What is the difference between valve and valve

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Shut-off valves play a reg­u­la­to­ry and anti-emer­gency role in the oper­a­tion of the pipeline sys­tem. Its main ele­ments — a valve and a valve have a dif­fer­ence in design, prin­ci­ple of oper­a­tion, with the same oper­a­tional require­ments for them. Know­ing these dif­fer­ences will allow you to install an ele­ment that will ensure the great­est effi­cien­cy of the net­work.

Shut-off valves

What is meant by valve

The valve is a shut-off ele­ment of the pipeline, which can not only block the flow of the work­ing sub­stance, but also reg­u­late it. Its design allows you to set an adjustable flow: from max­i­mum to its com­plete ces­sa­tion with a num­ber of aver­age val­ues.

Design features in

Main details:

  • Frame. Most often cast, but there are mod­els with col­lapsi­ble parts. It has two holes through which liq­uid, gas pass­es. A lock­ing mech­a­nism is installed inside. For mount­ing in a pipeline sys­tem, it has two threads or holes for flange mount­ing. The valve will be through if these fas­ten­ing pipes are locat­ed on oppo­site sides. The cat­e­go­ry of angu­lar includes a valve with mutu­al­ly per­pen­dic­u­lar axes.
  • Lock­ing device. Con­sti­pa­tion — a valve sys­tem with a spin­dle, which are thread­ed to the guides. The valve in the form of a shut­ter is nee­dle-shaped and pop­pet-shaped.
  • Fly­wheel. This is a valve han­dle brought out to the out­side, cre­at­ing a load on the thread. Turn­ing the han­dle low­ers and rais­es the valve.

Seals for high-qual­i­ty over­lap are used in some types. When the valve is opened, the plate comes off the seat.

Types of valves

How to install

The fit­ting is installed so that the flow of the work­ing medi­um is bent at a right angle twice in two par­al­lel planes. In this case, liq­uid or gas flows under the plate, which cre­ates pres­sure on it in the “closed” mode of oper­a­tion from the side of the seat. This pres­sure some­what helps to sep­a­rate the plate from the seat when the valve is opened.

Note! If the direc­tion of flow is reversed, then when it opens, its pres­sure will cre­ate an addi­tion­al load on the valve and may rip off the stem.

Types of valve shut-off device

Accord­ing to the type of con­sti­pa­tion, valves are clas­si­fied into

  • Valve (valve crane). It has two par­ti­tions divid­ing the body into two parts. The par­ti­tion can be made in the form of a cone. The valve, as part of the stem, abuts against an elas­tic gas­ket in con­tact with the seat. Turn­ing the thread­ed con­nec­tion rais­es and low­ers the valve. This type of valve is designed for high pres­sure flow, easy to oper­ate, its shut-off device can be eas­i­ly replaced in the event of a break­down. The dis­ad­van­tage is the rapid wear of the rub­ber gas­ket.
  • Ball or valve. The lock­ing device is made in the form of a ball with a through slot. The size of the slot is deter­mined by the required flow of the work­ing medi­um. To com­plete­ly block the flow, the ball is moved so that its slot is ori­ent­ed per­pen­dic­u­lar to the flow. Such a valve los­es its reg­u­lat­ing func­tion.

What is meant by a valve

A gate valve is a shut-off ele­ment of the pipeline, in which the gate moves per­pen­dic­u­lar to the axis of the flow of the work­ing medi­um. It has the abil­i­ty to only com­plete­ly block the flow with­out the reg­u­la­tion func­tion. The block­ing ele­ment of the valves moves up — “open”, down — “closed”.

Types of gate valves

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Design features of gate valves

Main details:

  • Frame. Made by cast­ing.
  • Lock­ing mech­a­nism. It has the shape of a wedge that hides at the top of the sad­dle in the closed posi­tion.
  • Fly­wheel. It has a thread­ed han­dle con­nect­ed to a wedge.

When the fly­wheel is turned, the wedge goes down, enters the low­er part of the seat sur­face with rub­ber seals and blocks the through hole. Due to the con­stant fric­tion of the wedge against the seal, the lat­ter quick­ly becomes unus­able.

