Operator Requirements for a Safe Hose Assembly
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- Working Pressure (WP) should never be exceeded. Never leave liquids or gasses trapped in a hose with each end sealed or valves closed. Thermal expansion of some products may cause pressures to exceed working pressure.
- Always rate the Working Pressure of the coupled hose assembly by the lowest rated element (hose WP or coupling WP which ever is lowest). Try to identify all Critical Applications-those hazardous applications such as: high pressure (over 50 psi), petroleum products, chemicals or high heat (over 120°F).
- Only use the hose assembly for the service marked on the hose or for the service recommended in the printed literature.
- Have a hose inspection and test plan to ensure unsafe hose and/or worn or damaged couplings are removed from service.
- Test all hose assemblies as required every six months (or sooner) to insure the assembly is safe for continued use. (Use NAHAD, RMA, ASTM, OSHA, NFPA, LPGA or other regulatory agency recommendations for pressure testing along with these guidelines.)
- Educate hose handlers/users as to the conditions associated with unsafe hose; the operator is the last line of defense against spills and injuries. When in doubt, remove the hose from service. Maintain a Hose Inspection & Test Plan that requires a visual inspection prior to each hose use with pressure test.
- Always use appropriate Chemical Resistance Charts to verify that the chemical or product conveyed is compatible with the hose tube and alloy of the coupling. “Remember, the temperature and concentration of the chemical/product conveyed must not exceed the manufacturer’s recommendations.” It is recommended to always flush chemicals from hose after each use. Different chemical concentrations may cause damage to couplings or to hose. In some situations a hose assembly may be recommended for high (90%) concentrations but low concentrations (30%) may cause damage. After chemical use, cap the hose - prevent atmosphere & moisture from entering the hose.
- Always use a coupling made from material suitable for the application and product conveyed.
- Before each use always check the coupling for slippage. Look for misalignment or exposed cover from under the ferrule. If there are questions contact Apache 1.800.553.5455.
- In many cases the loading and unloading of Tank Truck Trailers develops hose pulsations as a result of the pumps used in these applications. This pulsation can cause the hose cover to wear very quickly. It is important to train the trailer operators to take care when using hose so that cutting, gouging and kinking can be avoided. In some cases a scuff-guard is added to the hose to protect the cover from abrasion. This extra guard will wear over time. Operators can add extra life to hose by simply rotating the hose so that cover wear is uniform. Should the scuff-guard be worn excessively, the operator should advise management to replace the scuff-guard. Hose life can be safely extended through this simple maintenance procedure (some users have improvised and placed mats or other protection under hoses in this type application to reduce cover wear).
- When measuring a hose for specific installation, it is important to remember that the tangent point for hose bending is at the end of the hose nipple portion inside the hose. It is to recommended to add a minimum of 6" to dimension ‘A’ shown. Always keep the bend radius of the hose within the recommended dimensions published for the specific hose.
- If there is the potential of a pull-away, buttressing of the piping system is a must. This will prevent piping fracture and make the hose the weakest link, causing it to separate. It is recommended to use a break-away devise along with dry-brake couplings for those applications with hazardous chemicals that may cause human injury or environmental damage.