Gosco M-Class Block & Bleed Valves

Block & Bleed Valve Overview

Gosco M-Class Block & Bleed Valves are not only fully bi-directional, they seal bubble tight with full differential pressures or a 1psi pressure drop. Features include: High pressure options, (Up to Class 4500), NACE compatibility, live-loaded metal seats, our proprietary boronizing process, arcuate cut balls, exotic alloys, and integral body options. We can fully customize them with varying end caps, different size trim sets, and flexible face to face dimensions.


The Gosco M-Class Block & Bleed Valves are essentially two bi-directional valves with a bleed valve between them. This means we meet all definitions of API 6D for double block & bleed (DBB), double isolation & bleed (DIB), and OSHA double block & bleed (DBB). Not only that, our valves seal bubble tight in both directions with a 1 psi drop, or full differential. We offer valves in pressures up to Class 4500, in exotic alloys, and we are NACE approved.

Bi-Directional Sealing

Each of the two ball/seat assemblies in the Gosco M-Class Block & Bleed Valves have 
bi-directional sealing abilities. This means that regardless of which direction the valve is installed in the pipeline, the high pressure from either end can’t reach the bleed port, and high pressure from the bleed port can’t reach either end. Gosco M-Class Block & Bleed Valves provide true double isolation, since both ball/seat assemblies can seal in either direction and at any pressure differential.

Superior Trim Hardening

BORONIZING is a thermo-chemical surface hardening process that creates a surface layer that’s so hard, it can’t be measured on the Rockwell C Scale. We use Inconel 718 because it is the best overall metal for corrosion, high temperature, and wear resistance. Our PROPRIETARY BORONIZING has a layer depth over 100 microns (0.004”) and a hardness between HV 2500-2700. 

Compared to HVOF coatings, BORONIZING is: 
Substantially harder, markedly more wear resistant, impervious to corrosion, and is capable of handling huge temperature shocks without spalling or flaking.

Seat/Spring Design

Gosco’s patented seat/spring design is perfect for powder/catalyst applications. When powder gets trapped in the spring cavity, it causes the valve to “lock up”. To solve this issue, Gosco uses a completely different approach to the competition – instead of trying to seal the spring from the media, we deliberately open up the cavity around the spring. This allows the media to flow around the spring, but also allows it to escape just as easily. Media never gets trapped in the valve, so we never have issues with valves “locking up”.

Tripod Mounting System

The M-Class Tripod Mount allows you to install the valve in any orientation without supporting the actuator, and we use Finite Element Analysis (FEA) to guarantee it. The very unique design also eliminates actuator misalignment. Three evenly-spaced prongs define a plane, preventing the actuator from rocking. When paired with a CNC machined mounting plate that cannot move left to right or back and forth, the actuator is guaranteed to be aligned correctly. Additionally, the packing can be adjusted without having to remove the actuator, and the three tripod prongs act as a heat sink to minimize the amount of heat that gets to the actuator.

Exotic Alloys

If you can cast it, or it is available in bar stock/forgings, Gosco can create your own bespoke M-Class 3-Way Diverter Valve, even with metals that require vacuum casting (e.g. titanium). We are not restricted to making merely the body from exotic alloys, as we can manufacture all components to your exact specifications, right down to the bolting. Our engineering team at Gosco Valves has extensive experience in corrosive applications, and we can recommend the best material to use for your specific application.

Made To Order

Not all processes are the same, and applications exist where standard valves just don’t cut it. Our strength is being able to find solutions to problems that other manufacturers simply don’t have the capability to solve. Gosco has a team of specialized engineers, an independent R&D facility, cutting edge design technology and decades of experience in severe service applications. We also have a “Think Outside the Box” philosophy, and a “Say Yes” attitude, so when you need a BESPOKE valve, made exactly to your specifications – you have come to the right company.

  • Block & Bleed Sizes

    NPS ½ FP to NPS 16 SP
    ½″ FP to 16″ SP

  • Block & Bleed Connections

    150# to 4500#, NPT, SW,
    BW, Graylock and Custom

  • Block & Bleed Applications

    Customizable with bubble tight 
    sealing, exotic alloys & metal seats.

  • Block & Bleed Temperatures

    -100°C to 675°C 
    -148°F to 1247°F


Gosco M-Class Catalogue Printable

Gosco M-Class Catalogue Printable

Gosco M-Class IOM Manual

Gosco M-Class IOM Manual

Gosco M-Class Valve Catalogues Overview

Gosco M-Class Valve Catalogues Overview

Gosco M-Class Valve Presentations

Gosco M-Class Valve Presentations


Talk to one of our Experts

Reach out to our team of Spraying, Pumping, Filtering, Valve, and Systems Specialists today. We know we can help you with any municipal or industrial application challenges.