Monel Pipes & Tubes

The registered trademark name, Monel, is applied as the prefix name to several corrosion resistant alloys produced by Special Metals Corporation. These alloys are nickel-based and exhibit traits that include high resistance to atmospheric corrosion, salt water, and various acid and alkaline solutions.

Alloys of identical chemical and mechanical properties are available from other manufacturers and offer excellent alternatives to the various Monel® brand alloys.

The corrosion-resistant alloy is widely used in the marine, oil and chemical processing industries

 

Characteristics of Monel

  • Good resistance to acids such as hydrofluoric and sulfuric acid
  • Highly resistant to alkalis
  • Malleable
  • Highly corrosion resistant
  • Stronger than steel

Applications of Monel

  • Pump shafts, oil-well tools, instruments, doctor blades and scrapers, springs, valve trim, fasteners, marine propeller shafts
  • Marine components
  • Chemical and hydrocarbon processing equipment
  • Valves, pumps, shafts, fittings, heat exchangers

Monel Avalibility

We supply Monel400, K500, R-405. Most of these grades are available in the form of plate, sheet, pipe, tubing, fittings, bar, wire and rod.

 

Monel 400, Alloy 400, UNS N04400, 3074 / NA 13, 2.4360, NiCu 30 Fe

Monel 400 is a nickel-copper alloy (about 67% Ni – 23% Cu) that is resistant to sea water and steam at high temperatures as well as to salt and caustic solutions. Alloy 400 is a solid solution alloy that can only be hardened by cold working. This nickel alloy exhibits characteristics like good corrosion resistance, good weldability and high strength. A low corrosion rate in rapidly flowing brackish or seawater combined with excellent resistance to stress-corrosion cracking in most freshwaters, and its resistance to a variety of corrosive conditions led to its wide use in marine applications and other non-oxidizing chloride solutions. This nickel alloy is particularly resistant to hydrochloric and hydrofluoric acids when they are de-aerated. As would be expected from its high copper content, alloy 400 is rapidly attacked by nitric acid and ammonia systems.

Monel 400 has great mechanical properties at subzero temperatures, can be used in temperatures up to 1000° F, and its melting point is 2370-2460° F. However, alloy 400 is low in strength in the annealed condition so, a variety of tempers may be used to increase the strength.

 

Monel K500, Alloy K-500, UNS N05500, 3074 / NA 18, 2.4375, NiCu 30 Al

Monel K500 is a precipitation-hardenable nickel-copper alloy that combines the excellent corrosion resistance characteristic of Monel 400 with the added advantage of greater strength and hardness. These amplified properties, strength and hardness, are obtained by adding aluminum and titanium to the nickel-copper base and by a thermal processing used to effect precipitation, typically called age hardening or aging. When in the age-hardened condition, Monel K-500 has a greater tendency toward stress-corrosion cracking in some environments than Monel 400. Alloy K-500 has approximately three times the yield strength and double the tensile strength when compared with alloy 400. Plus, it can be further strengthened by cold working prior to precipitation hardening. The strength of this nickel steel alloy is maintained to 1200° F but stays ductile and tough down to temperatures of 400° F. Its melting range is 2400-2460° F.

This nickel alloy is spark resistant and non-magnetic to -200° F. However, it is possible to develop a magnetic layer on the surface of the material during processing. Aluminum and copper may be selectively oxidized during heating, leaving a magnetic nickel rich film on the outside. Pickling or Monel K-500 Barsbright dipping in acid can remove this magnetic film and restore the non-magnetic properties

 

 

Monel R-405, UNS N04405, 13Cr-Al, S40500, A268 TP405, 1.4002, SUS405(JISG3463)

Monel R405 is the free machining version of Monel 400. It is a nickel-copper alloy with a controlled amount of sulfur added to provide sulfide inclusions that act as chip breakers during machining. Like Monel 400, alloy R-405 is resistant to sea water and steam at high temperatures as well as to salt and caustic solutions. Monel R405 is a solid solution alloy that can only be hardened by cold working. This nickel alloy exhibits characteristics like good corrosion-resistance, good weldability and high strength. A low corrosion rate in rapidly flowing brackish or seawater combined with excellent resistance to stress corrosion cracking in most freshwaters, and its resistance to a variety of corrosive conditions led to its wide use in marine applications and other non-oxidizing chloride solutions. This nickel steel alloy is particularly resistant to hydrochloric and hydrofluoric acidswhenthey are de-aerated. As would be expected from its high copper content, alloy R-405 is rapidly attacked by nitric acid and ammonia systems.

As with alloy 400, Monel R-405 is virtually immune to chloride ion stress corrosion cracking in typical environments. Generally, its corrosion resistance is very good in reducing environments, but poor in oxidizing conditions. It is not useful in oxidizing acids, such as nitric acid and nitrous. Nevertheless, it is resistant to most alkalis, salts, waters, food products, organic substances and atmospheric conditions at normal and elevated temperatures.

Monel 400 and R-405 offer about the same corrosion resistance as nickel but with higher maximum working pressures and temperatures and at a lower cost due to its superior ability to be machined.