Checking welds

Respectively, which rays are used for sterilizing foods, detecting smoke, controlling the thickness of paper and checking welds ... 

Radiography using x- or gamma-rays is well established and is a routinely used technique of non-destructive quality control. It is applied for checking welds, castings, assembled machinery (such as jet engines), and in ceramics. 

Check welded points near motion machine, such as centrifugal atomizer, hammer, etc. 

Ionizing radiations are now widely used in the construction industry to check welded joints in... 

Check bevel, check welding parameters, pipe rotation (always compatible with the position of the longitudinal welds which must be spaced a certain length) or application of shims on the internal clamp expanders to reduce misalignments. 

No firm conclusion should be drawn from the above data, through the observed pattern deserves attention. The AE activity observed on the SH header can originate from the weld, but could be due to other causes, namely to the settlement of the hanger. Ultrasonic inspection of the weld at regular intervals checks whether any sizeable change in NDT response from the weld has taken place. 

Besides large-diameter pipes, ultrasonic testing is used for checking the welded joints of drill bits, components of wind-driven electric plants, welded joints of light alloys and non-metallic materials, for an integrated inspection of various objects. A range of training aids developed at the Institute allows the operators to be trained effectively. 

Agreement on the NDE plan will be dependent on the extent and relevance of theschedule. Under the amendments proposed to the Rules Surveyors will check that structurally significant welds are included in the shipyard s quality control programme. When agreement has been reached the Surveyor will endorse the plan. 

Weld inspection duties of personnel responsible for judging the quahty of welding with regard to specifications have been treated (15). Some of these duties involve the visual inspection of welds to determine if they are of the proper size, location, and type and are free of defects. Specifications of materials used must be checked, as must equipment and procedures. 

Tlie indi ddual cells are assembled into batteries after a leakage test to check for faulty welding joints in steel containers or cracks and improper seals in the plastic encased cells. Cells that are to be delivered without electroltye are emptied after the fomiation cycles. Tlie steel-cased cells hav e to be separated by mechanical means to prevent intercell shorts and are often assembled into wooden crates. Tlie cells in plastic cases can be cemented together or strapped with tape. 

Rules for the welded fabrication of pressure vessels cover welding processes, manufacturer s record keeping on welding procedures, welder qualification, cleaning, fit-up alignment tolerances, and repair of weld defects. Procedures for postweld heat treatment are detailed. Checking the procedures and welders and radiographic and ultrasonic examination of welded joints are covered. 

The sheet may also be inspected for the quality of welding and checked for pin-holes by a weld-hole detector before it is finally cut into lengths or wound onto rolls. 

We have seen that welds can be very weak in a fatigue situation, and we would be wise to check that the modified weld in Fig. 28.7 is adequate for the job. Although it is difficult to spot immediately, the weld is in fact subjected to large bending stresses (Fig. 28.8). These can be calculated as follows. 

Increase shaft diameter and decrease end plate. thickness Increases / and decreases t in eqn. 28.10. Would need 250 mm diameter shaft + 1 5 mm thick end plate very heavy and expensive. Would still need to check plate-shell weld. 

If the control valve size is critical to the overpressure protection of the downstream equipment, and must not be increased, then this is clearly noted in all relevant documentation (specification sheets, flow diagram, operating manual, etc.,) and a warning notice plate is welded to the valve body. In such cases, an actual check of the valve installed or purchased should be made during the startup review. 

Instructions for erection and detailed welding specifications with recommendations for checking of site work,... 

Many companies now insist that if use of the wrong grade of steel can affect the integrity of the plant, all steel must be checked for composition before use. This applies to flanges, bolts, welding rods, etc., as well as the raw pipe. Steel can be analyzed easily with a spectrographic analyzer. Other failures caused by the use of the wrong construction material are described in Section 16.1. 

In the Sundyne Canned Motor design, the entire outside of the motor is enclosed in a secondary leakage containment shell or can. Primary leakage protection is provided by corrosion resistant liners which are seal welded and 100% leak checked to assure that pumped fluid does not contact the stator windings or rotor core. There is no shaft protrusion to seal and thus no seals to leak. 

Check freshly blasted surface for steel imperfections, laminations, weld spatter, etc. and ensure that any necessary metal dressing is carried out. 

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