Introduction of LPG Spheres:
We are exporter and manufacturer of LPG SPHERE, LPG Spherical Tanks at cheap cost. LPG Sphere volumes range from 500 M3 to 8500 M3 are suitable for Butane, Propane as well as Butane – Propane mixtures i.e. LPG. The LPG Spherical tanks are designed as per ASME Sec. VIII Div.1, ASME Sec. VIII Div.2 and BS 5500, Codap 2000, AS 1210 and other international codes. We have executed storage facility including Mechanical, Civil, Piping, Instrumentation and Electrical.
We BNH Gas Tanks undertake the Project Execution on LSTK / EPCC (Engineering, Procurement, Construction & Commissioning) basis.
The scope of EPCC Contracts includes:
• Design and Detailed Engineering
• Fabrication, Testing, Procurement, Erection, of Piping and Spherical tanks.
• Safety measures like Fire Fighting etc.
• Supply and Installation
• Ground Improvement & Civil works
• Electrical and Instrumentation work
We manufacture LPG spherical tanks / Horton spheres for storage of LPG, Propane, Ammonia, Ethylene and other gases as per ASME Sec.VIII Div. 1 and 2, PD 5500 and other international codes. We have in-house design department, which is capable of designing Spheres with international codes such as ASME, PD 5500, DIN. The volume range from 200 m3 to 5000 M3 .The Spheres are provided with all accessories like safety fittings ,valves , pipelines, Excess flow valves , internal valves as per requirement . The above photographs shown manufacturing of LPG sphere consisting of various activities like Pressing of plates at shop , Pre fabrication of Equator and crown plates , Legs or columns for sphere , Radiography welding , NDT testing , Erection at site , Hydrotesting and coating of LPG spheres.
Total Project Commissioning for BULLET:
• 5 x 3000 cum. LPG Sphere
• 5 x 2500 cum. LPG Spherical tank
• 4 x 1500 m3 LPG ball tank
• 4 x 5000 cum. Ammonia Sphere
• 2 x 2000 cum. LPG Horton sphere.
• 4 x 8500 cum. LPG Spheres
• 4 x 4200 cum LPG sphere
Design Code ASME, PD 5500, AD Merkbaltter and others.
Design Pressure 17.16 Bar
Design Temperature -20 Deg C to + 55 Deg C
Volume 500 M3 to 8500 M3
We use various international design codes for designing of LPG Sphere as follows:
PD 5500: Specification for unfired Fusion welded pressure vessels
EEMUA: Guide for design, construction and use mounded horizontal cylindrical vessels for pressurized storage of LPG at ambient temperatures
EEMUA 190: Selection criteria LPG storage systems
ASME sec. VIII Div. 1 and 2
Material of construction: SA 537 CL 1, SA 516 GR 70, BS 1501-1 225 490 A, EN 10028-3 P355NL2 AND OTHERS
Safety Design Features
• Concept of a Single nozzle in the liquid Zone.
• Remote operated fire-safe emergency shut off valves
• Sloping and elongating the liquid nozzle.
• Redundancy of level instruments
• Manhole at top of sphere.
• Insulation/fireproofing of sphere & supports.
• Paving and sloping of diking / impounding / ground underneath
• Gas / fire detection, deluge and sprinkler system.
Advantages / Comparison of LPG Sphere and LPG Mounded Bullets
IS MOUNDED BULLET FOR STORING LPG IS BETTER THAN USING SPHERE? AND WHY?
The choice between a bullet and a sphere is a matter of economics and project logistics. So one is better than the other only in the matter of which has a cheaper overall installed cost.
The sphere of course uses less material than a bullet for the same amount of liquid storage but is somewhat more difficult to fabricate. The diameter for shipping of a storage tank is in the order of 10 to 14 feet depending on the method of transport. This would limit a sphere's storage capacity if it is shop fabricated. For a 10 foot diameter tank, you can get 10 or more times the storage in a bullet than a sphere. For this reason, you usually only see spheres used for very large volumes (maybe in the order of 300,000 gallons or more) because they must be field fabricated to compete with the bullet in cost.
