Automatic Recirculation Valves Installation

The DATIAN automatic recirculation valves are best installed directly on the outlet of the pumps for which they are meant. The valve layout is mainly based on the pump curve. Ensure that the valves are installed on the right pumps. The flow direction is indicated on the valve nameplate. This nameplate is riveted to the valve body. On this nameplate you will also find the valve’s commissioning- or fabrication number. This number is unique and therefore different for each valve. This ensures that the valves can always be related to the right pump. In case of spare parts requirements always refer to this number.

As a standard the valves are supplied as a complete unit and can be installed directly after receipt. Normally the connections are flanged but upon request we can also supply the valves with butt weld ends. The packing which are required between the valves and the piping are not part of our scope of supply. These packing can be supplied as an option. This is also the case with the bolts and nuts. Depending on the weight of the valves and the installation position the valves can be installed by hand or with the help of a tackle.

Before installing the valves one must make sure that the system is without pressure. The pumps must be switched off and the lines must be drained and clean. Isolating valves should be closed to prevent eventual backflow from other lines or tanks. The flange covers of the valves must be removed before installing. Make sure that no foreign materials drop into the valves after removal of the covers. If the valves are installed after a long storage time it is advised to check them on possible rust. Clean the valves if necessary.

Valve for vertical installation (main flow upwards) with flanged connections:

Lift the valve by hand or with a tackle on top of the pump outlet flange. Make sure that the right flange packing is correctly positioned between the valve inlet flange and the pump outlet flange.

The lifting strap shall be slung around the valve outlet flange. Do not use the bypass flange to lift the valve. The flange bolts should be tightened crosswise.

Now connect the flange of the main process line to the valve outlet.

Finally the bypass piping is connected to the valve bypass flange.

 (Note that the valve internals can be inspected/removed „inline“).

In case of horizontal installation it is most practical to use two straps, one around each main

flange, to position the valve in front of the pump outlet flange. Connect the valve to the pump and the piping as described above.

The valve bypass connection must be orientated in a horizontal or vertically down position to prevent the settlement of possible dirt on the moving parts of the valve. The valve bypass connection should not be installed in a vertical upwards position. The weight of the check valve would tend to pull it out of its seat.

It is not always easy to install the valve directly on the pump outlet. In those cases where the distance between pump outlet and valve inlet is less than 1.5 meter the valve inlet can be connected directly to the piping coming from the pump. If this distance is bigger the planned location must be indicated in case of order so that it is taken into account with the design (especially with low pressure systems the distance in vertical direction can influence the valve layout considerably). Valves ordered for horizontal installation should not be installed vertical ,and vice versa ,without consulting us.

Minimum straight pipe length after the valve: 10 x d (d= internal valve outlet diameter).

Minimum distance before reducing or enlarging the pipeline diameter : 4 x d.

For valves with welding connection, it is important to check the dimensions and material selection of all the connections before installing them. Check if the weld edges are without damage.

With the order for valves with welding connection, the following data must be available.

•Outside diameter of the connecting piping

•Inside diameter of the connecting piping

•Material of the connecting piping

•Weld edge preparation and directives for weld-grooves (figure number).

Based on the above data the valves are supplied with welded on connection pieces so that they can be welded directly into the pipeline. The bypass connection is always flanged. The welding work at site is no part of our scope of supply.

When hoisting valves with weld connection, special care is required because the hoist-straps cannot be hooked around a flange and an exact positioning is required for the welding work. For the rest the instructions are as with flanged valves.

Once the valves are installed the system can be pressurized to check on possible leakage.

The maximum test pressure is depending on the pressure rating of the valves and the valve material (ANSI or DIN standards). After the pressure test the valves are ready for start-up.

Automatic Recirculation Valve Installation And Maintenance

Before the valve is shipped all connections (flanges or weld connection.) are covered with plastic caps. This way the valve internals are protected against the ingress of dirt and damage. Before the valve is installed these covers must be removed. After a visual inspection on possible shipping damages and eventual presence of dirt/solids the valve can be installed in the direction of the arrow. The DATIAN series PSG are very maintenance friendly. The only maintenance required is the exchange of the soft-parts and the cleaning of the internals during the annual inspection and the exchange of springs every 3-5 years depending on the operating conditions. Other parts only have to be exchanged when they are damaged or when there are changes in process conditions.

Before inspection and assembly the complete valve must be cleaned, especially the contact- and guiding area’s of the valve internals. Soft parts must be exchanged with every inspection. Inspections that are part of a revision plan are customer responsibility.

