July 6, 2016 By Waverley Brownall

Corrosion Resistant Alloys In The Marine Industry

Corrosion resistant alloys are used extensively within the marine industry.

Applications where seawater is present requires tough alloys that are able to withstand corrosive surroundings.

Corrosion Resistant Alloys

Seawater can have devastating effects on metals such as iron where the surface of the metal will be attacked relentlessly. However, certain high-performance metals will give longevity and durability if they hold a number of certain properties.

Inconel and Monel are two special metals that perform highly within the marine industry. This section will cover the advantages of using these materials within fittings and valves in an aqueous environment.

Monel 400 Alloy

The nickel-based alloy MONEL 400 offers high strength and of course, corrosion resistance. It is an excellent choice for applications where seawater will be attacking the metal fitting, tube or valve.

Inconel 625

INCONEL 625 offers high resistance against pitting and crevice corrosion. Its high tensile strength makes it the perfect alloy for items such as propeller blades. Inconel 625 ranks within Class I of alloys that are most resistant to the marine environment.

625 has good corrosion fatigue strength when seawater is present. Poorer performances will be seen from alloys such as k-500 or x-750, however, this is in regard to evidence of pitting within stagnant seawater.*

* Versatile Corrosion Resistance of INCONEL alloy 625 in Various Aqueous and Chemical Processing Environments, Presented by Inco Alloys International Inc.

Titanium

Titanium is another metal that holds corrosion resistance properties. It can resist the effects of corrosion within fresh water or steam in temperatures up to 316°C. The temperature of resistance for seawater sits at 260°C. Deposits from marine environments may form, but pitting and crevice corrosion will be completely absent from the alloy itself.

Titanium is considered to be one of the best metals for seawater elements, it is perfect for splash zones and ASTM Grade 2 is essentially immune to seawater stress corrosion cracking. *Offered as a material for fittings and valves by Waverley Brownall.

This hardy material is known for its expense, but alloys with such strong resistances are an investment for the long-term health of structures such as offshore platforms as fatigue will not be an issue with the presence of seawater.

We offer material choices such as Hastelloy C276 and Incoloy 825.

In flowing and stagnant seawater conditions, Hastelloy C276 and Inconel 625 materials give excellent corrosion resistance. Inconel 825 can be susceptible to bio-fueling.

Corrosion Prevention

Corrosion resistant alloys do not need the consistent maintenance or treatments that other metals may require. Titanium or other metals that work well within the marine industry are investments that will secure health, safety and efficiency of the application in question for years to come.

It is cost-effective for companies in the long term, considering maintenance costs and installation replacements are virtually non-existent within a much longer time frame.

Some fittings manufacturers will charge for a full replacement of tube and fitting after 5 years – with alloys such as Titanium, this will be prolonged substantially.

Titanium alloys are known to be difficult-to-machine materials, which causes an even higher price-tag for fittings and valves. However – Waverley Brownall have been machining titanium alloys for over 40 years with specialist knowledge.

We are happy to take orders for titanium fittings for companies who are willing to invest in this incredible solution.

Types Of Corrosion Within A Marine Environment

Galvanic corrosion
Intergranular corrosion
Stress corrosion cracking
Crevice corrosionm
Erosion corrosion
Marine growth

Seawater environments can be divided into three main zones.

Zone 1) The first zone covers alloys that are fully immersed or continuously submerged.

Zone 2) Partially immersed such as tidal environments and splash zones .

Zone 3) Zone 3 covers corrosion that is predominantly due to the surrounding environment. As an example, this covers atmospheric and subsoil factors.

Zone 1, Submerged – The main elements that will impact the level of corrosion are temperature, oxygen levels, bio-fueling and pollution. For example, with our standard stainless steel products, pitting and crevice corrosion are the most common concerns for 316 in Zone 1.

For Zone 2 (partially submerged) for areas such as the splash zone, stainless steel has a much higher pitting corrosion rate due to oxygen exposure.

Alloy Selection For The Marine Industry

Do you require more information on the selection of special metals for a range of industries?

We are offering our readers a FREE GUIDE to assist you!

A Guide In The Selection Of Special Metals

FREE GUIDE
Posted for free directly to your address
Presented by Waverley Brownall Limited

Your A5 sized handbook will be posted to the address that
you fill out and submit in the form.

Your guide will include:

Corrosion by acids
Corrosion by alkali and salts
Aqueous corrosion resistance chart
Material composition chart
The benefits and properties of each metal we offer

June 30, 2016 By Waverley Brownall

Titanium Pipe Fittings UK | High Quality Titanium Alloy

Titanium was first discovered in 1791 by William Gregor, a Reverend in England who had a keen interest in minerals. Several years later it was also re-discovered in the ore Rutile by a German chemist called Martin Heinrich Klaproth. (He also discovered Uranium, Zirconium and Cerium.)

The pure form of the elemental metal titanium was not made until 1910.

The metal was formed by Matthew A. Hunter, a metallurgist and inventor from Auckland, New Zealand.

Origin of name: Titanium is reference to “Titans”, the sons of the Earth Goddess in Greek mythology.

