Tank Blanketing Valves

The Mark 518 is a back-pressure regulator for use in low pressure air and gas services. With a selection of six pressure ranges, set points can be chosen to control back-pressures from 1" w.c. to 7 psi (3mbar to 0,5 bar). As a standard feature, the MK518 is provided with soft seals for ANSI Class VI shutoff. The valve is also leak-proof under vacuum conditions.

The Mark 518 back-pressure relief valve is used for maintaining the pressure of air and gases in the positive inches w.c. (mbar) pressure range.

Features & Benefits
  • Completely self-operated – Spring-loaded regulator operates off of process pressure and requires no external power source or air supply for operation
  • Wide range of low back-pressure settings – Choose from six pressure ranges for set points ranging from 1” w.c. to 7 psi (3mbar to 0,5 bar)
  • Long service life – All metal wetted parts produced from stainless steel or Hastelloy C for durability and long life
  • Tight shutoff – Soft seats for ANSI Class VI shutoff

Sizes: 1″, 2″, 4″ (DN25, DN50, DN100)

End Connections: ANSI (150), DIN (PN16), NPT (1″/DN25 size only)

Body: 316 Stainless Steel
Trim: 316 Stainless Steel or Hastelloy C
Spring Housing: Steel
Diaphragm: PTFE or Viton
Valve Seat: J-6000 Black (with PTFE diaphragm) or Viton (with Viton diaphragm)

Service: low pressure air or gas

Shutoff: ANSI Class VI


Tank Blanketing Reference Guide

Need a quick reference guide showing the quick specs of our most popular tank blanketing valves? We have you covered! Download our Reference Guide.

What Is Tank Blanketing?

Learn the basics about tank blanketing. Read on!

What is Tank Blanketing (Part 2)

Learn more about tank blanketing.


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