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Types of Copper we buy and sell

Here are some photos of the types of copper we buy and sell Dry Bright Wire This type of copper be found inside insulated cable, It is ...

Monday 28 January 2019

We do not sell car parts or buy scrap cars, We recommed F W Cox Metals Ltd and London Auto Parts

We do not sell car parts or buy scrap cars, We recommend F W Cox Metals Ltd and London Auto Parts

F W Cox Metals ltd are based at Chesney Wold, Bleak 

Hall, Milton Keynes MK6 1LS · 01908 670669
and are a very good business if you are scrapping a car or
need car parts.

London Auto Parts are based at  19 Alperton Lane, Wembley HA0 1DX ·
020 8997 8787 and are also 
a very good business if you are scrapping a car 
or need car parts.

Sunday 27 January 2019

What is the difference between the magnetic properties of 304 and 316 stainless steel?

Magnetic and non-Magnetic Stainless Steel



There are several families of stainless steels with different physical properties. The magnetic properties of stainless steel are very dependent on the elements added into the alloy. A basic stainless steel has a ‘ferritic’ structure and is magnetic, formed from the addition of chromium – it can be hardened through the addition of carbon, making it ‘martensitic’. However, the most common stainless steels are ‘austenitic’ – these have a higher chromium content and nickel is also added. It is the nickel which modifies the physical structure of the steel and makes it theoretically non-magnetic.


304 stainless steel contains chromium (min. 18%), and nickel (min. 8%). It is an austenite steel and is only slightly responsive to magnetic fields. It also contains 18 – 20% chromium and 8-10.50% nickel, and lesser quantities of some other elements.

316 stainless steel is a molybdenum-alloyed steel. The fact that it is also negligibly responsive to magnetic fields means that it can be used in applications where a non-magnetic metal is required. It also contains a number of other elements in varying concentrations.

Type Analysis of Stainless Steel

Steel composition

Steel composition detail

Transformation from non-magnetic to magnetic phases

As both 316 and 304 stainless steels are austenitic, when they cool, the iron remains in the form of austenite (gamma iron), a phase of iron which is nonmagnetic. The different phases of solid iron correspond to different crystal structures. In other alloys of steel, this high-temperature phase of iron transforms to a magnetic phase when the metal cools. The presence of nickel in the stainless steel alloys stabilizes austenite against this phase transition as the alloy cools to room temperature. This corresponds to a somewhat larger magnetic susceptibility than we might expect for other nonmagnetic materials, but is still well below what might be considered magnetic.

However, this does not mean that you should expect to measure such a low susceptibility on any item of 304 or 316 stainless steel that you encounter. Any process which can change the crystal structure of stainless steel can cause austenite to be converted to the ferromagnetic martensite or ferrite forms of iron. These processes include cold working and welding. It is also possible for austenite to spontaneously convert to martensite at low temperatures. To complicate matters further, the magnetic properties of these alloys depend on the alloy composition. Within the allowed ranges of variation of Ni and Cr, significant differences in magnetic properties may be observed for a given alloy.

Practical implications for removal of stainless steel particles

Both 304 and 316 stainless steel possess paramagnetic characteristics.  As a result of these properties small particles (approx 0.1-3mm dia sphere for example) can be attracted to powerful magnetic separators positioned in the product stream. Depending upon their weight and specifically their weight ratio to magnetic attraction, these small particles will be held to the magnets during the production process.

These can then be removed during the magnet cleaning operation. From our experience 304SS small particles are more likely to be held in the flow than 316 SS particles due to its slightly more magnetic nature.

Tuesday 22 January 2019

Auto Scrap Metals and Values

This Post is for the attention of Car, Van or Lorry Repair workshop owners. 


If you are an owner of a car, van or lorry repair workshop then Scrap Metal would be something you see quite often, Scrap Metal auto parts build up so quick you would be more inclined to just give it away to a passing scrap collector to regain space to work.

Our advice would be to hang on to the most valuable items as you would see a steady monthly income flowing back into your motor repair business for just by selling these waste metal auto parts to scrap metal merchants like us.

Car Scrap items worth selling as follows

Car Batteries
Alternators
Brake Discs
Gear Boxes
Car Looms
Alloy Wheels
Catalytic converters
DPF's

Below is a list of items not worth hanging on to if you short of space.

Body panels
Exhaust systems
Break Pads
Clutches
Break Shoes


Reason being these items are only light iron which is the least valuable type of metal and you would need 5-10 times more in weight to generate the same amount of money compared to the items on the other list.

There is no collection charge for valuable auto scrap metals, we just weigh your items pay you the price which has been calculated by bank transfer then load it all up, it's as simple as that, once your bank details are on system it becomes even quicker as we just click a few buttons and your cleared funds will be in your bank in an instant.

Please note we do not take away car body shells and most scrap yards will still require a logbook to allow a delivery or collection of a scrap car body shell.  

Friday 4 January 2019

UPVC Window Recycling

We do not offer a Free UPVC Window Recycling 

service, As the nearest place we can take it to is Erith i

Kent, this would be too far for us to transport it, however if 

you have  large amounts of UPVC plastics you may find the 

details below useful.



Details of a company 

that specialise in recycling UPVC.


The company name is

RRS London Ltd 

Union Yard 

Manor Road 

Erith 

DA8 2AD 

01322336096 

07714308662

John


Hopefully in the future we will have more commercial plastic

recycling facilities, this will make plastics worthwhile 

collecting and profitable for small recycling businesses.