uPVC Casing Pipe

PVC-U Well Casing and Screen Pipes for Water Well Construction

Highest Quality uPVC Well Casing and Screen Pipes for Water Well Construction

Casing Pipes & Screen Pipes are used for Bore Hole / Bore Well application. It prevents the earth to fill the Bore well and the Screen allows the water to percolate in the well which can be pumped with the pump.

Vinyl uPVC Casing & Screen Pipes has a higher density than water that provides a clear advantage in good construction. Its yield stress of 55Nlimm is comparatively high. The modulus of elasticity is also high enough to achieve excellent stiffness in pipes preventing undesired deformation of the pipe.

  • Corrosion & Bacteria Resistance.
  • Resistant to all substances dissolved in natural ground waters.
  • Resistant to aggressive and highly concentrated acids and salts.
  • Completely resistant to bacteria in water and soil.

Material

PVC-U, unplasticised polyvinyl chloride is an ideal material for manufacturing well pipes as it is impervious to corrosion and chemical action, easy to handle and install, light in weight, non-toxic, non-conductive. Its long service life makes it an economical choice over other materials.

Screen Permeability

The possible production capacity of a well basically depends on the following factors:

  • Permeability and yield of the water-bearing strata
  • Permeability of the filtering gravel
  • Permeability of the good screen
  • Entrance velocity of the water at the screen

Standard slot width range showing average percentage open area

Average percentage of open area
Standaard Slot Screen (lengtwise) Continuous Slot PVC Screen (CSS)
4% 0.30 mm 0.30 mm 6%
5% 0.40 mm 0.40 mm 8%
6% 0.50 mm 0.50 mm 10%
9% 0.75 mm 0.75 mm 15%
11% 1.00 mm 1.00 mm 20%
13% 1.25 mm 1.25 mm 25%
16% 1.50 mm 1.50 mm 30%
20% 2.00 mm 2.00 mm 40%
25% 3.00 mm 3.00 mm 50%
28% 4.00 mm

PVC-U Well Casing and Screen pipes for Water Well Construction

Introduction

Water covers almost three quaters of the earth’s surface and a major portion of this is found in the oceans or frozen in the Polar Regions. Only a small percentage of fresh water is available as surface water in lakes, rivers, streams and as ground water. Ground water is the nite source and it must be exploited very carefully.

The past fifty years witnessed a global expansion of the water well industry particularly as extraction of water from the wells has become lifeline of industry, agriculture,and drinking water supply in cities, towns and villages.

Well construction products, therefore, play an important role to ensure the highest quality, efficiency and screens were the natural choice of well design engineers and drillers. However this material was not always found to be suitable, particularly in conditions where rapid corrosion of rapid pipes, deterioration of screens or formation of bacteria resulted in abandonment of the well and worse stillto contaminates the store.

Synthetic material that belong to a family of thermoplastics have proven to be the most superior materials for well construction. Among others, unplasticised Polyvinly chloride (u-PVC) that is ieally suited for use in well construction also belongs to this familly of thermoplastics.

PVC-U has higher density then water that provides a clear advantage in well construction. Its yeild stress of 55N/mm is comparatively high. The modules of elasticity is also high enough to achive excellent stiffness in pipes preventing undesired deformation of the pipe.

PVC-U is resistance to all substances dissolved in naturalground waters.PVC-U is also resistant to aggresive and highly concentrated acid and salts. Its resistant covers a pH range of water between 2 & 12, due to which the chemical used, for cleaning, devloping and regenrating the wells (both organic and inorganic) do not aect the PVC-U well pipes. PVC-U is completely resistant to bacteria in water and soil.

PVC-U Well Casing and Screen pipes for Water Well Construction

Tensile Strength

The tensile strength required can be calculated on the basis of pipe weight. In addition to the pipe weight, gravel that gets suck on the joints during the assembly and settlement phase should be considered in design calculations. The lower load bearing capacity of screen pipes with slots should be considered when the scree nular spaces, developing the well or when pumping (due to large differences in water level). The eect of such pressures cannot be precisely determined. When sinking pipes through clay layers, additional compressive forces are exerted due to swelling clays. This can happen at any depth and in extreme cases may cause considerable strain on the material surface. The values indicated in the tabels of this broucher are based on the minimum wall thickness of the pipes, their diameters and material composition.

Impact of Temperature

Temprature conditions prevailing during the laying of PVC-U well pipes will inuence the mechanical properties of the material. High temprature between 30° C and 40° C as indicated by the creep strength in realtion to time, the PVC-U material properties provide sucent safety factor for the intended use. It is however important to determine te other inuences while encasing the well pipes with concrete to seal the drill holes. Temprature increases can b caused by the hydration heat of concrete. Calculations however show that these tempratures do not normally exceed 15°C, with the temprature of unset concrete reaching approx. 18°C, the temprature within the seal will be slightly more than 30°C and that is within the optimum limits.

casing pipe

VINYL uPVC Screen & Casing Pipes Accessories

The following accessories, adaptors and Transition fittings in various sizes and types of joints are available
to complete well installation.

 

End Cap
Reducer
Centering Guide
Top Cap
Lidting Cap
Wooden Clamp
Split Clamp
Transition Fittings

Types of Joint System

Types of Joint System

METAL CASING & SCREENS
VINYL PVC WELL CASING & RIBBED SCREENS

METAL CASING & SCREENS & VINYL PVC WELL CASING & RIBBED SCREENS

  • Due to local action and corrosive soil nature the life of tube wells is as low as two years
  • Slot Openings get enlarged and silting starts due to erosion in the screens.
  • More than 50% of slot opening is obstructed by Filtering Media (Gravel Pack) hence low permeability.
  • Screen slot widths can not be made to suit aquifer sieve analysis for proper design of the well which cannot be avoided.
  • Metal casing and screens are heavy, thus making installation cumbersome and tedious.
  • Metal Casing require special equipments like welding sets and generator sets for assembly and erection.
  • Due to its weight, vertically can not be maintained.
  • Vinyl casin Pipe & Ribboned Screen Pipes are manufactured out of quality PVC compound and PVC being an inert material are totally unaffected by corrosion.
  • Slot openings are not subjected to erosion hence they do not offer any resistance to flow.
  • Due to the Ribs on the screen are FILTERING MEDIA (Gravel Pack) is kept 2 mm away from the slot opening and this increases the permeability.
  • Manufactured with slot widths ranging from 0.2mm to 3mm to suit the aquifer ssieve analysis which helps engineers to design the well to give better life and yield.
  • The specific gravity of PVC being 1.4, weight is only 1/5th of steel casing and screens. This makes it easier to handle and install.
  • Vinyl uPVC Screen Pipe & Casing Pipe are manufactured with socket and and spigot ends with suitable locking, which requires no special equipments to assemble and install.
  • Vinyl CASING and RIBBED SCREENS are supplied with centering guides to maintain verticality of the well.
  • Total Installation with VINYL WELL CASING AND RIBBED SCREENS will be substantially cost effective when compared with conventional mild steel casing and screens.