Product - Ethylene Transfer Line and Docking Valves

​​​​​​​​Double Disc Technology – Double Block and Purge

​We are a world leader in Transfer Line Valves (TLV) & Decoking Valves (DV). IMI Z&J supplies high-quality Double Disc Through Conduit Gate valves which have higher safety levels than any other design. One double disc valve replaces two single gate valves - one plus one as backup installed in the same line to achieve the same safety Ievel.

Within the ethylene process heaters provide the cracking of hydro-carbons by means of hot steam. These heaters (steam crackers) suffer from a phenomenon where deposits of ‘coke’ accrue on the pipework and valves. From time to time these deposits must be removed (‘decoking’), ideally without shutting down the process completely. This is where our valves excel.



​Key features

  • True double block & purge performance within one valve body by means of two independent, separate shut-off discs (independent closure elements). Proven under ​critical/severe service conditions

  • Active, controlled and constant mechanical seating force when closed due to the central split-wedge-ball device

    • safe and reliable tight shut-off

  • Flat or round body valve design

  • Mounting options: flanges or welding ends

  • With reduced or full-bore passage

  • Long-lasting metal-to-metal seats, corrosion and wear resistant

  • Smooth tubular passage ln the open position (valve body free of solid particles)

  • Can be installed in any orientation

  • Designed to customer specifications and German or International standards

Benefits

  • Positive tight shut-off due to active & controlled mechanical sealing force when shut

  • Excellent performance, no risk of jamming due to internal split-wedge-ball arrangement

  • True Double Block & Purge within one valve body

  • Low wearing due to hardsurfaced seats

  • No build up of coke particles in the body due to guide plates and continuous steam purge

  • Suitable for media with extremely high solid-particle content

​​

  • Accommodates any desired type of actuator
  • Materials selected to suit operating conditions

  • Specially developed technique for crackfree hard-surfacing of the seats of ensures long-term maintenance-free service​









  • No jamming due to forces and moments resulting from the piping system

  • Force release of the discs prior to opening the valve (minimized wear)

  • Central sealing force due to ball-wedge mechanism

  • Seats continuously covered in the end position, thus preventing deposit build-up on the seat surfaces

  • 3 years maintenance free ​


Typical product specification - Double Disc Through Conduit

Temperatures
Up to 525 °C

Sizes
Up to 1400 mm

Materials
ASTM A 515 Grade 60/1.0425 acc.to EN (valve body) ASTMA387 Gr.12/1.7335 acc.to EN (throughway + discs) 1.4021/ similar to AISITP 420 (stem)

Features
Full bore (reduced bore on request)corrosion and wear-resistant hardfacing on seats, discs and throughway (stellite #6)outside screw-and-yoke type bolted cover valve with goggle plate​

Latest News

Valve Doctor programme celebrates 20th anniversary
16 September 2019
Unconventional support for the unconventional oil and gas industry
01 July 2019
INWED19
17 June 2019
IMI CCI showcases choke valve at DUG Rockies conference
04 June 2019
Jackie Hu appointed Divisional Managing Director of IMI Critical Engineering
07 March 2019
Roy Twite to succeed Mark Selway as Chief Executive of IMI plc
05 March 2019
IMI Critical holds Safety Summit
21 September 2018
New HSE handbook to help keep field service engineers safe
10 August 2018
Safety first at IMI Critical
31 July 2018
IMI InterAtiva’s Series RK Valves certified ‘fire-safe’
24 July 2018
IMI CCI participates at regional VPP Safety Summit
08 June 2018
Largest Romanian customer recommends IMI Remosa
10 May 2018
Lean success in IMI Critical back office functions
04 May 2018
Isolation valves adapted for Fluidised Catalytic Cracking applications
30 April 2018
IMI Critical Korea closes in on world-class LEAN performance
27 April 2018
IMI board tours IMI Critical businesses
25 April 2018
New positioner software tools from IMI STI
08 February 2018
Launch of Zero Backlash Scotch Yoke Mechanism
16 January 2018
IMI Critical Korea certified to sell actuators in Europe
20 September 2017
IMI Critical named ‘supplier of the year’ by Korea’s Doosan
19 September 2017
100th Valve Doctor graduates from IMI Critical
13 September 2017
Top HSE certification for IMI Critical’s California site
12 September 2017
Launch of High Endurance Actuator
21 April 2017
Launch of AB6350 valve
06 April 2017
Launch of 100DPC Multi-trim
17 March 2017
Launch of 840GS control valve
22 December 2016
IMI Critical to exhibit new technology at ADIPEC 2016
25 October 2016
New graduates join IMI Critical in four countries
22 September 2016
IMI Critical to take stand at ONS 2016 in Norway
16 August 2016
IMI Critical opens new China plant in Qingpu
27 July 2016
IMI CCI Korea celebrates 2,000 days of no “Lost Time Accident”
25 July 2016
Visit to IMI Z&J Germany by the Russian Economic Bureau from Bonn
11 July 2016
IMI Z&J Düren moves into modern offices
08 July 2016
IMI Critical Engineering forms strategic partnership with MRC Solberg & Andersen
05 April 2016
IMI Way Day 2016 date announced
01 March 2016
NEW IMI Eye – fourth edition
26 February 2016
IMI Critical co-locates China businesses
20 January 2016
IMI CCI Switzerland gains certification for new generation safety valves
18 December 2015
IMI Critical rise to Dragon challenge
30 November 2015
IMI STI achieves CRCC approval for new products
24 November 2015
IMI Truflo Marine Attend the Engineering Technology and Innovation Exhibition 2015
23 November 2015
IMI CCI Sweden secures new contracts on three continents
23 November 2015
IMI Critical Engineering appoints new petrochemicals head
05 November 2015
IMI CCI Czech Republic gains ‘Safe Enterprise’ certification
03 November 2015
IMI Critical announces 90mRMB investment in China
29 October 2015
IMI CCI SriCity wins regional safety award
27 October 2015
Key clients attend grand opening of new Aberdeen facility
23 October 2015
IMI companies ‘act as one’ to deliver for customer
02 October 2015
IMI CCI Sri City approved by NTPC
01 October 2015
IMI Critical Engineering showcases innovation at Valve World Expo Asia
28 September 2015
Nexen awards IMI Orton
25 September 2015
IMI Critical Engineering celebrates opening of new Jubail repair centre
23 September 2015
IMI Critical and IMI Precision join forces at Valve World Expo + Conference Asia 2015
21 September 2015
IMI Critical Engineering opening of new Jubail Repair Centre
18 September 2015
IMI CCI India manufactures first 1050MW turbine bypass valve
20 May 2015
Largest ever contract for IMI Critical Engineering
18 February 2015
New Houston facility opens
12 February 2015
IMI Critical completes acquisition of Bopp + Reuther
02 January 2015
IMI Critical takes family of brands to Valve World 2014
11 December 2014
IMI STI doubles size of Italian plant
20 October 2014

Contacts

​IMI Z&J Germany

IMI Z&J Houston (USA)

IMI Z&J Shanghai (China)

IMI Z&J South Africa
Product - Ethylene Transfer Line and Docking Valves