Impor­tant! The gate valve can be installed regard­less of the direc­tion of flow in the pipe, due to the per­pen­dic­u­lar ori­en­ta­tion of the lock­ing mech­a­nism and the com­plete absence of mix­ture move­ment resis­tance.

Sec­tion­al valve

Mate­r­i­al for the man­u­fac­ture of valves

There are valves and gate valves for instal­la­tion in pipelines in inter­nal (shel­tered) and exter­nal areas. Com­mon are con­sti­pa­tion made of brass, bronze, steel, includ­ing stain­less steel, cast iron. Recent­ly, plas­tic valves have become wide­spread. When choos­ing a shut-off valve, the fol­low­ing fac­tors are guid­ed:

  • The most reli­able, durable, func­tion­al devices are made from brass and bronze. They are suit­able for any type of work­ing mix­ture. Valves made of these mate­ri­als have proven them­selves well in heat­ing sys­tems: due to the absence of scale, there is no heat loss. The main dis­ad­van­tage is the high cost, which does not allow their use for large diam­e­ter pipes;
  • Exter­nal sec­tions of pipelines, large-diam­e­ter pipes are equipped with shut-off valves made of cast iron and steel. These mate­ri­als are strong enough to with­stand the high load pres­sure in the line, but at the same time they are much cheap­er than ana­logues made of bronze, brass;
  • The most com­mon and opti­mal option in terms of “price-qual­i­ty” for inter­nal water, gas, heat­ing sys­tems is stain­less steel. Due to their per­for­mance char­ac­ter­is­tics, stain­less steel valves are suit­able for instal­la­tion in all inter­nal pipeline net­works, even at high pres­sure. But it is not rec­om­mend­ed to block pipes with hot mix­tures with such con­sti­pa­tion. Scale builds up inside the device over time, which caus­es a decrease in flu­id flow;
  • Bud­get option — plas­tic valves. It is not rec­om­mend­ed for use in indus­tri­al high­ways, in exter­nal sec­tions of indi­vid­ual gas and water sup­ply sys­tems. Suit­able for inte­ri­or spaces. It is installed only on plas­tic pipes.
brass fit­ting

Gen­er­al signs of valves

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Valves and gate valves are designed to stop the flow of the work­ing mix­ture in pipelines for var­i­ous pur­pos­es. They can be thread­ed or flange mount­ed. For pipelines with a pres­sure of 1.6 MPa, a thread­ed con­nec­tion is con­sid­ered func­tion­al and durable. Indus­tri­al engi­neer­ing sys­tems with a work­ing pres­sure of more than 10 MPa from cast-iron (steel) ele­ments are blocked by shut-off valves installed on flanges. Plas­tic valves are weld­ed by spe­cial weld­ing.

The price is formed from the cost of the mate­r­i­al, design fea­tures, addi­tion­al parts used.

Char­ac­ter­is­tic dif­fer­ences

In gen­er­al, there are four main dif­fer­ences:

  • The valve has addi­tion­al func­tion­al­i­ty in the form of reg­u­la­tion of the flow of liq­uid, gas. The valve serves only to shut off the pipe;
  • Gate valves are more often used for large-diam­e­ter, high-pres­sure pipes, where, due to one-way pres­sure, the valve is very tight­ly adja­cent to the seat. Valves in such con­di­tions close the pipeline faster and eas­i­er, but open­ing is dif­fi­cult. With a strong hydraulic shock, the lock­ing mech­a­nism may become unus­able;
  • Valves fail faster as inter­nal seat O‑rings wear out;
  • Block­ing the sup­ply of liq­uid, gas in the valve occurs in a par­al­lel plane, and in the valve — in a per­pen­dic­u­lar one;
  • Valves are more expen­sive.
Main pipeline sec­tion

All types of valves serve have their own char­ac­ter­is­tics. Know­ing how the valve dif­fers from the valve in the design, the option is select­ed that will ensure the smooth oper­a­tion of the sys­tem.

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