High Integrity Jointing, Quick and Easy
Solvent welding is an easy system which produces a permanent joint of power identical to, or exceeding, the pipe itself.
No specific equipment, tools or hot works permits are necessary.
Limescale and Corrosion Resistant
Limescale and Corrosion can be a troublesome problem for any metal-based pipework system.
The smooth bore lining used by Pieces prevents limescale build up during the life of the system, sustaining constant flow rates.
In addition, Pieces pipework is exceptionally corrosion resistant with a full range of common chemicals which means no expensive system replacement and less maintenance fees.
PVC-U Product Information
Size Ranges from ½” – 12”
Temperature Ranges 0⁰ to + 60⁰
Pressure Rating up to Class E
Compact and simple to fit
Limescale and corrosion resistant
Fully solvent welded system
Excellent chemical resistance properties
The calculation of pressure drop in fittings is more complex but calculations can be made for equivalent lengths of straight pipe using the formula A= B x C where:
A = equivalent pipe length (metres)
B = fittings constant (see table below
C = fitting internal diameter (mm)
To calculate the total pressure drop in the system, the equivalent straight pipe lengths for fittings is then added to the total straight pipe length to obtain the total drop.
90⁰ elbow 0.03
90⁰ tee – straight through 0.01
90⁰ tee – side branch 0.06
90⁰ bend 0.01
45⁰ elbow 0.01
45⁰ bend 0.01
Reducing bush (per size reduction) 0.01
Butterfly valves 0.13
Diaphragm valves 0.23
Check valves 0.05
The values are included as a guide to aid calculation of overall system performance and should not be used in isolation.
Pressure drop due to friction in pipes conveying water can be determined using the Flow Nomogram on page ? NO CLUE HOW TO DO THIS? SORRY
The pressure drop at a given flow rate can be determined as follows:
Systems mounted above ground ought to be designed such that there are enough modifications to accommodate growth or contraction.
The support technique shown below guarantees the pipework is able to move pivotally without twisting.
Make full use of the pipe pliability whilst ensuring the clips are not direct to variation in direction.
Catering for Pipe Movement
Frameworks introduced above ground ought to be outlined to guarantee that there are adequate changes in heading to suit extension and contraction.
The back strategy portrayed afterward will guarantee that the pipework can pivotally without twisting.
If adequate changes in course are not accessible inside the plan of the framework, elective strategies of catering for pipe development can be considered such as extension loops or adaptable rubber elbows.
Pipe Supports and Clips
Pipe bolsters and clips ought to give sidelong restriction and permit free, unhindered, hub pipe development. Standard ‘drop rods’ may not give adequate sidelong limitation and the pipe may begin to twist.
Where the substance have a particular gravity more noteworthy than 1 the separate must be diminished by partitioning the suggested middle separate by the particular gravity.
For vertical channels, bolster centres by be expanded by 50%.
The prescribed distance between underpins and channels filled with water is given within the table shown below.
PVC-U Support Distances
Proposals covering fundamental prerequisites for installations underneath ground may be abridged as follows:
Commonly trenches ought to not be less than a metre profound. Trenches ought to be straight sided, approximately 300mm more extensive than the pipe distance across to permit appropriate solidification of pressing materials. Trench bottoms need to be as level as possible.
Ensure all flotsam and jetsam, rubble and sharp-edged items are cleared away.
On the other hand shingle/grit can be laid approximately 100mm profound on the floor of the trench. Sand may be utilized but underground water is obligated to wash away leaving the pipe unsupported.
Pipes may be jointed above ground but it is imperative they not be moved for at least 2hours before being moved into place.
Once pipes are in correct position they need to be consealed with shingle/grit to a depth of 100mm over the crown of the pipe. The shingle/grit must be amplified sideways to both trench dividers and requires compacting, ideally this had best be done before testing is carried out leaving the joints uncovered.
Before the pipes are re-covered check area thoroughly for risk of rubble, sharp-edged items getting into the trench.
Pressure testing may now be done and when complete will require back filling, cover the pipe joints with shingle/grit.
Below shows an example of the guidance’s given above.
Example to be inserted here?
Technical Information – How To……
Instructions for Jointing
The dissolvable cement works by chemically softening the exterior of the pipe and the interior of the fitting. Joint astuteness is enormously decreased in case these surfaces are not completely spotless and correctly made ready.
Do NOT apply near exposed flame.
Do NOT smoke anywhere in the area using.
Do NOT joint in wet or rain conditions.
Do NOT apply in small compact spaces.
Do NOT use soiled brushes or cloths.
Do NOT use same brushes for multiple cements.
Do NOT water down or thin solvent cement. See the instructions on the tin.
To reach the correct speed of implementation on sizes 5”/140mm and over the cement should be applied to both pipe and fitting at the same time by two people.
Up to 2½” 75mm
3″ – 4″ 90mm – 125mm
5″ & 6″ 140mm & 160mm
8″ 200mm & 225mm
10″ & 12″ 250mm & 315mm
1 hr / bar
1 hr/ bar
1½ hrs / bar
2 hrs / bar
30 hrs minimum
* The drying period must never be less than 1 hr
A demonstration of the number of joints to be made per litre of cement is shown below:
Size Joints per Litre PVC-U
16 – 32 3/8 – 1 300
40 – 63 1¼ – 2 120
75 – 110 2½ – 4 50
125 – 140 5 15
160 – 225 6 – 8 8
250 – 315 10 – 12 3
The following testing method is recommended to be completed once the suitable minimum drying
time has been allowed for the joints.
The pipes should be placed into sections ready for testing.
Fill each section with cold water ensuring there are no air pockets. Do not pressurise yet.
Carefully check for any leaks. If no leaks present make sure you check for and eliminate any
remaining air. The pressure may now be increased up to 3 bar but NO further at this moment.
Allow at least 10 minutes before checking for any pressure break down and repairing any leaks if
required. If the pressure remains continuous then slowly increase the hydrostatic pressure to
1½ times the minimal operating pressure.
Leave the pressurised pipe section no more than 1 hour and the pressure should remain the same.