Bursting Disc (Rupture Disc)? Or Safety Relief valve? – Why not Both??

Bursting Disc (Rupture Disc) VS Safety Relief valve VS Both

Often thought of in an isolated way, bursting discs and the safety pressure relief valve are generally specified to protect applications as an “or” solution.  A bursting disc “on its own” is generally a more reliable solution than the PRV “on it’s own” because of the following

  • Discs are leak tight
  • They can be operated much closer to the set pressure
  • There are no moving parts – virtually maintenance free
  • They do not require re-setting
  • They open more quickly in an emergency situation – allowing maximum flow
  • They cannot stick
  • They do not block or “Gum up”
  • They are corrosion resistant – The media remains in the system

But why not exploits the strength of both technologies?

A safety pressure relief valve combined with a bursting disc has become common practice especially in the pharmaceutical, chemical, oil and gas  plants for the following reasons:

In addition, some of the benefits of using safety relief valve combined with bursting disc are:

  • When in use, the rupture disc provides a superior process seal, therefore reducing fugitive emissions
  • Valves re-close after an over-pressure event, thus saving process media and allowing operation to continue until the bursting  disc can be replaced
  • The combination allows for a less expensive valve material and additionally extends the valve’s life and requires less maintenance as the valve is not exposed so frequently to the media
  • Potentially has an impact  overall costs, both short and long-term
Pressure Relief Valve Bursting Disc PRV + Bursting Disc
Leak Tight High Yes Yes
Cost High - must be shut down to be checked periodically Low Medium
Maintenance High - must be shut down to be checked periodically Low Medium
Adjustable Yes No- fixed setting Yes
Reclosable Yes No Yes
Reusable Yes No - must be replaced after each use Valve is reusable, disc is not

Assentech supplyinstall and service full range of storage tank and fluid transfer equipment in the UK and Europe.

At Assentech, we supply a broad range of services to the fluid process, transfer and storage industries. We provide technical assistance, installation and maintenance for all of the products we offer, as well as for similar equipment from 3rd party manufacturers. We work closely with manufacturers and end users to ensure that the services we offer are fit for purpose and proportionate to our customers’ needs. Our engineers are fully insured to work on COMAH sites and provide Risk Assessments and Method Statements in advance as standard.

After conducting a Third Party Witness Inspection, I was most impressed with Ewart and his team, their professionalism, and product knowledge I found to be excellent.

Ian Johnston

Director, RAK Inspection

Emergency-Relief-Valve-Pilot-Operated-2500a  Assentech- Geodesic Dome Installation

Assentech were subcontracted to assemble and install a 25m geodesic dome for Shaft G on the Lee Tunnel project. My experience with Assentech from pre-contract through to assembly has been very positive. Unlike other subcontractors I have experienced on this project, Assentech had a very positive attitude to producing the level of documentation required for a project of this scale. Leading to a high quality pre construction packaged approved in a timely manner. The communication regarding the manufacturing process was first class allowing us to easily plan our works and prepare the site. Dome assembly was carried out very efficiently and completed to programme. The task was correctly resourced and well supervised. The work force had a positive attitude and carried out the task safely. In summary from my perspective it has been a very easy subcontract to manage with a high quality finished product.

Robert Colthorpe

Site Agent – Lee Tunnel Project, Morgan Sindall

Emergency-Relief-Valve-Pilot-Operated-2500a  Assentech wins supplier excellence award from Eastman Chemicals

We were extremely pleased with the level of service and professionalism demonstrated by Assentech, right from our initial enquiry, through delivery and post installation. As a recipient of only two of these awards made by Eastman Chemical Company in the UK, based on performance in 2014, Assentech are rightly proud of their achievements.

Robert Dodgson

TH3 Project Procurement Lead, Eastman Chemical Company

Emergency-Relief-Valve-Pilot-Operated-2500a  AssentechIFR Installations at Vopak, Teesside

As you said “you delivered what it said on the tin”. On time and on budget.  Your up front engineering to determine the suitability of your product for our application was second to none, i have not seen anyone else in the industry pay as much attention to detail before you get the purchase order number as Assentech.

Garry Lee

Project Manager, Vopak Limited

Emergency-Relief-Valve-Pilot-Operated-2500a  AssentechIFR Installations at Vopak, Teesside

Assentech have supported our Navigator Terminal (formerly known as Vopak Teesside) on two important ~
projects by providing technical assistance and supplying and fitting a total of 11 Internal floating roofs. Both projects have been completed on schedule and on budget. Assentech have provided an excellent level of experience and front end engineering support with high quality drawings and documentation. Their specialist on site labour have worked collaboratively with us and Assentech have proven to be open, honest and flexible partners.
We have experience of both their Heavy Duty Pontoon type and Full Contact IFR’s and we continually monitor operation and performance of all lFR units Installed on site and consider the Assentech supplied Matrix brand to be the best in the market with exceptional build quality and rigidity. Our clients have inspected the installations and have always remarked upon the build quality and have been impressed with their strength in fully supporting up to four people without noticeable deformation. The design and construction of their stainless steel shoe seals continue to prove to operate excellently with no noticeable reduction in performance or flotation ability over the time since Installation.
Assentsch have proven to be extremely competitive on price and their installation and inspection activities have always been thorough. Navigator therefore have no hesitation in recommending Assentech to other companies considering their services.

Brian Beddow

Project Manager, Navigator Terminals Seal Sands