Home / Resources & Training / Tips of the Trade / Proper Installation of Blast Couplings to Blast Hoses Proper Installation of Blast Couplings to Blast Hoses Posted in Abrasive & Water Blasting, Safety Tip: #4 Blast hose assembly procedure instruction guide Improperly fitted couplings are a serious hazard. It's always a good idea to refresh one's knowledge on the proper installation of blast couplings to hoses. Step 1: Cut the end of the blast hose square and clean (not with a hacksaw) so that the end of the hose can seal against the flange face - see (B) on the diagram at the top of page. A hose cutter tool can be used. If the hose is not perfectly square, there will be a gap between the hose end and the coupling lip which can lead to premature leakage and coupling failure. Step 2 (Optional): Run a bead of sealant compound around the inside of the coupling. This assists in creating a better, air-tight seal and will extend the coupling life. It will also act as a lubricant to assist with installation. Note: This does not act as a "glue". Step 3: Turn the fitting clockwise onto the hose until the hose end is firmly seated against the coupling flange face (B). Step 4: Wipe away any excess sealant compound from the inside of the hose. Step 5: Check there are no gaps between the end of the hose and the coupling lip. Step 6: Use the correct screw fasteners in all the available screw holes. Screws which pierce the inner wall of the blast hose will cause premature coupling wear. When being installed, screws will initially "push" the blast hose off the coupling wall before starting to "bite". It is important that the screws continue to be tightened until the hose has been pulled back up against the coupling wall (do not over tighten.) Check that the Blast Hose Bore (A3) is equal to or small than the Flange Bore (A2) and the Gasket Bore (A1). This will ensure the coupling does not wear prematurely, leaving the gasket unsupported and prone to leaks. For any hose with a bore greater than 1 1/4" (32mm), use Mega Max Large Bore Couplings. Do not pressurize the blast hose until the sealant has cured completely – this is usually around 24 hours. Once cured pressurize the hose and check for any air leaks using the soapy water method. If air is leaking at any point remove the coupling and refit. Leaking couplings will wear prematurely. DISCLAIMER: These instructions are provided as a guide only. Neither BlastOne International nor its associated companies are liable if these instructions are followed and an accidental coupling detachment occurs. Tip: #4 Share this Download pdf Related Links > Blast Hoses > Couplings > Cost vs Value for Blast Hoses > How Do You Know When Your Blast Hose Needs Replacing?