Titanium Pipe Fittings, Tube Fittings and Valves

Titanium is known for its strength and surprisingly lightweight properties. It is used in the Oil and Gas industry, Aerospace industry and even used as the main alloy for medical implants .

Titanium Pipe Fittings

Waverley Brownall manufacture both low and high pressure pipe fittings in Titanium. We have specialised in the use of high performance alloy fittings manufacturing for over 40 years.

From our headquarters in the UK, we distribute our Oil & Gas fittings and valves across the world. With customers in South Africa, Italy and the United Arab Emirates.

Our pipe fittings are known for their consistent quality and remarkable durability.

SEND AN ENQUIRY

Titanium Tube Fittings And Valves

We manufacture single and twin ferrule compression fittings. These fittings have been supplied to some of the biggest companies the Oil and Gas industry. Contact us for information on product sizing, material and features. An engineer will be more than happy to answer any questions you may have.

To enquire about our tube fittings and valves in titanium, email: enquiries@waverleybrownall.co.uk

Titanium: A True Super Alloy

From being used as raw material in 3D printing methods, to supplying the International Space Station with strong titanium piping – titanium is a true super alloy.

Titanium is an alloy well suited to many industry applications. The categories include; Chemical processing, Marine and Offshore, LNG, Mining, Solar Power, Geothermal, Petrochemical and Pharmaceutical.

*For guidance on titanium’s corrosion resistance, temperatures and acidic concentrations please contact Waverley Brownall.

Waverley Brownall hold stock of raw titanium and finished fittings and valves. We can manufacture to order, with deliveries aiming to be no more than 6 weeks for the majority of our instrumentation.

enquiries@waverleybrownall.co.uk

The Aqueous Corrosion Resistance Of Titanium

Titanium resists all forms of corrosion from fresh or seawater to temperatures up to 260C.
Titanium tubing and instrumentation products have provided trouble-free seawater services for many industries
Titanium scored excellent on our Aqueous Resistance chart for Seawater and Chlorine (wet).

Upon exposure to air, the titanium alloy forms a passive oxide coating which protects the metal from further oxidation

More information can be seen on our special metals page.

SEND AN ENQUIRY

Here at Waverley Brownall, we hold a moderate amount of stock of Titanium raw material and finished products.

Our engineers can help you with technical questions, ordering and advise you on the use of titanium for large or small projects.

May 20, 2016 By Waverley Brownall

Super Duplex Pipe Fittings, Duplex Stainless Steel Fittings

Waverley Brownall’s Duplex stainless steel pipe fittings contain a mix of beneficial properties from Ferritic and Austentic steels.

Within the Duplex alloy, is high Chromium and Molybdenum content. It is this unique mix of characteristics that makes Duplex steel a great choice for coping against localised corrosion.

Our pipe fittings come in a range of sizes, with features and benefits for many different piping applications. Duplex stainless steel is roughly twice the strength of regular steel grades.

SEND AN ENQUIRY

Developed more than 70 years ago, Super Duplex still proves to be a great choice of material for pipe fittings.

Super Duplex Pipe Fittings: SD Stainless Steel Properties

Austenitic-Ferritic Iron Chromium, Nickel alloy with an addition of Molybdenum. The Super Duplex alloy has good resistance to pitting and stress corrosion cracking.

Compared to conventional stainless steels, super duplex has a high tensile strength which makes it suitable for the onshore and offshore industries.

Super Duplex can provide a solution for companies within the oil and gas sector, particularly the petrochemical industry because its high resistance to acids.

Applications of Super Duplex Stainless Steel & Duplex Stainless Steel

Other applications include: shipbuilding, heat exchangers, marine construction, pulp and paper, blast walls on offshore platforms and pipe systems in chemical tankers.

Duplex Stress corrosion cracking (SCC)

Stress corrosion cracking, also known as SCC is a form of alloy corrosion.

The causes and effects of this type of corrosion can differ regarding:

The tensile strength of the material
The temperature the material is exposed to
The corrosive nature of the surrounding environment

Standard Austenitic steel such as 304 are susceptible to stress corrosion cracking. Duplex stainless steel is an alloy that is suitable for higher temperature applications such as brewing tanks or desalination plants.

Questions? Email us

Characteristics of Duplex Stainless Steel Pipe Fittings

A higher strength compared to austentic and ferritic stainless steels
A range of corrosion resistance material properties
High quality Duplex and Super Duplex from Waverley Brownall ready for made-to-order fittings and valves
Safe for a vast number of applications across different industries
Super duplex is by definition a duplex stainless steel with a Pitting Resistance Equivalent Number (PREN) > 40, where PREN = %Cr + 3.3x(%Mo + 0.5x%W) + 16x%N

Super Duplex and Duplex Stainless Steel Pipe Fittings

Our pipe fittings as standard are supplied in a high quality 316 Stainless Steel.

However, with Super Duplex or Duplex Stainless Steels – you will receive all the benefits of this materials properties and extensive application choice.

SEND AN ENQUIRY

Our pipe fittings and related products include: High pressure hose adaptors, elbows and tees.

Also available are hose connectors, unions, plugs, bushes, seals and caps!