NAHAD Hose Safety Institute - Hose and Coupling World

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The operators of any hose are a company's last line of defense against spills resulting from damaged hose. Companies sho
ASSOCIATION EXTRA

NAHAD Hose Safety Institute Proper hose assembly management & the importance of visual inspections

Damaged, separated or pulled back cover

Properly crimped fitting

Poorly crimped fitting

Improperly banded hose - buckles need to be staggered

Edited by Debbie Mitchell, NAHAD Standards Manager

The Association for Hose and Accessories Distribution’s (NAHAD’s) Hose Safety Institute© provides a forum for distributors, manufacturers, suppliers, end users and industry organizations to support and promote hose assembly safety, quality and reliability. This article represents an ongoing effort to document best practices for ensuring the safety and reliability of hose assembly applications. Many applications have the potential of being “high risk” if not managed properly, with resultant environmental and safety considerations. It is necessary to ensure worker safety and environmental stewardship, in part through the use of a comprehensive hose management policy, one portion of which focuses on in-service considerations. The recommended service life of a hose assembly is dependent on the care it receives, the application it is being used in, the material being transferred, cleaning processes and a thorough inspection program. This article focuses on in-service hose assembly inspection programs and provides guidance for companies wishing to better manage the hose assemblies in their operations. Recommendations for proper hose use and care: Inspections A Hose and Fitting Maintenance Program is critical to maintaining a safe functional hose system and will reduce equipment down time and maintain peak operating performance. Hoses should be inspected and pressure-tested in-house or by a third party, prior to placement into service and whenever a defect is suspected. For high risk applications, inspections and pressure testing should be conducted annually, at a minimum. A visual inspection should be conducted prior to each use and at the end of

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job use. Frequent hose re-testing is also a recommended procedure to ensure the safe continued serviceability of hose assemblies. The inspection process should include: • Visual inspection • Pressure testing - New hoses and hoses meant for re-certification should be pressure tested at 1.5 times the maximum allowable working pressure, for a minimum of 5 minutes, or in accordance with manufacturer requirements. It is important to note that the maximum allowable working pressure for a hose assembly is dictated by the component of the assembly (hose, fitting, etc.) with the LOWEST pressure rating. - Hose assemblies should be inspected and tested immediately after the hose is subjected to abnormal abuse. Such abuse can include severe end pull, flattening, crushing or sharp kinking. Any hose that has been recoupled should be proof-tested and inspected before being placed in service. • Inspection results documentation - Documentation including date, hose specifications, pressure test results and visual inspection observations should be maintained More on visual inspections The operators of any hose are a company’s last line of defense against spills resulting from damaged hose. Companies should implement training programs that educate operators on what to look for, before the hose is ever placed into service. The operators should be trained to always err on the side of safety and whenever in doubt, remove the hose from service.

Hose & Coupling World, March/April 2016

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Blisters – soft or bulging hose

Cover gouging

Wear

Weathering / dry rot

Compromised reinforcing wires

Loose hose tube near the coupling

Loose hose tube (de-lamination) near the coupling

Discolored hose tube

Internal inspection Small ID hoses are difficult to visually inspect without a special bore camera. As the IDs get larger, an internal inspection becomes more feasible. Hoses with IDs of 2” and larger offer the ability to see several feet into the hose. What can be seen throughout this visual segment is generally indicative of the status of the remainder of the hose. The hose and fittings should be visually inspected for: • Leaks at the hose fittings or in the hose • Damaged, separated or pulled back covers • Cracked, damaged, deformed or badly corroded fittings • The state of the crimp (if applicable): a good crimp has part of the hose coming out of a ‘hole’ in the crimp. That tells you the hose has been crimped all the way up to the top of the fitting. If you can’t see the hose then you don’t know how far up the hose has been inserted and crimped. • Other signs of significant deterioration such as: - Blisters - Compromised reinforcement where the wires are exposed and show signs such as being unwrapped, broken or corroded - Dents, twists or kinks - Discoloration of color-coded hose cover

• Fitting thread and seat condition • Verify condition and seating of gaskets • Verify test date and that pressure is in conformity with requirements for the application

Convenient Visual Inspection Checklist Visually inspect hose before each use. In the event of any of the following conditions, immediately remove hose from service External Inspection: ¨ Evidence of leaks at the hose fittings or in the hose

¨ Damaged, separated or pulled back covers (de-lamination) ¨ Cracked, damaged, deformed or badly corroded fittings ¨ Poorly crimped fittings – can’t see the hose through the

crimp; ferrule and hose are not fully engaged

¨ Issues with cam & groove fittings ¨ Improperly banded hose: if all of the buckles are in a line, that

may create a leak path and result in premature hose failure

¨ Other signs of significant deterioration such as blisters, soft or

bulging hose, cover gouging, wear and weathering/dry rot

¨ Compromised reinforcing wires ¨ Dents, twists or kinks ¨ Discoloration of color-coded hose cover ¨ Verify test date and that pressure is in conformity with

requirements for the application

ABOUT THE EDITOR:

¨ Check thread and seat connections

Debbie Mitchell Standards Manager at NAHAD - the Association for Hose and Accessories Distribution. NAHAD’s Hose Safety Institute© supports and promotes hose assembly safety, quality and reliability.

Internal Inspection: ¨ Loose hose tube (tube de-lamination) near the coupling ¨ Discolored hose tube due to chemical attack ¨ Cracks or flaking in the hose tube

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