Quality Control


HB brand pipe fittings follow the plus tolerance of BIS specifications. HB brand pipe fittings are approved & regularly used on all the major govt., semi govt., commercial and domestic piping systems through out India. They enjoy a reputation of being the ULTIMATE IN QUALITY. This reputation has been made possible by company’s image of producing consistently accurate and reliable quality fittings combined with their very efficient sales and after-sales network throughout India.HB brand pipe fittings are subjected to rigid inspection at various stages of manufacturing to ensure their reliability. Hence they are being used for industrial, agricultural, domestic, commercial and other piping installations on ground, underground and concealed without the fear of faults and the rectifications there of.


A brief Description of brand HB pipe fittings with their code designations are as follows :

(a) Elbow & Reducing Elbow A1 (h) Side outlet Tee (4 Way) Za2
(b) Tee & Reducing Tee B1 (i) Short Bend (Long sweep Bend) G4
(c) Socket & Reducing Socket M2 (j) Plug T8
(d) Union U1 (k) Bushing N4
(e) Hex Nipple N8 (l) Backnut P4
(f) Cross C1 (m) Male & female Elbow A4
(g) Side outlet Elbow (3 Way) Za1 (n) Tank Nipple  


Size Designation :

Size designations are determined by the nominal inch sizes of threads at the outlet of fittings. HB brand pipe fittings are normally manufactured from 1/4″ to 8″ sizes.

Equal Fittings :

The fittings of which the nominal inlet & outlet diameters are of the same size are referred to as equal fittings.

Unequal Fittings :

The fittings of which the nominal inlet and outlet diameters differ are referred to as unequal fittings. To denote the sizes in case of such fittings, the bigger diameter is indicated first and then the smaller diameter e.g. 1″x3/4″ or 1″x3/4″x1″.

Union :

Unions are flat-seated & are supplied with rubber gaskets.

Specifications :

HB pipe fittings conform to the following specifications.

Dimensions :

Malleable cast iron pipe fittings as per IS 1879 – 1987 (Part 1 to X).

Material :

Black heart malleable cast iron as per 14329-1995 grade BM -300

Threads :

Threaded as per IS : 554-199 parallel female & taper male threads to bear pressure tight joints.

Finish :

Hot dip galvanized finish tested in accordance with provisions contained in IS : 2633-1986 & IS : 6745-1972.

Quality Controls :

To control and maintain the required quality, the following tests are performed :

  • Raw materials such as pig iron, steel scrap and zinc are tested for their required chemical compositions prior to melting, in a well equipped testing laboratory. Molasses & sand are also tested for their required properties./li>
  • Raw castings are chemically tested for the required chemical compositions.
  • Galvanized casting are tested to ensure that the zinc coating is not less than the specified 610 gms/m as per IS : 4759-1996.


  • Raw casting are subject to strict visual inspections to ensure that they are sound, clean, free from porosity, blow holes, hard spots, cold shuts, distortions, misruns and sand drops etc.
  • Annealed, grinded and shot blasted casting are inspected for cracks and distortions.
  • Galvanized castings are inspected to ensure that the zinc coating is smooth, clean, uniform, free from acid spots, black spots and pimples.
  • Thread inspections are carried out to ensure that the machined fittings are free from defects on threaded portions such as thin threads, broken threads & pin holes.

(C) MECHANICAL TESTS (By Sampling Method) : To ensure that the fitting have acquired the requisite properties, the following mechanical test are performed.

  • Malleability Test : To ensure that the fittings have acquired proper malleability,
  • Tensile Test : To ensure that the fittings are annealed & have attained the required tensile strength & elongation.
  • Pressure Test : To ensure that the fittings are leakproof when subjected to internal fluid & air pressure.

(D) METRO LOGICAL INSPECTIONS : Metrological inspection is done to ensure that the fittings have acquired correct alignment, overall diameters, wall thickness with the help of suitable thread gauges & micrometers etc.

  • Marking : HB is a registered trade mark, appears on all fittings except where it is not possible for technical reasons.
  • Packing : HB brand pipe fittings are packed in double gunny bags with an additional polythene bag inserted to ensure their complete protection in all weather conditions. Details of standard per bag packing can be furnished on request.
  • Technical Parameters : The following table highlights the technical superiority of HB brand pipe fittings vis-a-vis the national & international standards.
Specifications HB BIS ISO JIS BS
Tensile strength (Min.) Mpa 320 300 300 280 280
Elongation (Min.) (%age) 10 6 6 5 6
Zinc coating (Min.) (gms/m2) 810 610 450 - 450
Hydraulic Working Pressure (Max.) Mpa 2.9 2.1 2.0 2.0 1.4
Hardness (Max) (HB) 120 to 140 150 - - -
Angle Tolrance Degree (+/-) 0.40 0.50 0.50 0.40 0.45



Malleability : HB brand pipe fittings are manufactured under strict process controls in melting & heat treatment which enable them to achieve better malleability, ductility alongwith requisite strength, The right combination of strength and ductility ensure them to resist higher pressure without any breakages or leakages.
Accurate Threading : HB brand pipe fittings are threaded on special purpose machines to ensure close tolerance limits of thread dimensions which lead to their close contacts with pipes, valves & cocks etc. and as such there remains no chance of leakage.
Chamfering : HB brand pipe fittings are chamfered slightly on every thread opening to enable easy and correct entrance of pipes, valves & cocks etc. it also ensures easy engagement of first thread.
Hot Dip Galvanizing : Pure zinc is used employing hot dip technique for galvanising HB brand pipe fittings. Hot dip galvanising rechnique ensures zinc coating to be uniform, smooth, clean, free from black spots, acid spots and pimples. Hence the resultant thick & continuous coating of zinc gives them extra protection against environmental corrosion.


HB brand pipe fittings achieve the highest standards in malleability, thus they withstand the higher tightening force applied. Hence they do not crack or break while screwing on to pipes, valves and cocks etc. Accurate threading of HB brand pipe fittings needs no rework on them at the site & are quickly assembled on to the pipes, valves & cocks etc., resulting in considrable saving of time and labour, The perfect alignment of threads HB brand pipe fittings connect the pipes at the required angles of 90° or 180° , thus making piping systems free from any additional strain. it also ensure correctflow of water, liquids, oils, steam, gases etc.
HB brand pipe fittings are given zinc coating by hot dip galvanizing technique, The resultant uniform and thick coating of zinc provides extra protection against environmental corrosion in abnormal conditions. Hence they need no additional protective coating of paints etc.


HB brand pipe fittings have very wide scope of applications & are regularly used on water, oil, steam, air and gas piping system such as :

  • Sanitary and Air conditioning Installations in residential as well as commercial buildings.
  • Erection & Maintenance of Equipment & Pipes for fluids
  • Recycling & Cooling Systems
  • Oil Systems
  • Hydraulic & Pneumatic Circuits
  • Stationery Equipment
  • Fire Prevention Systems
  • Thermal & Refrigeration Equipments & several other similar Industrial Piping Systems
  • Urban and village Water Supply Schemes
  • Domestic Gas & Bio Gas Supply Projects etc.