RVSPK 20,000 tank drawings

General plan

This album presents a group of ground tanks, consisting of two RVSPK 20,000 tanks, enclosed by closed earthen collapse or a fencing wall with a width of at least 0.5 m on the top, fencing options are presented on 1315 sheets of the album. Constructive decisions are made depending on local conditions. The distance from the edge of the collapse to the driveways is not less than 10 m.

Foundations and foundations.

The foundation and foundations of steel vertical tanks shall be made in accordance with the effective regulatory documents and the requirements of Section 3 of these Norms. Initial data for tank base design shall be the results of geotechnical surveys of site soils. According to the totality of these conditions, the sites for the construction of foundations for tanks are divided into favorable, unfavorable and very unfavorable. Geodetic grades shall be provided for monitoring the tank settlement during operation on the foundations, and at a distance of at least two meters from the tanks, in places where there is no influence of other structures, basic benchmarks shall be provided. Versions of the fundamental solutions for the design of the bases for the tanks are given on 811 sheets of the album.

Steel tank structures.

The tank belongs to 1 class of responsibility (hazard) and I increased level of responsibility according to GOST 2775188. Tank loading cycle is not more than 350 cycles per year.

Main design provisions adopted during the design and tank indicators:

1. Product density 0.9 t/m3 (during hydrotest - 1.0 t/m3)

2. Design value of snow cover weight not more than 2.4 kPa

3. Standard wind load 0.38 kPa

4. Maximum product temperature + 50 ° С

5. Design seismicity of construction area up to 8 points

6. Tank diameter 45.60 m

7. Tank wall height 11.94 m

8. Product mirror area 1,633 m2

9. The temperature of the coldest days with a security of 0.98 is not lower - 50 0С.

10. Potential usable tank capacity 15,090 m3

Materials

Requirements for materials for tank structures are given in Section 5 of this Code.

Material of a wall and okrayek the bottoms - steel of class C345 of brand 09G2S12, the central part of the bottom, floating roof, katuchy ladder of the tank - steel of class C255 of St3sp5 brand. Material of stairs, platforms and fences - steel of class C235 of grade St3ps4.

Tank Design

Requirements for steel structures of the tank are given in Section 2 of this Code.

The wall of the sheet tank is 1990 x 7990 mm.

The bottom of the tank is sheet made of sheets 1990 x 7990 mm.

Tank roof - floating, consisting of enlarged prefabricated units. Assembly of blocks is performed at the installation site.

In the upper part of the wall there is a stiffening ring used as an annular platform. For lifting to the annular platform there is an annular ladder with fixation to the wall. To descend to the floating roof from the circular platform, a rolling staircase is used.

All welding and installation works shall be performed according to the welding and installation works project.

The standard life of the tank is not less than 50 years.

The overhaul cycle is at least - 20 years.

The service life of the internal anticorrosive coating is at least - 20 years.

Quality control of welds

Requirements for quality control of welds are given in section 2.10 of these Norms.

100% of all welded joints of the tank and floating roof shall be subject to visual and measuring inspection.

All welded seams of the bottom and floating roof along their entire length shall be controlled for impermeability by vacuumizing.

Quality control of welds by physical methods (radiography and ultrasonic):

- bottom seams at a distance of 250 mm from the outer edge are subject to 100% radiographic inspection;

- vertical seams of 1-2 wall belts are subject to 100% radiographic and ultrasonic inspection;

- the remaining vertical seams and all horizontal seams of the wall belts are subject to 100% ultrasonic inspection.

- seams of boxes (compartments) and blankings of struts are subject to 100% overpressure control.

The remaining welded joints and steel structures of the tanks shall be inspected within the scope specified in Table 2.13 of this Code.

Tank equipment

Requirements for tank equipment are given in Section 4 of this Code.

Two tanks with a capacity of 20,000 m3 of sheet design with a floating roof for oil were accepted for installation.

The area of accommodation of tanks with flammable liquids (LFL) forming with air explosive mixtures of category IIA of group T3 according to PUE belongs to class B1g by explosion hazard.

Each RVSPK 20 000 tank is supplied complete with floating roof, sealing gate, circular ladder for lifting to the tank, rolling ladder for access to the roof, skylights, mounting hatch and hatches of eyes in the I and II belts, annular platforms along the perimeter of the upper belt, platforms with ladders to hatches in the II belt and for equipment maintenance.

To ensure the required operating modes of the tanks, explosion-proof equipment is installed on them.

All equipment shall be accepted as "U" or "CL" category 1 depending on the climatic zone, in accordance with GOST 1515069.

Installation of equipment on the tank housing shall be carried out taking into account the distance between vertical seams of the tank wall and welds of reinforcing sheets of equipment nozzles not less than 250 mm, and between horizontal ones - not less than 100 mm.

The number and diameters of the receiving and distributing branch pipes are selected based on the provision of the specified oil pumping capacity, their number and diameters are given in Tables 2.6 and 4.4:

- maximum permissible speed of floating roof movement (lifting and lowering) not more than 6 m/h;

- liquid flow rate through one receiving and distributing branch pipe up to 8.8 m/s.

In order to erode and prevent accumulation of paraffinic sludge on the bottoms of tanks without their decommissioning and without violation of the technological mode, installation on each tank by a screw stirrer of the type "Diogen700" is provided.

