use caustic soda solution (Concentration 8-10%) Heat to 60℃ and soak the handpiece for 24 hours. cooler Use a high-pressure water gun (pressure>15MPa) to back-flush the copper tube. replacement All-oil sealing ring Avoid corrosion by residual cleaning agents.
[pdf] This can be done by wiping it down with a dry cloth and then spraying the cloth with compressed air to remove any debris on the surface. If there are stubborn stains or dirt, you may need to use some type of cleaners like soap and water or wax and grease remover.
[pdf] A rotary drilling rig is a construction machinesuitable for hole-forming operations in building foundation engineering. It is mainly suitable for sandy soil, cohesive soil, silty soil, fill layer, and silt layer, so.
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