Equipment for discharging operations

Clappers are designed to prevent the loss of oil and oil products from the tank in the event of a rupture of process pipelines or failure of the shut-off bodies placed on it. Flappers produce two types: controlled and unmanaged, the latter are rarely used, are installed only on the discharge lines. They open under the pressure of oil from the process pipeline and close at the end of the pumping under the weight of the flapper cover. Controlled crackers are installed on the junction pipes inside the tank on the suction and delivery pipelines. Clappers with conditional passage up to 300 mm are manually driven from the upper control mechanisms (MUV) located on the tank roof or from the control mechanisms (MU) located on the tank wall. The clappers are opened with the help of cables (main and spare) made of stainless steel with a diameter of 5 -8 mm. The main cable from the control mechanism is connected to the eye of the lever of the main or bypass valve, and the spare cable is displayed in the skylight, or it is provided for in the design of the upper control mechanism.

The main problems that cannot be solved by the use of receiving-distributing pipes and solved with the help of receiving-distributing devices can be reduced to the following:

1. an increase in the accumulation of sediments on the bottom of the tank in products prone to delamination and sedimentation leads to difficulty in the production of commodity operations, additional costs for cleaning the tank and an increase in the corrosiveness of sediment, leading to a decrease in the service life of the first belt and the bottom of the tank. Reducing the height of the sediment is achieved by the hydromechanical effect of the jet of the injected product on the sediments using slot-type dispensers.
2. movement of oil products through pipelines with a volumetric electrical resistance of more than 109 ohm m (for example, gasoline) leads to their electrification and, if it enters the tank, it can cause static electricity to discharge and ignite the vapor-gas medium in the tank. The intensity of electrification is higher, the smaller layer of oil product is above the injected fluid, therefore the supply of oil to the tank from a height of 200 mm from the bottom of the tank with an open stream and with splashing is not allowed.
3. an increase in the turnover of petroleum products in modern conditions leads to the need to reduce the non-rotatable volume of petroleum products in tanks and more efficient operation of tanks. Therefore, they strive to reduce the level of impermeable residue of the oil product and the receiving-distributing devices perform reduced to the bottom of the tank.

In addition, there are a number of requirements of regulatory documents prohibiting the reception and distribution operations with significant speeds. Thus, the filling of tanks is prohibited with speeds exceeding 1 m / s until the pontoon is lifted from the supports (in the RVSP) or until the tank is filled with petroleum products with the PDP being flooded (in the RVS). This problem with the intensification of operations or in the absence of adjusting the flow rate at the pump is solved by diffuser receiving and dispensing devices or devices with a decrease in the speed of the oil product in length organized in other ways. Consequently, the main requirement for receiving-distributing devices is the flow rate at the outlet of the device.

The PRU transfer and dispenser device consists of a branch, an umbrella, a divider and can be equipped with a locking device. The outlet is connected to the PDP of the tank, on the other hand an umbrella is attached to the outlet, and the divider is installed on the bottom of the tank under the umbrella. The structure of the type of PRU also include valves.

One of the most loaded elements in the design of the tanks is the insertion zone into the tank wall of the receiving and receiving pipes experiencing low-cycle loading from the pipeline side and moving away from thermal deformations of the pipeline. During installation, it is forbidden to firmly connect the flow divider installed on the bottom of the tank and the umbrella located on the branch, which is associated with a possible significant movement of the wall. In addition, the existing control gears (two turns of 90 degrees) have a sufficiently large hydraulic resistance (especially with the placement of the rotary damper actuator elements and itself in the pipeline). The reduction of hydraulic resistance is achieved using a profiled flow between the divider and the umbrella, as well as the use of valves. In order to ensure the durability of the tank and the electrostatic safety, the PRU should have such a design and be positioned so that the flow of oil entering the tank at high speed does not affect the thrust angle of the junction between the wall and the bottom of the tank.

Analyzing the above facts it is clear that the receiving and distributing devices of the PRU type do not ensure the safe operation of tanks.

