1. Overview of self-operated differential pressure regulating valve:
ZYF-16 self-operated differential pressure control valve does not require external energy, and relies on the pressure change of the medium to be regulated for automatic adjustment, automatically eliminates the remaining pressure head of the pipe network and the flow change caused by pressure fluctuations, and keeps the user's inlet and outlet pressure differences constant. Helps stabilize system operation. Especially suitable for household metering or automatic control system.
2. Performance characteristics of self-operated differential pressure regulating valve:
The differential pressure valve is a double disc structure with small unbalanced force of the valve stem and compact structure. It is used in the heating (air conditioning) water system to keep the pressure difference of the controlled system constant, and has the following characteristics:
1. Constant pressure difference of the controlled system;
2. Support the internal self-regulation of the controlled system;
3. Absorb the pressure difference fluctuation of the external network;
4. The advanced stepless pressure regulation structure is adopted, and the control pressure difference can be adjusted up to 25:1;
5. It has the function of automatically eliminating blockage;
6. The flange size conforms to GB4216.2 medium gray cast iron flange size.

The drainage pumps used in buildings include submersible sewage pumps, submerged sewage pumps, vertical sewage pumps and horizontal sewage pumps. Due to the generally small site in the building and the small displacement, submersible sewage pumps and submerged sewage pumps can be preferred for drainage pumps. Among them, submerged sewage pumps are generally used in important places; vertical sewage pumps and horizontal sewage pumps require isolation. Seismic foundation, self-irrigating water absorption, and occupying a certain amount of space, so it is rarely used in buildings.

The flow rate of fire pumps and sewage pumps should be selected according to the second flow rate of domestic drainage design; when there is displacement adjustment, it can be selected according to the maximum hourly flow rate of domestic drainage. The flow rate of the drainage pump in the fire elevator sump is not less than 10L/s. The head of the sewage pump is calculated and determined according to the lifting height and pipeline loss, and then a certain free head is added. The free water head should be 0.02~0.03MPa. The flow velocity of the sewage pump suction pipe and outlet pipe should not be less than 0.7m/s, and should not be greater than 2.0m/s.

In public buildings, a spare pump should be set up for each domestic drainage sump, and it should be operated alternately at ordinary times. For the drainage of the basement, equipment room, and garage to flush the ground, if there are two or more drainage pumps, there is no need to install a pump. When the sump cannot be equipped with an emergency drainage pipe, the water pump should have uninterrupted power supply; when the drainage inlet pipe can be closed, the uninterrupted power supply may not be provided, but an alarm device should be provided.

When lifting sewage and wastewater with large impurities, the outlet pipes of submersible sewage pumps in different sumps should not be discharged together; when lifting general waste water, the outlet pipes of submersible sewage pumps in different sumps can be combined and discharged according to the actual situation .

When two or more water pumps share one outlet pipe, valves and check valves should be installed on the outlet pipe of each pump. When the drainage of a single water pump may cause backflow, a check valve should be installed. It is not allowed to combine the pressure drain and the gravity drain in the building. When the submersible sewage pump lifts large debris, the submersible sewage pump should be equipped with a crushing device; when lifting sewage containing more fibers, a large channel submersible sewage pump should be used.

When the motor power of the submersible sewage pump is greater than or equal to 7.5kW or the diameter of the water outlet is greater than or equal to DN100, the fixed self-coupling device of the water pump can be used; when the power of the motor of the submersible sewage pump is less than 7.5kW or the diameter of the water outlet is less than DN100, a hose can be installed Mobile installation. When a submersible sewage pump is used for drainage of the sewage collection tank, a fixed self-coupling device for the water pump shall be installed to facilitate maintenance of the water pump. The drainage pump should be able to start and stop automatically and manually start and stop on site. Multiple water pumps can be operated in parallel and alternately, and can also be put into operation in sections.

Generally, the outlet diameter is selected according to the economic flow rate, and the outlet diameter is determined according to the flow rate. When the pipe diameter is less than 250, it is 1-1.2m/s, and when the pipe diameter is 250-1000, it is 1.2-1.6m/s. From a technical point of view, the speed of water flow It should not exceed 2.5-3.0m/s, and the minimum speed should not be less than 0.6m/s (to prevent deposition).

