Marine parts, components resistant to salt water & air | Global Sources
by Cecile de Veyra (Managing Editor)
Image source: Shutterstock
Studies show that salty environments corrode metal faster than freshwater and usual humidity – up to five times more quickly with salt water and 10 times with salty air, according to sciencing.com. Microbes also pose a danger to metal as there are iron-eating bacteria in oceans, such as those found in the wreck of the Titanic. While this phenomenon can be considered nature’s way of disposing of sunken ships, oil rigs and metal debris, it is also a reason to seek out better materials and protective coating solutions for boats, oil platforms, undersea tunnels and offshore pipelines currently being used.
In parts and components used in all types of sea vessels, there are various materials available, depending on the application. They are marine-grade or can withstand not just water and saltwater corrosion but are also sturdy enough for strong winds and rough seas.
AH36, DH36 or EH36 carbon steel and MD, ME, MF and MG alloy steel are used in structural shipbuilding and other offshore structural applications, according to US-based Metal Supermarkets, the world's largest provider of small-quantity metals. In aluminum, 5052, 5083 and 6061-T6 grades are marine-rated for the same uses as well as docks, and boat hulls and lifts. Stainless steel in 316 and 304 grades are options for marine fittings, fasteners and structures, with galvanized steel also suitable for offshore engineering facilities. Copper-nickel alloys, such as C70600 and C71500 types, are alternatives to stainless steel and also recommended for water lines, desalination equipment, valves and pumps. For propellers, propeller shafts, pipes and marine fasteners, silicon, aluminum and phosphor bronze alloys are commonly used. Marine or naval brass, specifically alloys C46200, C46400, C48200 and C48500, are materials for pipes, marine fittings and fasteners, and pumps.
For long wear, keeping metal parts in good condition, especially on a recreational boat, contributes to both appearance and overall resale value. In addition to rinsing and drying, online resource and guide Discover Boating recommends waxes, varnishes and polymer protectants. For hulls, engines and other metals onboard, keeping them immersed completely in oil, antifreeze or kerosene will help minimize corrosion, according to sciencing.com.
The NMM-RK1-016 from Qingdao Nancy Metal & Machinery Co. Ltd is a JIS F7302-standard angle valve with a body and a bonnet made of tin bronze and a disc or seat of aluminum bronze. It can handle up to 5kgf/sqm. Sizes range from DN15 to DN65. MOQ is 10 pieces and lead time 10 to 30 days.
Made of 316 stainless steel, this part from Liyang Hengyu Machining Co. Ltd is for marine instruments and processed using machining, milling and drilling. An order of at least 100 pieces is required. Lead time is 22 to 25 days.
A marine or mooring bollard, Chonghong Industries Ltd’s model CHD01287 is made of 316 or 304 grade stainless steel with a high mirror polish. It is available in 120x95x120mm and 150x120x150mm versions, weighing 916g and 1.512kg respectively. The supplier requires a minimum order of 10 pieces.
For an order of at least 100 pieces, Dongying Tousin Precision Metal Co. Ltd can ship the Marine Hardware001 in 35 to 45 days. This product is silica soy cast from stainless, carbon or alloy steel.
Linyi Jiate Import & Export Co. Ltd markets the 1220*2440*3-21mm-5070 marine plywood with a poplar, hardwood or mixed wood/combi core, and okoume or pencil cedar face and back. WBP glue is used. This 1,220x2,440mm board is available in BB/BB and BB/CC grades and 4 to 20mm thicknesses. MOQ is 500 pieces and lead time seven to 10 days.
Dalian Ruici Industry Co. Ltd’s RC1046 is a sand-cast or CNC-machined marine propeller made of manganese bronze or Cu1, Mn-Fe bronze or Cu2, Ni-Al bronze or Cu3 or Mn-Al bronze or Cu4. Stainless steel can also be used. A minimum order of 50 pieces is required. Lead time is 45 to 60 days.