The technical solution enclosed in the combined receiving and distributing device (SUPPR) with the combined functions of several devices is aimed at ensuring the integration of the useful functions of the PRD, the CP intake-safety device and the bottom erosion scouring device with an adjustable jet feed. SUPR are made of the following types: to reduce the accumulation of bottom sediments during operation of reservoirs with exfoliating oil products with an adjustable jet velocity at the outlet of SUPR. to ensure electrostatic safety when filling any type of reservoir with highly electrifying petroleum products and reduce the speed to that required by the regulatory documentation when filling the RVSP or RVSPK. It is possible to combine different types of supr in one device when using tanks for different petroleum products. In general, the SUPPR contains a housing - a tap that gradually decreases towards the bottom of the tank and, as it decreases, changes the cross section from a circular one at the point of attachment to the receiving and dispensing pipe of the device to the slotted nozzle at the bottom open end of the case. At the same time, due to the flow direction and reduced full hydraulic resistance compared to the FRA, the load on the tank wall is reduced. To compensate for the displacement of the tank wall relative to the bottom, the SUPR includes an intrinsically safe housing support on the bottom of the tank, and a rotary compensator can be provided at the point of connection of the SUPR pipeline to the PRP. SUPR devices are designed so that they can be easily installed on tanks with pontoons already installed through manholes in the wall. In the design of SUPR of the first type, depending on the thickness of the sediment layer and, therefore, on the required speed for its erosion, the size of the slit is regulated by the position of the shutoff member. When storing and pumping petroleum products, the valve can act as a lid of the CP or gate of the PRD.

When storing kerosene due to the difference in its density with the density of water, the latter drops to the bottom of the tank. The use of aviation kerosene even with a small admixture of water is unacceptable. For pumping high-quality fuel and oils from the upper layers of the tank in order to prevent the supply of contaminated and waterlogged fuel, floating ROM intake devices are used.

The ROM is installed on the receiving-distributing pipe using the hinge of the pipe piece and moves along the tank height when the loading level changes with the help of floats calculated from the conditions of preserving the buoyancy of the ROM at a given product density, taking into account the mass of the moving part and the moment of pipe movement along the pipe hinge supports.

The ROM consists of a moving part and a fixed one. The movable part is mounted on a movable pipe hinge outlet and includes a carrying float (floats) and a pipe.

The fixed part of the ROM consists of a lodgement located on the bottom of the tank on which the intake pipe is located in its lower position, which prevents the intake of commercial water at the minimum level of filling in the tank and the contact of the parts of the ROM with the commercial water, increasing the service life of the structure. The shape of the intake pipe end of the ROM eliminates the ingress of commercial water into the pipeline and helps reduce the speed in it. To ensure lateral stability of the moving part (in the direction perpendicular to the plane of movement), the pipe is fixed with braces to spherical joints mounted on the bottom or wall of the tank.

In order to avoid ROM elevation at a greater angle of friction (70 °) at which the pipe cannot return to its original (horizontal) position, the ROM elevation angle limiters are provided in the ROM construction (up to 55 °) in the form of a cable of fixed length fixed to the bottom of the tank, or the angle limiter installed on the hinge pipe.

In emergency situations (in case of damage to the tempering pipeline or the tank valve), product leakage from the tank can be prevented by using an emergency control mechanism for lifting the suction pipe in the form of a cable, one end attached to the end of the pipe, and the other to the light hatch / located on the tank roof. .

• Mountain Encyclopedia . Drainage and filling devices. - M .: Soviet Encyclopedia , 1984-1991 - in 5 volumes
• Tanks for petroleum and petroleum products: volume 1. Designs and equipment: a textbook for universities / FM Mustafin, R. A. Zhdanov, MG Karavajchenko and others. - SPb .: Nedra, 2010. - 480 p.
• Yu. D. Zemenkov, N. A. Malyushin, L. M. Markova, A. E. Loshchinin. Technological pipelines of oil depots, reference edition, Tyumen - 1994
• F. F. Abuzova, I. S. Bronshtein, V. N. Novoselov and others. Combating oil losses of oil products during their transportation and storage. M.: Nedra - 1981—248 p.

• Oil storage
• Sampler
• Breathing fittings