Sample bottles from 50cc to 2000cc are available ex stock.

Materials available include standard glass bottles, high temperature glass bottles, amber glass bottles, polyethylene bottles, polypropylene bottles, plastic coated glass bottles and stainless steel bottles.

Bottles include caps for use with septum and double caps.  Septa are availaible in a variety of materials to suit the process including; natural rubber, EPDM, Teflon coated butyl rubber, Teflon coated Silicone and Viton.

Contact Derwent James for datasheets and prices info@derwentjames.co.uk

Additional product information and product pictures have been added to our website for Dopak, Badotherm and Presreg.  Please take a look and let us know what you think.

info@derwentjames.co.uk

Parameters that determine the design of a remote seal

• Location of the transmitter (indoor versus outdoor)
• Temperatures (process and ambient)
• Exposure to vacuum
• Pressure (operating and maximum)
• Length of capillary
• Type of seal desired
• Process connection, material of construction and similar considerations.
• Installation requirements
• Measurement span.

Ways to reduce measurement errors

• Seals with a large measuring diaphragm provide better results.
• The amount of error attributable to significant changes in either the process or ambient temperature varies widely with the combination of seal, capillary and fills fluid.
• Keep capillary lengths as short as possible.
• Never mount seals and capillaries in direct sunlight.
• Use capillaries of the same length on both taps when measuring differential pressure.
• Keep diaphragm sizes equal to both sides
• Be sure that both capillaries experience the same temperature. For instance, avoid installing one capillary in a shady area and the other in the sun. This eliminates zero shifts that results from unequal thermal expansion and contraction of the fill fluid in the high and low legs.
• The most common application of diaphragm seals is for level measurement. Proper ranging of a transmitter for level service requires considering the specific gravity of both the fill fluid and the process fluid.
• With dual-leg pressure transmitters, mismatched fill volumes (unequal lengths of capillary), degree of mismatch between seals (same sizes tend to offset any unbalance, though not completely) or uneven temperatures on seals and capillaries can affect the readings.
• Be careful with operators installing the application; for example, can easily cause a failure of a diaphragm seal simply by unscrewing the capillary.
• Another source of error is temperature effects. Although fill fluids are typically designed to minimize thermal expansion as much as possible, all fluids tend to expand as the temperature rises, increasing the pressure in the capillary and introducing an error.
• The volume of fill fluid should be minimized by using a capillary with a small bore and careful profiling of the seat behind the diaphragm.
• The specific gravity (SG) of the fill fluid itself can also introduce an error if the capillary extends vertically. This is a common problem in applications such as liquid level measurement
• It is important that the measuring range of the transmitter is sufficiently wide to allow the system to be zeroed to take any changes in level into account. Temperature variations will also have an effect here, because they change the density of the fill fluid.
• With GP / AP (gauge pressure and absolute pressure) transmitters mount diaphragm seals direct to the transmitter, if possible.
• With DP and AP, be sure that the lowest pressure (vacuum) at the transmitter side is always within the specification of the transmitter.

For more information on Badotherm diaphragm seals email us at info@derwentjames.co.uk

Diaphragm seals are used throughout the chemical and petrochemical industry to separate a pressure instrument from the process.  This protection enhances the lifetime of the measuring instrument significantly. However it can happen that the diaphragm eventually breaks. One of the advantages of diaphragm seals is that THEY CAN BE RENEWED, whilst RE-USING the pressure instrument. It will function just as a new instrument, but with the benefits of LOWER COST and a much SHORTER LEADTIME than buying a new instrument with seals.

Badotherm has been supplying this service for over 25 YEARS to its customers.

All brands of transmitters with diaphragm seals can be sent back to Badotherm because they operate independently of all transmitter manufacturers.

Urgent repairs can also be accomodated WITHIN 48 HOURS! in which they will provide a full assessment of the pressure instrument to improve its reliability and lifetime.

So if you have an urgent, difficult or unreliable pressure instrument then contact us today and we will ensure a SPEEDY COLLECTION of your pressure instrument with seals so a full assessment can be carried out by the Badotherm experts.

CONTACT DERWENT JAMES TODAY FOR MORE DETAILS 01332 673700

In addition to our extensive experience in the specification of manual sampling systems for hazardous liquids and gases Derwent James Ltd can now call upon our expert colleagues at Badotherm Instrumentation and Presreg Valves to solve your Instrumentation applications.

For high quality pressure gauges or high quality pressure regulators contact us for further details, a product datasheet or a quotation.

info@derwentjames.co.uk

As the exclusive UK agent for Dopak sampling systems Derwent James Ltd are best placed to advise you on best practice when it comes to the safe sampling of hazardous liquids and gases.

Dopak sampling systems are installed worldwide so Dopak have the experience and knowledge when designing systems to enable a plant operator to take an emission free sample of liquids (into bottles) and gases or liquefied gases (into cylinders).

Contact Derwent James today for more details on Dopak sampling systems.

info@derwentjames.co.uk

Derwent James Ltd are pleased to announce that they will be exhibiting at the Tank Storage Association conference and exhibition on 22nd September 2011 in Coventry, UK.

This is the UK’s leading event for the bulk liquid storage sector for those who work in the fuels, chemicals, potable liquids, edible oils and fats storage industries and brings together people who care about safe and effective bulk liquid storage operations.

The conference presenters, drawn from the Health & Safety Executive, the Environment Agency and industry address a diverse range of critical issues facing the industry.

We will be exhibiting Dopak sampling systems and Presreg Valves.

For more information on the Tank Storage Association please visit http://www.tankstorage.org.uk/conference-exhibition/

Badotherm obtained ATEX approval for their full range of pressure gauges some years ago and until recently these ATEX approved gauges have been manufactured to order.

However due to an increase in demand for Badotherm ATEX certified pressure gauges they are now available from stock in both BDT18 process style and BDT20 safety pattern style.

Please note that Badotherm now also have ATEX approval for dial thermometers which are currently manufactured to order.

For more details please contact info@derwentjames.co.uk

From time to time we will recommend other suppliers of equipment which we feel might be of interest to you.  The first recommendation is UK based Total Lockout (safety) Ltd.

Total Lockout (Safety) Ltd offer a complete range of products and services for lockout tagout safety systems. They can help you with product selection and ensure that your safety padlocks are protected against key duplication.

 http://www.totallockout.com/valve-lockouts

The standard Dopak DPM sampler in system purge configuration ensures the retrieval of a representative and contamination free sample.

This system is now available in a NEW configuration with a flexible dip tube and submerged pump. This new arrangement allows for sampling of liquids from the top of large vessels (with or without agitator) where insufficient vacuum can be created to lift the liquid from the vessel.

So, if you need to take contained liquid samples from tanks/vessels with insufficient vacuum source available then please request details of the Dopak DPM sampler c/w dip pipe & submerged pump.

info@derwentjames.co.uk