Views:1 Author:Site Editor Publish Time: 2019-06-03 Origin:Site
We received an inquiry from a Russian customer today, which mentioned the need to purchase some welded pipes of ASTM A671 GR CC60 CL22. Below is the original picture of the customer's inquiry, see the following figure.
STM A671 GR CC60 cl.22 inquiry
The friend that often deals with steel tube, should not strange to this material steel tube. Yes, this kind of steel pipe belongs to the category of low alloy pipe. All known as low temperature electric melting welded steel pipe.
Below, we will analyze the nouns ASTM A671 GR CC60 CL22 one by one.
ASTM stands for American Society for Testing and Materials. In other words, the standard that they set is very high. Their official website is https://www.astm.org, which is a bit authoritative, but unfortunately it costs us $to download the original documents.
A671 is the specific material standard, which represents the low temperature electric welded steel pipe. Note that the steel pipes specified in this standard specifically refer to welded steel pipes.
Gr is a contraction of grade; CC60 is the material brand, in this case carbon steel.
CL22 is material level. For example: c 32 requires steel tube to be normalized, and c 22 requires stress relief heat treatment.
W/S2 AT -46℃.
Where, W/S2 refers to electric welding steel pipe; -46℃ is the operating temperature. W/S2 at-46 ° c -- - in SEI's code for materials, it is explained as follows: "low-temperature impact experiment of this brand AT -46 ° c"
Ok, name breakdown, let's summarize.
Application of ASTM A671 Gr CC60 electric welding pipe: mainly used for oil and natural gas transmission pipeline, whose specification is marked by outer diameter * wall thickness. There are two kinds of electric welding pipes: single-side welding and double-side welding. The welded pipes should be tested by hydraulic pressure, and the tensile strength and cold bending performance of the welding seams should meet the requirements. Manufacturing grade from cl10-43, heat treatment, stress relief treatment, normalizing treatment can be produced according to customer requirements.
In this act as an example, let us have an intuitive understanding of this kind of steel pipe.
Jiangsu LNG receiving station project is one of the first LNG receiving station projects started by CNPC. The high-pressure and low-temperature external transmission pipeline in the receiving station adopts A671 gr.cc60 low-temperature steel pipe produced by German EEW company.
The A671 gr.cc60 low temperature electric melting welded steel pipe produced by EEW company is made of A516 gr.60 medium and low temperature pressure vessel carbon steel plate, which is the nickel free low temperature steel material recommended by ASME code, with the minimum service temperature of -18~60°C.
According to the principle of matching chemical composition and mechanical properties of materials, tig-80ni1 welding wire and W506Ni welding rod are selected as welding materials to ensure good weldability and low temperature toughness of welding joints.
How to do preheating before welding, slow cooling after welding heat preservation, post-welding heat treatment, and various tests, we do not elaborate. Go straight to the final effect.
By adopting reasonable welding and heat treatment processes, the construction contractor successfully completed the welding of high pressure and low temperature natural gas external main pipeline in jiangsu LNG receiving station, with a total of 105 welding joints and 877 films, the qualification rate of the first ray inspection reached 96.4%, and the ultrasonic inspection of the filling layer of fixed mouth was 15, all of which were qualified. The external pipeline of the receiving station has been put into operation for more than two years without any problems.