Q Are the BS EN European standards the same as the old British standards?
A Most are similar but there are detailed differences. Check the standards or Publication 120.
|
Q What are DGS and NES standards?
A Naval engineering standards are prepared for material for the UK Ministry of Defence. They replace Directorate General ships standards.
|
Q A copper is specified on a drawing as C110. What is this and is there a UK equivalent?
A This refers to the ASTM (American) specification C11000. The UK equivalent is C101 - an electrolytic tough pitch conductivity copper.
|
Q A drawing for a bearing specifies CuSn10Pb10. What is this?
A A leaded bronze consisting of 10% tin, 10% lead, the balance being copper. designated LB2 or is BS EN CC495K.
|
Q A Specification describes a brass as CDA 360. What is this?
A This is an old CDA Inc (USA) spec. It is now ASTM 36000. The UK equivalent is CZ 124 (BS EN CW603N). It is a free machining brass.
|
Q How much silver is present in nickel silvers?
A None, nickel silvers are copper-nickel-zinc alloys which have an attractive colour when polished.
|
Q A drawing specifies TUNGUM for a pipe. What is TUNGUM?
A TUNGUM is a trade name for aluminium-nickel-silicon brass. CZ127(CW 700R).
|
Q A drawing refers to a material as B16. What is this?
A B16 is an ASTM specification for free cutting brass rod and bar.
|
Q Is there a difference in properties between continuous cast versus centrifugally cast aluminium bronze?
A Yes, in the EN specification the properties are quoted separately for continuous cast (GC) and centrifugally cast (GZ) conditions.
|
Q I have been asked by a customer if the leaded brass CZ121Pb3 (CW614N) that I am using to make leaded inserts is RoHS compliant. What does this mean?
A The RoHS Directive stands for "the restriction of the use of certain hazardous substances in electrical and electronic equipment". This directive bans the placing on the EU market of new electrical and electronic equipment containing more than agreed levels of lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyl (PBB) and polybrominated diphenyl ether (PBDE) flame retardants. The allowed limit for lead in copper alloys is 4%; CW614N has a lead range from 2.5 to 3.5% so it is compliant.
|
Q A company wishes to replace a worn sealing segment in a steam turbine. The segment operates at 600oC, its function being to stop steam escaping. The segments are machined from bar. The current material is from an old spec. and consists of Cu 65, Ni13, Sn2, Pb5 Zn14 Fe0.9 Which alloy could I specify?
A The alloy used looks like a special brass and fits no current standard. The 600oC is a high working temperature for copper alloys and the nearest available alloy is a leaded nickel silver (NS101, CW402J) which has an annealing temperature between 600 and 700oC.
|
Q Is Naval Brass CZ112 (1-1.4% tin) still available?
A No, the nearest alloy to Naval Brass is a leaded brass CW712R, available in rod, bar and wire. For sheet and plate the UNS Alloy C46400 (0.5 to 1.0% tin ) is used.
|
Q Is wrought fire refined copper (C104) available?
A No, C104 is regarded as low grade due to impurities. All copper is refined (purified) by electrolysis.
|
Q I am trying to identify the brass Hpb59-1. It is proposed to use this brass in the cast condition for valves used in fire protection systems in buildings.
A This is a Chinese Specification composition 57-60 copper, 0.8-1.9% lead, balance zinc. It is a leaded Muntz Metal. A more suitable alloy for this application would be the gunmetal LG2 (CC491K) 85%copper, 5% tin, 5% zinc, 5% lead. It has better corrosion resistance and is easily cast.
|
Q Can you help me with an old brass specification BS S 369: 1940?
A BS S 369:1963 5 per cent phosphor bronze (copper-tin-phosphorus) rods and sections (other than forging stock) withdrawn and replaced by:
BS 2874:1969 Specification for copper and copper alloys. Rods and sections (other than forging stock) withdrawn because requirements were included in:
BS 2874:1986 Specification for copper and copper alloy rods and sections (other than forging stock) withdrawn and replaced by:
BS EN 12163:1998 Copper and copper alloys.
Rod for general purposes and
BS EN 12164:1998 Copper and copper alloys. Rod for free machining purposes and
BS EN 12167:1998 Copper and copper alloys. Profiles and rectangular bar for general purposes
The standards in bold are current.
|
Q Could you please identify an old brass specification BSB11?
A This is an Aerospace spec. "Brass bars suitable for brazing or silver soldering 1917. It was withdrawn and replaced by BS2B11 1930 which became BS3B 1933 which was withdrawn in 1990 and not replaced. The most appropriate spec. to consult is BS EN 1044:1999 "Specifcation for filler metals for brazing."
|
