Steel test certificates

The manufacturers had provided a test certificate stating that the valve was made from 304L steel. 

A knowledge of steel composition is essential for selecting the appropriate welding diagram. Where test certificates are available for the material to be welded, these should be consulted to determine the CE appropriate to the steel. Where this is not available, the specification for the steel, whether it be a national or international standard or a maker s specification, is helpful and increasingly these may provide data on the maximum CE values for particular grades. 

In cases where the test certificate, or steel specification, only gives data on carbon and manganese contents, information for C Mn steels suggests that an appropriate allowance for residual alloying elements to be added to the CE would not exceed 0.03%. For steels produced by an all-scrap route, this may be too low values as high as 0.08% have been found necessary, while 0.05% is a more typical value. 

High-pressure piping shall be of stainless steel 316 L and Low-pressure piping shall be of a material which wiU not contaminate the treated water (CPVC with test certificates). 

Thickness of shell should not be less than 12 mm. Boiler quality steel should be used since these units run at high internal temperature for long time continuously. Internal lining details (e.g. type of insulating and refractory bricks used, their alumina percentage, thickness of layer, castable refractory, expansion joints provided. (Vendor to submit copies of their test certificates giving chemical analysis, refractory properties, thermal conductivities if asked for by the purchaser. The expected maximum temperature at outer surface of the shell should not normally exceed 60—65 °C.)... 

For example, if the subsoil is unfavourable (low bearing capacity, etc.), but steel plate is obtainable at relatively low cost, it will be possible to build inexpensive ciinker storage silos by means of the rational "spiral" method of erection. The construction material should be weather-resistant steel (grade WT52-III conforming to EW087-70, acceptance under test certificate 50049-3.1 C) (Fig. 5). Steel silos of appropriate construction require no painting and are therefore virtually maintenance-free. 

Mechanical Properties. The mechanical properties used for design shall be the minimum values allowed by the applicable material specification or shall be the minimum values determined by the manufacturer in accordance with the test procedures specified in ASTM A370 Methods and Definitions for Mechanical Testing of Steel Products, or by mill certification for mill products. The yield point shall be used in lieu of yield strength for those materials exhibiting a yield point. Yield strength shall be determined at 0.2% offset. 

The Standards, Measurements and Testing Programme of the European Commission launched a few years ago a project dealing with the development and, ultimately, the production of air filters realistically exposed to welding dust occurring during stainless steel welding (Christensen et al. 1999). This project resulted in the production and certification of a batch of 1100 filters for the Cr (VI) content (40.16 0.60 pg/g dust) (CRM 545). In addition, the total leachable Cr content ( 39.37 1.30 pg/g dust) was certified as a means to check for total Cr recovery. 

The steels used for this pressure range are beyond the scope of the national codes and have been approved by an individual testing and certification procedure. 

Standard ASTM potentiodynamic anodic polarization plot for certification of potentiostat performance. Type 430 stainless steel in 1 N H2S04at 30 °C. Scan rate of 600 mV/h. Test curve is to lie within the shaded region. Redrawn from Ref 27... 

Are forged from hardened and tempered high-tensile steel and are rated according to their SWL A range of types are available including those with a safety latch as shown in Fig. 19.10. Form and dimensions are set out in BS EN 1677-5 which states that all hooks shall be free from patent defect and shall be cleanly forged in one piece. After manufacture and heat treatment each hook shall be subjected to a proof load. After proof testing each hook is stamped to allow identification with the manufacturer s certificate of test and examination. 

MOC Ordinary mild steel (e.g. 1.S.2062 or its international equivalent) should not be allowed. Certification for MOC mnst be obtained. Samples of MOC must be tested in approved laboratories. 

---