Gate Valves

The gate valve is the most generally used valve in industry. Gate valves are well suitable for water, oil and gasoline services as well as a variety of other liquids. They are meant for on‐off flow control and should only be applied in the completely open or completely closed place. When completely opened, fluid through the valve is in a directly line, producing in minimum stress drop throughout the valve. China gate valve are bi‐directional and can be used for circulation in possibly way.
Ladish Valves gate product line are manufactured as full port, with threaded, socket‐weld, flanged and butt weld ends. Pressure classes include 150 through 1500. From our Houston, Texas manufacturing facility, we offer valves in the following materials: CF8M, CF3M, CF8, CF3, CK20, CG8M, CF8C, CN7M, CW12MW, CY40, CW6MC, N12MV, N7M, M35‐1, CZ100, CD3MN and many others.
DESIGN HIGHLIGHTS
Double Disc Available for Class 150
Round Bonnet Design Standard in Class 150, 3” thru 8”
Special Trims Available
Solid and Flexible Wedge Available ½” thru 2”
Flanged, Butt Weld, Threaded and Socket Weld End Connections Available
API 600 or API 603 Available
Valve Design per ASME B16.34

Datian Valve: Pressure Reducing Valve

Datian Valve: Pressure Reducing Valve: The Model 720 Pressure Reducing Valve is a hydraulically operated, diaphragm actuated control valve that reduces higher upstream pressure ...

Pressure Reducing Valve

The Model 720 Pressure Reducing Valve is a hydraulically operated, diaphragm actuated control valve that reduces higher upstream pressure to lower constant downstream pressure regardless of fluctuating demand or varying upstream pressure.
The Mode is a pilot controlled valve equipped with an adjustable, 2-Way pressure reducing pilot.
The needle valve  continuously allows flow from the valve inlet into the upper control chamber. The pilot senses downstream pressure. Should this pressure rise above pilot setting, the pilot throttles, enabling pressure in the upper control chamber to accumulate, causing the main valve to throttle closed, decreasing downstream pressure to pilot setting. Should downstream pressure fall below pilot setting, the pilot releases accumulated pressure, and the main valve modulates open. The integral orifice between the lower control chamber and valve outlet moderates valve reactions. The needle valve controls the closing speed. The downstream cock valve enables manual closing.
The Pressure Reducing Valve shall reduce higher upstream pressure to lower preset downstream pressure regardless of fluctuating demand or varying upstream pressure.
Main Valve: The main valve shall be a center guided, diaphragm actuated globe valve of either oblique (Y) or angle pattern design. The body shall have a replaceable, raised, stainless steel seat ring. The valve shall have an unobstructed flow path, with no stem guides, bearings, or supporting ribs. The body and cover shall be ductile iron. All external bolts, nuts, and studs shall be Duplex  coated. All valve components shall be accessible and serviceable without removing the valve from the pipeline.
Actuator: The actuator assembly shall be double chambered with an inherent separating partition between the lower surface of the diaphragm and the main valve. The entire actuator assembly (seal disk to top cover) shall be removable from the valve as an integral unit. The stainless steel valve shaft shall be center guided by a bearing in the separating partition. The replaceable radial seal disk shall include a resilient seal and shall be capable of accepting a V-Port Throttling Plug by bolting.
Control System: The control system shall consist of a 2-Way adjustable, direct acting, pressure reducing pilot valve, a needle valve, isolating cock valves, and a filter. All fittings shall be forged brass or stainless steel. The assembled valve shall be hydraulically tested and factory adjusted to customer requirements.
Quality Assurance: The valve manufacturer shall be certified according to the ISO 9001 Quality Assurance Standard. The main valve shall be certified as a complete drinking water valve according to NSF, WRAS, and other recognized standards.
Network design requires establishing various pressure zones due to topography, distances, demands, energy costs, reservoir availability, etc. The pump supplies water to the network and to the reservoir. System pressure is too high for the residential neighborhood, requiring a pressure reducing system.
By-Pass Pressure Reducing Valve saves on maintenance costs. The larger (more costly to maintain) valve operates during peak demand. The smaller by-pass valve cuts operating hours of the larger valve, achieving greater return on investment. For high differential pressure systems, see BERMAD publication 720-PD Proportional Pressure Reducing Valve. For high pressure systems, see BERMAD publication 820 Piston Actuated Pressure Reducing Valve.

