlated (i.e., they differentiated between different types of gowns in a similar manner). 

Penetration pressure tests 2.5.1.2.1 Hydrostatic pressure test... 

ISO 811 1981. Textile fabrics - determination of resistance to water penetration -hydrostatic pressure test. International Standards Organisation 1981. 

F during hydrostatic pressure tests and or by + 60 F when the core is... 

The core critical curve is intended to provide additional margins of safety during core operation. The limit is defined as 40°F above the minimum allowable temperature for heatup or cooldown nor lower than the minimum temperature allowable for inservice hydrostatic pressure test, in accordance with paragraph IV.A.3 in Appendix G to 10 CFR 50. 

The reactor coolant pump pressure boundary is nondestructively inspected as required by ASME Section III for Class 1 components. The pump casing inspections include complete radiography and liquid penetrant or ultrasonic testing. The pump receives a hydrostatic pressure test in the vendor s shop and with the Reactor Coolant System. Inservice inspection of the pump pressure boundary will be performed during plant life in accordance with ASME Section XI. 

Additional tests on polymers mentioned in the literature include hydrostatic pressure tests on polyolefin [111] and PA [112] pipes, ageing and service life tests on polyolefin [113] and composite off-shore oil pipes, and general discussions on the mechanical properties of pipes [114,115]. 

Evaluation of Water Resistance (Hydrostatic Pressure) Test (NWSP 080.6.R0 (15) and ISO 9073-16 2007)... 

This technique cannot be used in the case of hot water pipes, where long-term hydrostatic pressure tests give better results [7b]. Oxygen is not usually regarded as an experimental variable in the study of polymer weath-erability since the oxygen concentration in the environment is essentially constant. However, the oxidation... 

Resistance to crack propagation for slow crack growth on notched pipes of wall thickness greater than 5 mm test method EN ISO 13479. It is expressed in terms of time to failure in a hydrostatic pressure test on a pipe with machined longitudinal notches in the outside surface. 

The two types of pressure testing are hydrostatic and pneumatic. Hydrostatic pressure testing with clean water is the preferred method. The test section should be completely filled with the test medium, taking care to bleed off any trapped air. Venting at high points may be required to purge air pockets while the test section is filling. 

After the structural test, the unit was removed from the test rig and hydrostatically pressure-tested at 200 psig on the shell side and 1000 psig on the tube side. These pressures were held by the unit for several minutes without pressure decay, which illustrated that the unit was still leak-tight. 

Freund, D., Mover, G., 1995. Hydrostatic pressure tests for the permeability-formation factor relation on crystalline rocks from the KTB drilling project. Surv. Geophys. 16 (1), 47-62. Freyburg, E., 1972. Der untere und mittlere Buntsandstein SW-Thtiringens in seinen gesteinstech-nischen Eigenschaften. Ber. dte. Ges. Geol. Wiss. A 17 (6), 911-919. Berlin. 

Class II. Hydrostatic pressure tests to measure the penetration of water as a function of pressure exerted by water standing on the fabric... 

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