A leak in a high-pressure hose can create a dangerous situation depending on how it is used. Since the hose likely maintains a pressure of 800 pounds per square inch or higher, you cannot repair the hose with tape. You must splice it by cutting the hose at the leak and installing a coupler designed for high-pressure situations. If the high-pressure hose is for industrial use, check with OSHA guidelines to determine whether you are allowed to couple the hose or if you must replace it.
Turn off the equipment pressurizing the hose and release pressure from the hose with the pressure-relief valve. This will differ depending on your application so follow owner's manual safety shutdown guidelines for turning off and removing pressure.
Locate the hole in the hose and cut out the damaged section with a razor blade, hose cutters or hacksaw, depending on the thickness of the hose. Make sure each side of the hose remains square after cutting.
Apply several drops of soapy water to each end of the coupler to make it easier to put the coupler onto the hose. Two of the most popular types for high-pressure hoses are compression couplers and barbed couplers.
Slide the barbed coupler halfway into the hose. If you use the correct barbed coupler, you will need to grip the coupler with pliers to push it into the hose. When installed, the outside diameter of the hose should not expand very far. Slide the clamps onto the hose. Press the other end of hose onto the other end of the coupler. Both ends of the hose must touch if possible. Place the clamps in place and tighten them. The process for tightening the clamps will vary depending on the model you use but usually the clamp is cam driven and requires a screwdriver for tightening. If you are using a compression coupler, move to the next step.
Slide the compression coupler onto the hose. The compression coupler has a shaft that slides inside the hose and a shaft that slides over the outside of the hose simultaneously. Slide the hose in place until it bottoms out in the coupler and then connect the other hose to the other side of the coupler in the same manner. Turn each end of the coupler with a wrench to tighten the coupler onto the hose. As you tighten the hex nut on each end of the coupler, it compresses the coupler onto the hose and eliminates leaks.