Liquid Flow Rate

When liquid is poured from a pail, glugging, splashing and slow flow are common complaints. A smooth, controlled pour will increase user safety when dispensing chemicals, minimize valuable product loss and eliminate the need for clean-up labour. APC’s anti-glug (AG) closures and APC-6 plug vent were designed to dampen liquid pulsing and increase product flow. Our Pail Closure Flow Rates graph shows the performance you can expect from APC closures.

Option #1

(blue line on Flow Rates chart)

Pail closures such as the APC-25 and APC-7(without controls) can exhibit glugging or pulsing as liquid exits the pail through the small diameter of the closure neck. This occurs because:

• Lower air pressure builds inside the pail due to the liquid outflow
• Higher air pressure outside the pail pushes against the liquid outflow, until air enters the pail in a large pulse

Option #2

(green line on Flow Rates chart)

APC anti-glug closures (APC-25-AG, APC-25-AG-MV and APC-7-AG) smooth liquid flow by restricting liquid outflow and allowing steady air inflow through the spout neck as follows:

• AG tabs fold in to limit the liquid outflow to about 90% of the closure neck diameter
• Air inflows continuously above the liquid outflow and forms bubbles beside the pail cover
• Air bubbles float up through the liquid at a speed that depends on the liquid viscosity
• Bubbles rise most quickly in liquids with a viscosity close to water (e.g., janitorial chemicals) making AG closures the most effective choice for these products

Option #3

(red line on Flow Rates chart)

APC-6 plug vents are mounted on the pail cover opposite the main closure (APC-25 or APC-7). The separate air vent is opened to equalize air pressure inside the pail and ensure a smooth, fast flow.

• Plug vent introduces air above the liquid level which increases liquid outflow
• APC-6 vents are effective for liquids with higher viscosities (e.g., petroleum lubricants) making plug vents the most effective choice for these products

Quality Management

Since APC began production in 1997, we have had a track record of manufacturing high quality pail closures. Our products are manufactured and inspected under a detailed quality management system to ensure that all closures conform to our high standards:

• Our contract molder Revere Plastics Systems is registered under quality management system ISO 9001:2015
• Our experienced operators, inspectors and state of the art assembly machines minimize non-conformances
• We use only FDA approved virgin resins made in the USA. Resin Product Stewardship Bulletins are available upon request

UN Performance Rating

APC-25 and APC-7 closures may be qualified by testing for use on UN rated open-head plastic pails:

• Suitable for UN packing groups II and III
• Recommended max specific gravity is 1.5
• Recommended maximum hydrostatic pressure rating is 30 kPa (4.5 psi)