An oil leak occurred due to the rough seat surface of the flare connection, and because it was an old model, there were no replacement parts and it was not possible to deal with it by replacing parts, but we were able to repair the oil leak using this flare packing.
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Buy as many as you need at retail to prevent flare leaks
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We purchased for oil coolers of motorcycles. It can be repaired at a lower cost than the parts in the shop.
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This time, I used it as a part of the air compressor. It was a good feeling.
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I was worried about the degree of vacuum even with careful flaring, so I installed it with insurance. There is a peculiarity in the shape, and I dealt with it with a little forcible installation, but it is quite good.
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Introduced to prevent leakage of flared connection of refrigerant piping. With proper flaring, I didn't feel the advantage of introducing this product.
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When reusing old air conditioner piping, use 2 minutes and 2 minutes each. Since the piping is brass, gas leaks are a concern unless a soft copper washer is used. I will buy it again because I can rest assured that it is a much cheaper investment than buying a new pipe.
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I don't use it because I don't have a chance to use it. I don't know.
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There is an opinion that the copper flare packing is meaningless because the flare itself is copper, but by inserting the packing in between, there is no need to be sensitive to flare processing and it adheres neatly. This is because copper is very soft and has excellent adhesion. I think that flare lock is better for applications, but I hear that the sealing material cracked due to over-tightening and leaked from there. It seems that the copper flare packing should be tightened to the specified value with a torque wrench and then lightly squeezed again with a monkey (about 30 degrees) for better adhesion. But at first I was impatient without knowing it). If you use this packing, the nut will not be reusable because the packing will be inserted in the back of the nut if it fails.
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It is better to pack it a little more tightly, because it is a part that corresponds to precision parts
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