Questions about blast cleaning?
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The installation is scheduled to be purged by blasting for the first time; can asbestos gaskets be used for sealing during the purging process? Another issue is how to secure the asbestos gasket; it’s not possible to attach it in most areas where flanges are present. What should be done?
It can be used; the steam flow can be controlled quickly by using the ball valve at the front
Asbestos pads can be used for purging, as well as kraft paper. The thickness of the asbestos pad can be 1–3 mm; a “cross” or “plus sign” pattern can be marked on the asbestos sheet. The blasting pressure generally ranges from 0.3 to 0.4 MPa. If the pressure is too low, the number of blasts required increases and it becomes difficult for the blast disc to break; if the pressure is too high, it is unsafe and can lead to injuries. The pressure depends specifically on your purging requirements. Small flange holes can be fixed by drilling holes in the asbestos board and using screws on the flange ； It can also be secured with other things. When we carried out blasting and purging on the equipment, I was targeting the medium-pressure steam pipelines; it was a terrible experience...
Here, we use asbestos boards with flanged openings directly; the pressure is more or less the same. A suitable choice is made based on the pipeline layout of the installation. It’s very harmful to your ears during blasting; make sure to wear protective gear such as goggles and earplugs.
Asbestos boards are generally installed behind valves, right? But this place has pipelines connected to it on both the front and back – what should be done if flanges can’t be installed?
After the installation is completed, no blasting and purging is carried out. Which pipelines require such blasting and purging? What are the relevant standards?
Our construction phase has passed the rainy season; basically all pipelines have been treated with blasting. The raw materials, reaction systems, compressors, as well as the medium-pressure steam systems, have also undergone testing. The target accuracy for the raw materials is not high
For selecting the blasting points, can you draw a simple diagram? We carry out blasting in segments over there~~~~
Find a matching flange or cut one from iron plate!
Should blasting and purging be done before pipeline installation, or wait until after construction is completed and work is set to begin?