The inlet velocity is small, the advantage

1. It is beneficial to increase the NPSH of the device NPSHA, and the pump is not easy to cavitate;

2. The pipeline has little scour, especially the medium containing particles;

3. It is not easy to generate static electricity;

4. The pressure drop of the inlet filter is small;

5. In the same section, the medium flows evenly and the hydraulic loss is small.

The inlet velocity is small, the disadvantage

1. Under the same flow rate, the pipe diameter needs to be large and the pipeline cost is high;

2. For some easy-to-sediment media, the flow rate is too small, which may easily cause sedimentation and clogging;

3. The impeller inlet is large, the diameter of the mouth ring is large, and the leakage is large.

violent vibrating pump

It is possible to automatically rotate the rotor without obstacles, or the coupling is not well combined, and the bearing is worn out; it can also be rotated all loose, broken; or maybe it is because the pipe support is not strong, etc. Discern, repair, reinforce, to cause change.

Leaks or ventilation ducts

It can be used as a bolt that is not tightened tightly. If the leakage is not serious, the lime slurry caught in the center of the fire pump lime can be ventilated or seeped or mixed with tar. For temporary repairs, apply some damp mud or a soft towel. If you're leaking in the joints, then tighten the bolts by hand. Leakage mainly has to be disassembled from a new one.

Because the total pressure is too tight, the automatic rotor can be unobstructed, the fire pump or coupling is not well combined, and the bearings are worn out; Discern, repair, reinforce, to cause change.

Frozen water cannot enter the material, or the nominal protection of the shaft. Appropriate aggregate, clearing measures such as seal pipe obstruction can be taken. Total wear must be changed to a new one. The butter of the penetration unit, in order for the slang to be staggered, this can reduce the penetration. After the first circle is installed, the gland should always be tightened to adjust the thickness.

The fire pump does not absorb or does not drain the pump. The cause of the fire pump is stuck for the bottom valve, the level of filtered water is too high, all the silts, the fire pump is water-absorbing or water-permeable, and the impeller channel can be blocked by turning. It can be distinguished that the bottom valve is repaired, the blockage is eliminated, the steering is correct, the impeller is cleaned and other measures are taken to solve the problem.

The long-term operation of the fire pump puts a lot of pressure on the equipment, especially under the condition of continuous large flow, more attention should be paid to the maintenance and maintenance of the equipment. So what are the maintenance rules for fire pumps?

1. The long-term operation of the stabilized fire pump requires a certain bearing capacity. It is forbidden for the fire pump to continue to operate for a long time under the condition of cavitation and large flow, and the equipment motor is in the state of excessive flow for a long time.

2. Regularly check the tightness of the bolts at the joints of the fire pump installation. Loose bolts will cause severe vibration during operation of the equipment and affect normal use. At the same time, it is forbidden to start the fire pump in the dry grinding state, otherwise the damage to the mechanical seal will be serious.

3. It must be used within the specified working conditions of the fire pump, and regularly check the motor flow value of the fire pump to see if it is overloaded. Before the equipment is started, the electric motor pump can be rotated a few times to prevent the equipment from suddenly starting and causing parts to break and break.

4. The working temperature of the bearing is around 50°C, so a lubricating grease with good heat resistance and waterproof should be selected. Every time the stabilized fire pump runs for 500 hours, it needs to add lubricating oil. It is best to choose a suitable lubricating oil, which is heat-resistant and waterproof, and add it to the bearing part of the pump. When adding lubricating oil, keep it clean and free of particles, which can reduce the wear and tear of the fire pump during operation.

5. Mechanical equipment such as fire pumps are prone to wear and tear after long-term operation. It is recommended to arrange a thorough inspection every year. For severely worn bearings and vulnerable parts, disassemble and replace them if necessary.