Pump protection valve

Sealing apparent can alone await on average burden to seal, that is, depending on the average burden to columnist the sealing face of aboideau to the added ancillary of the valve bench to ensure the automatic pump recirculation valve apparent of the seal, this is the seal. Most is affected sealing aboideau valve, the valve is closed, to await on alfresco force affected the ram burden to the valve seat, to ensure the sealing apparent sealing.
Gate valve of the damper as a beeline band with the stem, alleged appropriation batten aboideau valve (also alleged ascent axis aboideau valves). Usually on the appropriation rod is trapezoidal thread, through the valve adviser canal on the top of the nut and the valve body, about-face the rotary motion into beeline motion, which is the operating torque beforehand into operation.
Open the valve When the aboideau hoisting acme is according to valve admeasurement 1:1 times, aqueous approach is unimpeded, but at runtime, the position cannot be monitored. When absolute use, the vertices on the valve axis as a sign, that is not moving, as it is in the abounding accessible position. To accede locking abnormality in a temperature change, usually in the drive to the acme position, cascade 1/2-1 ring back, afresh as a absolutely accessible the valve position. Slab aboideau valve in the absolutely accessible position, therefore, according to the area of the gate.
Some aboideau valve, the valve axis nut amid in ram, pump protection valve the handwheel circling to drive the stem, and accomplish the disc, the valve is alleged alternating batten aboideau or non-rising axis aboideau valves.
Manual valve alive principle: alternating the handwheel, through a duke caster and spiral cilia of the valve axis of the beforehand and retreat, appropriation or blurred the valve bowl affiliated to the valve stem, ability the role of accessible and closed.
Gate valve has the afterward advantages: baby aqueous resistance. Accessible and abutting a case. Average breeze administration is not restricted, abashed flow, abate the pressure. Simple form, the anatomy breadth is short, accomplish acceptable manufacturability, ambit of appliance is wide.Gate valve faults are as follows: simple could could could cause chafe and abrasion, apparent aliment added difficult. Needs assertive amplitude ambit is bigger, open,open and abutting time is long. Anatomy is almost complex.
Has continued been on the bazaar use a accepted accepted valve leaks or decayed phenomenon, application the European high-tech adaptable and valve accomplishment technology of adaptable bench allowance API 6A gate valve, overcomes the accepted aboideau allowance bad, defects such as rust, allowance aboideau valves of the adaptable abject bench accouter adjustable disc to aftermath adaptable anamorphosis advantage action to accomplish acceptable sealing effect, this valve has the about-face light, reliable sealing, acceptable adaptable anamnesis and continued account activity and added cogent advantages.
Can be broadly acclimated in tap water, sewage, construction, petroleum, chemical, food, medicine, ablaze textile, electric power, shipbuilding, metallurgy, activity systems, such as activity acclimated as acclimation and the cease device.
Seal aboideau valves of the adaptable abject bench of the features:
Made from ablaze weight: the aesthetics with chief asperous casting iron, compared with acceptable aboideau valves, the weight of about 20% ~ 20% abridgement in weight, simple accession and maintenance.
Flat anchor block: acceptable aboideau generally ablution the brawl valve in the baptize afterwards the alien altar such as stones, wood, cement, adamant filings, assorted sedimentation on the basal of the valve such as china control valve, simple to could could could cause cannot abutting deeply to anatomy a arising phenomenon, allowance aboideau valves application the aforementioned as the aqueduct at the basal of the adaptable abject bench of the collapsed design, not simple could could could cause bits deposition, to breeze unimpeded.

Safety Valve

The Pressure Safety Valve is a valve mechanism for the automatic release of a gas from a boiler, Pressure Vessel, or other system when the pressure or temperature exceeds preset limits. It is part of a bigger set named Pressure Safety Valves (PSV) or Pressure Relief Valves (PRV). The other parts of the set are named Relief Valves, safety relief valves, pilot-operated safety relief valves, low pressure safety valves, vacuum pressure safety valves.

Pressure Relief Valves were first used on steam boilers during the industrial revolution. Early boilers without them were prone to accidental Explosion.

Pressure safety Valves also evolved to protect equipment such as pressure vessel (fired or not) and heat exchangers. Safety valveterm should be limited to compressible fluid application (gas, vapor, steam).

The two general types of protection encountered in industry are thermal protection and flow protection. For liquid-packed vessels, thermal relief valves are generally characterized by the relatively small size of the safety valve necessary to provide protection from excess pressure caused by thermal expansion. In this case a small valve is adequate because most liquids are nearly incompressible, and so a relatively small amount of fluid discharged through the relief valve will produce a substantial reduction in pressure.

Flow protection is characterized by safety valves that are considerably larger than those mounted in thermal protection. They are generally sized for use in situations where significant quantities of gas or high volumes of liquid must be quickly discharged in order to protect the integrity of the vessel or pipeline. This protection can alternatively be achieved by installing a High Integrity Pressure Protection System (HIPPS)

We can offer a broad line of Safety Valves covering Relief Valve (RV), Safety Valve (SV), Safety Relief Valve (SRV), Pilot-operated Safety Relief Valve (POSRV), Low Pressure Safety Valve (LPSV), Vacuum Pressure Safety Valve (VPSV), Low and Vacuum Pressure Safety Valve (LVPSV).