Due to limitation of forces transmitted to the tank wall

RVSPK 20 000 from process pipelines at foundation settlement, displacement of tank wall from hydrostatic pressure and temperature deformations for compensation of relative movements of pipeline-reservoir system is provided for installation of bellows compensators of rotary type.

Connection of the compensating system to the tanks on one side and to the main gate valves on the other side in fully assembled form shall be carried out after installation and fixation of the gate valves on the foundations using a fitting insert. Closing seam temperature is 00 С - + 200 С.

The installed acceptance unit together with the compensators shall be subjected to hydraulic test in accordance with PB 0358503 for strength with pressure Risp. = 1.25 Rrab. and on tightness pressure Risp.=1.0 of MPa during time necessary for survey.

Piping after root valves shall be tested together with process pipelines for strength at pressure of Risp. = 1.25 Rrab. and on tightness pressure Risp. = Rrab. =1.6 MPas.

Corrosion protection of equipment, above-ground pipelines and supports is carried out together with the tank. Protection against corrosion of underground pipelines is performed by protective coating of reinforced type as per GOST R 5116498.

Fire fighting and tank cooling.

Requirements for the design of foam fire extinguishing and water cooling systems of tanks are specified in Section 6.4 of these Norms, in SNiP 2.11.0393, SNiP 2.04.0185, SNiP 2.04.0284 *, as well as in the design standards for automatic fire extinguishing systems at facilities of Transneft's subsidiaries.

Automatic combined fire extinguishing systems (hereinafter referred to as ASKPT) are used to extinguish fires in tanks with floating roofs.

Automatic systems of combined fire extinguishing provide supply of low-multiple film-forming foam simultaneously to zone of sealing gate (from above) and to lower part of reservoir, i.e. directly to oil (combined method) and protect vertical steel tanks with floating roofs.

Estimated fire extinguishing time for automatic foam fire extinguishing systems is not less than 10 min. Inertia of stationary fire extinguishing systems shall not exceed three minutes.

Ground tanks with floating roofs shall be equipped with stationary cooling units.

The estimated cooling time of the tanks (burning and adjacent to it) should be taken for ground tanks when extinguishing a fire by an automatic system - at least 4 hours.

The design of internal and external wiring of water, foam pipelines, pressure units of foam generators, units for connection of mobile fire equipment of foam fire extinguishing and tank cooling systems is carried out in accordance with the requirements of the current regulatory documents in the field of fire safety, as well as the design standards for automatic fire extinguishing systems at the facilities of Transneft subsidiaries, agreed with state supervisory authorities.

Grounding, lightning protection and static protection

The lightning protection of tanks is designed in accordance with the requirements of RD 34.21.12287 and the Regulations "On the Design and Operation of an Integrated System for the Protection of Tank Farms of Oil Pumping Stations and Oil Depots of JSC AK Transneft from the Effects of Dangerous Lightning Factors, Static Electricity and Sparking."

In terms of lightning protection, tanks belong to category II and must be protected from direct lightning strikes, electrostatic and electromagnetic induction, drift of high potentials through pipelines.

The lower belt of the tank wall is connected through current leads to grounding electrodes installed at a distance of not more than 50 m uniformly along the perimeter of the wall. Among themselves to make connection of conductor cables of the tank and ground wires brass bolts, nuts and washers of M 16. Each connection (wall - current collector - grounding conductor) must have a pulse resistance of not more than 10 ohms.

Current leads and earthing leads should be made of steel rolled stock with dimensions in section 4 x 40 mm2.

Grounding is performed in accordance with the requirements of PUE Edition 7 Chapter 1.7 by horizontal grounding connectors made of strip steel laid in the ground at a depth of at least 0.5 m along the perimeter of the tank in the frame at a distance of 1 meter from the soil foundation. The grounding circuit of the tanks is connected to the common grounding circuit of the pump station by beam electrodes made of strip steel at least in two places on opposite sides. Grounding device resistance shall be not more than 4 ohms.

Protection against direct lightning strikes must be carried out by separate lightning receptors. The area of lightning receptacle protection shall include the space above each branch pipe located on the floating roof, limited by the cylinder by a hemisphere with a radius of 5 m in accordance with RD 34.21.12287 * para 2.18.

All lightning arresters are connected to the common grounding loop by 4x40 mm2 strip steel.

The project "Tank Equipment" has developed measures to protect the tank from electrostatic and electromagnetic induction.

To remove static electricity charges and equalize potentials, the floating roof of each tank should be connected to the walls with three evenly distributed bridges from the 16 mm2 REAG cable in accordance with the requirements of the Regulations "On the Design and Operation of the Integrated System...." Attach the tip to the cable core by soldering. Put the heat-shrinkable cuff (tube section) on the tip shank and cable sheath.

During operation the contacts shall be checked, cleaned and tightened periodically.

Production sewage system

Production sewage systems in the frame and tank farm shall be performed according to RD 15339.4-113-01 and SNiP 2.04.0385.

The territory in the map should have a slope of at least 0.005 towards rainwater wells, two rainwater wells (DKh) are installed in the map.

Rain receivers are equipped with shut-off devices (flaps), driven from the fencing shaft, which allow directing contaminated water, under normal conditions, to the production and rain sewage system.

Gate valves are installed in wells (CP) at the outlet of sewage system from the tank farm frame outside the collapse limits.

After wells with gate valves there are provided wells with hydraulic gates (PG) with a liquid column height of at least 0.25 m.