Process valve with butt weld ends

It’s absolute­ly tight, durable and ver­sa­tile – for iso­la­tion and con­trol even in harsh indus­tri­al envi­ron­ments. Ari-Armaturen’s metal­lic seal­ing, triple off­set Zetrix process valve is a pre­mi­um prod­uct for the inter­na­tion­al mar­ket that out­lasts and out­per­forms the com­pe­ti­tion. New: A ver­sion with butt weld ends is now also avail­able from Ari as an alter­na­tive to the dou­ble flanged and ful­ly lugged designs.

Zetrix unites all the ben­e­fits of a metal­lic seal­ing process valve with the advan­tages of a but­ter­fly design. With its small foot­print and reduced weight, this cut­ting-edge but­ter­fly valve is very easy to han­dle. The triple off­set prin­ci­ple guar­an­tees a per­ma­nent­ly tight seal con­form­ing to leak­age rate A as per DIN EN 12266–1, because the valve fits pre­cise­ly and clos­es with­out fric­tion. Avail­able in cast or stain­less steel, it can option­al­ly be used as an iso­la­tion and con­trol valve – yet anoth­er exam­ple of its great versatility.

Zetrix is suit­able for liq­uids, gas­es and vapours in a wide range of appli­ca­tions, for exam­ple in oil and gas pro­cess­ing, refiner­ies, petro­chem­i­cals, chem­i­cals, solar ther­mal pow­er sta­tions, pow­er plants, dis­trict heat­ing, pulp and paper, steel­works, sug­ar pro­cess­ing and indus­tri­al and plant man­u­fac­tur­ing in general.

The Zetrix design was devel­oped and opti­mised using the very lat­est gen­er­a­tion of tools, includ­ing the finite ele­ment method, con­tact angle cal­cu­la­tions, flow sim­u­la­tions and char­ac­ter­is­tic mea­sure­ments. Field tests (e.g. fire safe) and endurance tri­als were car­ried out at an accred­it­ed test­ing lab­o­ra­to­ry as well as in our own exper­i­men­tal lab. The new Zetrix process valve has been test­ed and approved as fire safe accord­ing to ISO 15848 / Ger­man clean air reg­u­la­tions (TA-Luft) and SIL.

The finite ele­ment method (FEM) is a numer­i­cal cal­cu­la­tion tech­nique that was used to sim­u­late the stress­es and their dis­tri­b­u­tion occur­ring over the valve disc. The aim was to achieve the required strength at pres­sure load lev­els in com­bi­na­tion with a slim and flow friend­ly shape.

The media flow through the pip­ing sys­tem was addi­tion­al­ly deter­mined with the help of flow sim­u­la­tions which enabled the flow veloc­i­ty, flow direc­tion and pres­sure dis­tri­b­u­tion to be visualised.
Due to the opti­mised disc geom­e­try, tur­bu­lences have been min­imised and pres­sure loss pre­vent­ed. The result: uni­form flow plus a high flow capacity.

The flow val­ues in dif­fer­ent valve posi­tions were mea­sured on a spe­cial test sec­tion in our in-house lab­o­ra­to­ry. The curves obtained in this way were used to fine-tune the con­trol char­ac­ter­is­tic of the process valve.

The rota­tion of the lamel­lar seal­ing ring into the body seat was opti­mised by ensur­ing that all seal­ing geom­e­try para­me­ters are pre­cise­ly coor­di­nat­ed. The ide­al plug shape that is crit­i­cal for fric­tion­less open­ing and clos­ing of the Zetrix valve was then computed.

Last but not least, the new valve was sub­ject­ed to the acid test. In many appli­ca­tions there is an increased fire haz­ard. In the event of a fire, the valve must con­tin­ue to meet inter­nal and exter­nal leak-tight­ness require­ments for a defined peri­od of time if exposed to direct flame impinge­ment. This abil­i­ty was impres­sive­ly demon­strat­ed in a fire safe test accord­ing to ISO 10497 / API 607 6th Edition.

Key fea­tures at a glance
The metal­lic seal­ing Zetrix has a triple off­set design; in addi­tion to a “smart”, self-align­ing seal­ing ring, it also pro­vides iso­lat­ing and con­trol func­tions. It is tight clos­ing accord­ing to DIN EN 12266 (leak­age rate A), has a stel­lit­ed seat, hard­ened shaft bear­ings and a blow-out proof stem as stan­dard and can be used as a pipe-end valve on both sides. The valve can be insu­lat­ed in line with indus­tri­al stan­dards and has ISO 15848 / TA-Luft, ISO 10497 / API 607 6th Edi­tion fire safe and SIL approvals.

The Zetrix design com­plies with DIN, ANSI and API spec­i­fi­ca­tions, and the valve can be made from either cast car­bon steel (1.0619 +N; SA216WCB) or stain­less steel (1.4408; SA351CF8M). Its face-to-face length cor­re­sponds to DIN EN 558–1 Series 13 (dou­ble flanged), Series 16 (ful­ly lugged) or Series 14 (new ver­sion with butt weld ends). The valve is rat­ed for oper­a­tion at tem­per­a­tures from ‑29°C to +427°C.

Zetrix process valves are avail­able in sev­er­al dif­fer­ent nom­i­nal diam­e­ters from DN 80 to DN 1200, for nom­i­nal pres­sures from PN 10 to PN 40 and con­form­ing to Class 150 or Class 300, depend­ing on the type of con­nec­tion. Apart from the dou­ble flanged design, the valves can also be ordered as a ful­ly lugged ver­sion or – in future – with butt weld ends. Zetrix valves are used with a man­u­al gear­box or with a pneu­mat­ic, elec­tric or hydraulic actu­a­tor. The man­u­fac­tur­er empha­sis­es that oth­er con­fig­u­ra­tions, e.g. cus­tomer-spec­i­fied con­nec­tion types, nom­i­nal diam­e­ters, pres­sure class­es, face-to-face lengths, mate­ri­als and tem­per­a­ture ranges can also be imple­ment­ed on request.

The above-men­tioned prod­uct series is fur­ther enhanced with an array of use­ful options: a flush­ing port for the shaft bear­ings and a buffer port for pro­tect­ing the stuff­ing box, a flush­ing port for the bot­tom flange, a weld­ed bot­tom flange, a dou­ble pack­ing with a drainage line (e.g. for ther­mal oil ser­vices), a test port, a “clean air” bush­ing accord­ing to TA-Luft, a sol­id seal­ing ring for spe­cial appli­ca­tions, a heat­ing jack­et for high vis­cos­i­ty flu­ids and blow-out pro­tec­tion to API 609.

Zetrix is typ­i­cal­ly used in the oil and gas indus­try, chem­i­cals and petro­chem­i­cals, dis­trict heat­ing, ener­gy and pow­er plants, iron and steel, food and bev­er­ages, sug­ar mak­ing, ship­build­ing, the gas sec­tor and pulp and paper.