An increasing number of road construction contractors are utilizing steel plate shot blasting machines for rust removal. With proper maintenance, the service life of these machines can be effectively extended. How should one correctly maintain a steel plate shot blasting machine?
1. Inspect wear-resistant parts within the mobile shot blasting machine for wear and replace them promptly.
2. Properly lubricate moving parts; check which parts require lubrication before startup. Do not over-apply lubricant.
3. When installing or replacing blades, ensure the weight difference between blades does not exceed 5 grams.
4. Before shutting down, carefully verify that all operations have been properly terminated.
5. Check the separator's filter screen for accumulated debris and clean it promptly.
6. Inspect dust collection ducts for air leaks.
7. Listen for any abnormal noises while operating the machine.
8. Check that there is a sufficient supply of shot media before each startup.
9. The quality of the steel bridge deck must comply with specifications or design requirements.
10. The steel surface (including the base of protective walls) must be smooth, clean, and dry. It must be free from hollow spots, looseness, honeycombing, pitting, loose mortar, loose dirt, mold release agents, and oil stains; surface strength must meet specification requirements.
11. Raw materials entering the site must have undergone sampling inspection.
12. Ensure a sufficient workforce, containers, and other tools are available.
13. Use equipment capable of simultaneous laitance removal and dust collection, featuring a self-propelled drive system and a closed-loop shot recovery mechanism. Set the shot blasting machine to speed gear 2–3, with an operating speed of 5–10 m/min and S390 shot media. After establishing the blasting process parameters, perform large-area shot blasting and ensure thorough cleaning upon completion.
14. The shot blasting process must be continuous. If blasting stops for any reason, reverse the machine 30 cm before resuming operation. After the machine passes over a section, promptly inspect the overlap area for quality and touch up any missed spots.
15. Angle grinders may be used to level specific areas of the steel bridge deck and protective walls. Ensure there are no noticeable grooves or indentations; edges should be straight and flat to guarantee effective adhesion of the waterproofing layer.
16. Shot-blasting roughness must meet specifications. Excessive roughness leads to high primer consumption and extensive remedial work, while also compromising bond strength; conversely, insufficient roughness results in poor adhesion. Control standards rely on visual inspection to ensure no loose debris remains, with roughness levels adhering to the SP3 standard.
17. Beams feature sloped ends and sides, areas where shot-blasting machines are prone to media leakage and significant material loss. To control costs, the blasting team must manually collect and recycle the media; media loss should be kept within the 10%–20% range. Blasting right up to the edges-without allowing media to spill over-can significantly reduce the need for subsequent grinding, thereby saving time and minimizing material waste.
The above points cover the operational precautions and basic maintenance details for steel plate shot-blasting machines.
