If you work with process piping, you've likely come across small ring-shaped spool pieces tucked between a set of flanges — often near an orifice plate or flow meter. These are bleed rings, also known as flushing rings, and while they're small, they play a big role in keeping industrial piping systems safe, efficient, and easy to maintain.

At Hydro Blind Solutions, we manufacture bleed rings and flushing rings to exacting industry standards. Here's what they are, how they work, and why they matter.

What Is a Bleed Ring / Flushing Ring?

A bleed ring is a thin, ring-shaped spacer installed between a pair of pipe flanges — most commonly at an orifice plate, flow meter, or other in-line instrument. Around its outer edge, the ring has small tapped ports that give operators direct access to the interior of the pipe without having to break the flanged connection.

These ports allow crews to:

• Bleed or vent trapped gas or pressure from the line
• Drain liquid out of a pipe section
• Flush the line with a cleaning or purging fluid
• Connect instrumentation, such as differential pressure transmitters used for flow measurement

Where Are Bleed Rings Used?

Bleed rings are most commonly found in orifice flange assemblies, sandwiched between the orifice plate and the flanges (or between the flanges and the pipe itself). They're a staple in oil & gas, chemical processing, power generation, and other industrial piping systems where operators need to isolate, drain, or flush a line section without shutting down the entire process.

Why Use a Bleed Ring?

Without a bleed ring, draining or venting a section of pipe would mean disassembling the entire flanged joint — a slower, more labor-intensive, and potentially hazardous process, especially with pressurized or hazardous fluids. With a bleed ring in place, operators simply open a small valve on the ring itself. It's faster, safer, and minimizes disruption to the system.

Hydro Blind Solutions: Bleed Ring & Flushing Ring Specifications

Our bleed rings and flushing rings are built to perform under the same demanding conditions as the flanges they're installed alongside.

Pressure and Temperature Rating Bleed rings and flushing rings are designed to withstand any pressure–temperature combination that an ASME flange will withstand.

Tap Sizes

• 1/2" or 3/4" threaded or socket-weld taps are standard.
• Multiple taps can be provided but must be oriented by the customer.
• Ring thickness may be affected if larger taps are required.

Coating One coat of standard shop primer is applied to all carbon steel rings unless otherwise specified.

Standard Materials

• SA516 Gr. 70
• 304 Stainless Steel
• 316 Stainless Steel
• Other alloys can be furnished upon request.

Codes of Practice Bleed rings and flushing rings are produced in strict accordance with:

• ASME B16.5
• ASME B16.20
• ASME B16.47 (for larger diameter flanges)

Additional Notes

• Standard finish: 125–250 AARH serrated finish
• Higher ASME pressure ratings available
• Larger sizes available
• Hydro Blind Solutions reserves the right to modify dimensions, materials, or design. Consult our factory for certification details.

Talk to Hydro Blind Solutions

Whether you need a standard bleed ring for an orifice flange assembly or a custom-engineered flushing ring for a demanding application, Hydro Blind Solutions has the materials, tap configurations, and certifications to match your project's requirements. Contact our team today to discuss specifications and get a quote.