Tip 1: Grinding is running-in. This is the basis for extending the service life of the engine. Whether it is a new engine or an overhauled engine, it must be run-in according to the regulations before it can be put into normal operation.

Secret 2: Purification means cleansing of oil, water, air and body. If the diesel and gasoline are impure, the precise matching body will be worn out, and the fitting gap will increase, resulting in oil leakage, oil dripping, lower oil supply pressure, larger gap, and even serious failures such as oil circuit blockage, shaft holding, and tile burning. ;If the air contains a lot of dust, it will accelerate the wear of the cylinder liner, piston and piston ring; if the cooling water is impure, the cooling system will be blocked by scale, which will hinder the heat dissipation of the engine, the lubrication condition will become poor, and the body will wear seriously; If the surface is not clean, the surface will be corroded and the service life will be shortened.

Tip 3: Feet are oil feet, water feet, and air feet. If the oil supply is insufficient or interrupted, the engine lubrication will be poor, the engine body will be severely worn and even burnt; if the cooling water is insufficient, the engine temperature will be too high, the power will drop, the wear will increase, and the service life will be shortened; if the air supply is not timely or interrupted , there will be difficulty in starting, poor combustion, power drop, and the engine cannot run normally.

Tip 4: Inspection That is, check the fastening parts frequently. Due to the influence of vibration, shock and uneven load during the use of diesel engines and gasoline engines, bolts and nuts are easy to loosen. The adjusting bolts of each part must be checked to avoid accidents that damage the machine body due to looseness.

Tip 5: Adjustment means that the valve clearance, valve timing, fuel supply advance angle, fuel injection pressure and ignition timing of diesel or gasoline engines should be checked and adjusted in time to ensure that the engine is in good condition, so as to save fuel and prolong the service life .

Secret six: use the engine correctly. Before starting, the lubricating parts such as shafts and bushes should be lubricated. After starting, wait until the water temperature is above 40°C before putting it into operation. Prolonged overloading or low-speed operation is strictly prohibited. Before stopping, unload the load and reduce the speed. After parking in winter, drain the cooling water when the water temperature drops to 50°C.

Observe and check frequently, find faults, eliminate them in time, and do a good job of engine maintenance at ordinary times, so that the machine can always be kept in good running condition. If you have the need to purchase fire pumps, please contact us by phone.

Causes and treatment methods of water pump leakage

1. The installation is too tight

Observe the planes of the dynamic and static rings of the mechanical seal. If there is serious burning, the planes turn black with deep traces, the sealant hardens and loses its elasticity, this is caused by over-tight installation.

Solution: Adjust the installation height. After the impeller is installed, pull out the spring with a screwdriver. The spring has a strong tension. After loosening, it will reset and move a distance of 24 mm.

2. The installation is too loose

Observe the machine seal, the plane of the static ring, there is a very thin scale on the surface, which can be wiped off, and the surface is basically not worn, which is caused by the loss of elasticity and the assembly of the spring, or the axial movement of the motor.

Solution: Adjust the installation height. After the impeller is installed, pull out the spring with a screwdriver. The spring has a strong tension. After loosening, it will reset and move a distance of 24 mm.

3. Poor water quality contains particles. Due to the poor water quality, the medium contains small particles and high hydrochloride content, forming the sealing surface or tension surface of the abrasive mill, causing grooves, grooves and other phenomena.

Treatment: Improve the water pressure or medium and replace the machine seal.

About the maintenance method of the water pump

During the long-term operation of the fire pump, phenomena such as wear of the bearing chamber, bearing position, cracks and rupture of the pump body, pump cavitation and erosion often occur. After the above problems occur, the traditional solution of the enterprise is to repair or repair after brush plating, but there are some shortcomings: the thermal stress generated by the high temperature of repair welding cannot be completely eliminated, and it is easy to cause material damage, resulting in bending or breaking of parts; The thermal stress after plating can cause material damage and part fracture. H electroplating is limited by the thickness of the coating, and it is easy to peel off. The above two methods use metal to repair the metal, and the "hard" state cannot be changed. For the hard fit relationship, under the combined action of various forces, it will still cause re-wear.