For smaller storage tanks, the bullets are preferred because they can be shop fabricated and more easily transported.
COMPARISION OF LPG SPHERES WITH LPG STORAGE TANKS:
1) Least initial investment and financial risk in case of LPG multiple storage tanks of as compared to sphere of similar or larger volume.
2) LPG sphere of same volume needs more time for construction as compared to LPG multiple storage tanks.
3) LPG Multiple LPG storage tanks makes the project faster, economical, easier and will in turn help the company to start the terminal as soon as possible which in turn will generate good immediate returns.
4) LPG Storage tanks are much safer since it weight is distributed evenly on a larger area thus reducing chances of collapse as compared to sphere, especially in small islands porne to earth quakes, cyclones and Tsunami as can be verified from the recent incident in Japan where a row of LPG sphere went under severe fire condition.
5) Multiple LPG storage tanks have an added advantage that the load is distributed over a larger area thus the problem of uneven settlement / collapse is largely reduced.
6) In case of installations with Multiple LPG storage tanks if there is any problem / maintenance / repair / breakdown of any one tank the outlet and inlet valves of the same can be closed and the tank can be isolated, also in case of emergency the LPG product in the tank under repair / maintenance can be easily transferred to another tank located in the same plant thus increasing safety of the plant. Whereas in case of sphere if there is any problem with the sphere or its valves or pipeline the entire plant comes to a stand still (This is a loss to the company in terms of business loss, product loss, as well as extra demurrage that the company may have to pay to the shipping company if unfortunately the LPG ship also arrives the same time when the sphere has generated a possible breakdown). But in case of multiple storage tanks even if one of the tank generate a possible breakdown and the LPG ship also arrives the same time still the LPG from the ship can be unloaded to the remaining tanks and the company will have to incur least loss due to ship demurrage.
7) Though there is a common notion that for the same volume a sphere has the least surface area and least thickness and hence lesser weight and less cost but our past experience suggests that weight saved in making a sphere as compared to storage tank is lost as wastage in the development of various sections (petals and crown) thus leaving little or no benefit of the weight saved.
8) The fabrication cost increases considerably in case of sphere as compared to multiple LPG storage tanks , since the sections have to be pre fabricated at shop, shipped to site, adjusted, assembled and welded at site piece by piece in proper sequence, heat treated, radiographed and tested at site. Fabrication of sphere requires lot of time since the petals / sections are required to be assembled piece by piece in proper sequence and completion of one stage is entirely dependent on completion of the earlier stage as so on and so forth. More over there is a continuous requirement of close monitoring, blockage of all construction equipments and manpower till the entire completion of work sequence by sequence, this makes the fabrication of sphere still more costlier and time consuming as regards to blockage of manpower, machinery rent etc.
9) Sphere once fabricated cannot be moved or relocated from one place to another and if in case any relocation (due to sale of plant or plant relocation) is required the sphere has to be cut into several small pieces and transported to site and then reassembled and re-fabricated at new site this is as good as manufacturing a brand new sphere at site and hence the after sale value of a sphere is much less and as compared to lpg storage tanks which can be sold out for good returns.
Why is LPG stored in spherical tanks?
A sphere is a very strong structure. The even distribution of stresses on the sphere's surfaces, both internally and externally, generally means that there are no weak points. That's why a drop of water forms a spherical shape when under free fall, in short, it achieves a shape where all the resultant stresses neutralize when no external force (gravity) is acting on it. Moreover, they have a smaller surface area per unit volume than any other shape of vessel. This means, that the quantity of heat transferred from warmer surroundings to the liquid in the sphere, will be less than that for cylindrical or rectangular storage vessels. Thus less pressurization due to external heat.