January 2014 Tube Products International
41
products & developments
Aluminium precision tube made in China
Cold drawn seamlesss tube
Cold drawn coil tube
For
Seawater desalination device
Power generation heat exchanger
Industrial refrigerant system
WUXI HATAL ALUMINIUM CO., LTD
No. 72, Zhouxin (E) Road, Binhu District,
Wuxi, Jiangsu Province, 214121, China
Tel: +86 510 85069506
Fax: +86 510 85061423
E-mail:
Aluminium
tube in China
Quick-fit isolation valve
receives WRAS approval
NLB Engineering’s Aladdin EasyFit
Isolator, a quick-fit plumbing isolation
valve for 15mm pressurised pipe, has
received approval from WRAS for use
as a stop valve with a maximum working
pressure of 16 bar.
Company director John Heffernan
commented, “A major UK water
company requested we seek WRAS
stop-cock approval for the Aladdin
EasyFit Isolator. They already use
them every week to fit in-house water
meters, and they will now be used
for many other routine jobs where the
Aladdin EasyFit Isolator will become the
standard replacement stopcock on the
mains supply.”
The Aladdin EasyFit Isolator installs
into pressurised hot or cold pipe-work
when the mains stopcock is seized or
inaccessible. It avoids draining down
and re-filling of heating
systems, and can
isolate mains ware feeds
in
multi-occupancy
buildings.
It can also be used as an emergency
shut-off for leaking pipes.
A video is available on the product’s
website (
),
showing how quick and straightforward
the valve is to fit.
NLB Engineering Ltd
– UK
NLB Engineering’s
Aladdin EasyFit
Isolator valve
Weld seam detection on precision
steel tubes
The position of a weld seam has a
crucial influence on the quality of the
final product when bending or hydraulic
forming a tube. An unfavourable seam
position causes deviations in geometry,
has influence on the firmness and in the
life span of the produced component
or precipitates by cracking during the
manufacturing process.
In order to prevent such disadvantages,
different solutions for the localisation
of the weld seam were established.
Common optical procedures, such as
colour marking of the longitudinal welds,
in order to detect their position are
widespread. Camera-based systems
that detect the visible welding seam are
also in use.
However, colour marking is not always
possible, or the welding seam may not
be visible. This problem arises when
an application requires a treatment of
the tube after welding, for example
in the production of precision steel
tubes. The cold drawing of the tubes
changes the original surface and
impedes the use of colour. If the tube is
additionally annealed, the welding seam
may become invisible in its external
appearance.
Roland Electronic offers alternative
techniques, well known from the non-
destructive testing of materials with
eddy current, magnetic induction and
the magnetic leakage flux method.
These techniques have the advantage
of dry functioning, without significant
radiation exposure.
Crystalline modifications of the structure
within the weld seam can be used for
detection. In the process of welding
ferromagnetic steel, martensitic crystals
are formed within the range of the heat
effect zone. Since martensitic crystals
hardly occur in the unwelded structure,
the welding seam is detected by the
crystal structure modification. The
SND40 weld seam detector supports
these alternative techniques and offers
high process reliability in practical
usage.
Roland Electronic claims that tubes
with scraped weld seam and calibrated
diameter will reach in the first detection
run ratios of 99.9 per cent, and that the
error rates in detection with an SND40
system are between 0 and 100 ppm.
Roland Electronic GmbH
– Germany
