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EF TIPS TO SAVE TIME, MONEY AND HASSLES ON ANY JOB

No-one wants to re-do welds so the best way to save time, money and hassles is to ensure each and every weld is done according to best practice.  The key to good electrofusion welding is contained in the POP001 guidelines for electrofusion installation.

POP001 was put together by PIPA, the Plastics Industry Pipe Association of Australia to detail the best practice processes and parameters for electrofusion welding. Following these steps will help ensure quality, long-lasting and reliable pipe connections, helping you be a better installer and achieve more reliable, leak-free EF welds.

This quick install video shows how the steps outlined in POP001 apply in the field.

see the best practice method to install a 125mm electrofusion coupler

PLASSON has developed the SmartFuse system to help make electrofusion welding simplier. All SmartFuse fittings have built-in resistors that automatically load the correct weld parameters for the fitting into PLASSON SmartFuse electrofusion weld machines.

Welding is made even easier thanks to the SmartFuse app.  It not only guides and prompts installers to complete all of the best practice steps in POP001, the SmartFuse app records this information and the weld record either on USB or in the cloud.

It is important to know and understand all the steps outlined in POP 001 as omitting steps or failing to complete processes adequately can undermine weld quality and lead to failed pipelines.

The processes outlined in POP001 are known as best-practice.  It is crucial to always follow best-practice as failure to do so can open operators up to claims of negligence and compromise insurance cover.

For a full copy of POP001, click here…

EF WELDING: HOW PIPE OVALITY PREVENTS GOOD WELDS

The non-brittle and flexible characteristics of polyethylene make it ideal for many pressure and non-pressure applications. Those useful characteristics also mean PE pipe can alter shape. Ovality generally known as ‘out of roundness’ is one of the most common issues found in PE pipe. One of the best tips to ensure a quality electrofusion weld is to ensure that polyethylene pipe is not out-of-round before attempting the electrofusion process.

To determine if out-of-round conditions exists measure the pipe diameter in numerous directions across the pipe end with a tape measure. If the measurements exceed the maximum tolerance, a re-rounding clamp or device must be used to bring the pipe back to a round condition.

HOW DOES POLYETHYLENE PIPE BECOME OUT-OF-ROUND?

MANUFACTURING
Installers need to confirm that polyethylene pipe matches all dimensional requirements for the job and the fitting being installed and that the pipe does not exceed the allowed ovality. If ovality is greater than allowed you must take steps to re-round the pipe.

STORAGE
Polyethylene pipe that is warehoused for a period of time or stacked on top of each other can experience ovality issues (more pronounced with large diameter pipe).

TIME
Large Diameter Polyethylene pipe will tend to relax a little during storage due to a combination of its weight and its natural flexibility.

INSTALLATION
Mechanical forces experienced during some trenchless installation techniques such as Pipe Bursting or Directional Drilling can temporarily leave the polyethylene pipe elongated and out-of-round.

PREVIOUS INSTALLATION
Polyethylene pipe that has been underground for awhile is subjected to earth loads. These earth loads can cause the pipe to sag and/or become out-of-round.

WHY IT IS KEY TO ADDRESS PIPE OVALITY FOR ELECTROFUSION INSTALLATIONS

One of the most critical functions of the electrofusion process is to seal the gap between the pipe and the fitting and to build up interfacial pressures for the fusion process to take place. If this gap is not sealed and interfacial pressures cannot build up, there is no way for the electrofusion joint to effectively achieve the high quality fusion it was designed for.

If a pipe is out-of-round the initial concern is that the surface area of the pipe may not adequately come in contact with the fusion zone of the electrofusion fitting. This could result in the electrofusion fittings cold zones, which are designed to contain the material generated in the melt pool, allowing the molten material to escape out of the fusion area without producing any melt penetration. This is a key concern when installing tapping and branch saddles since they do not fully encircle the pipe like an electrofusion coupling.

HOW TO CORRECT OUT-OF-ROUND PIPE

First, determine if out-of-round conditions exists. This can be done visually for extreme cases or by measuring the pipe diameter in numerous directions across the pipe end with a tape measure. If the measurements exceed the maximum tolerance, a re-rounding clamp or device must be used to bring the pipe back to a round condition.

The following table shows the approved dimensions for PE100 pipe:

The PLASSON range includes high quality tools to prepare pipe correctly for electrofusion, inlcuding re-rounding clamps.

Click here to see PLASSON’s tooling range….

THE BENEFITS OF  PE PIPELINES

Why PE makes sense and cents!

This industry is pumped full of letters and numbers – like SDR11, HDPE, PE100 and PN16.  There is handy information in those codes that explains exactly what amazing PE can do.  And, when it comes to the different grades of PE, or polyethylene, the magic of what each one delivers is definitely in the detail.

You will find LDPE widely used in plastic packaging or plastic wrap. HDPE is often found in construction and plumbing. And UHMW PE, which is many times stronger than steel, is a high-performance plastic used in bulletproof vests!

The process that makes PE a success was developed in the 1950s by two scientists, Karl Ziegler of Germany and Giulio Natta of Italy. Polyethylene is now one of the most widely produced thermoplastics in the world. It’s light and strong – it’s cheap to transport, easy to handle and safe to store making it a smarter choice than most other materials – especially when it comes to PE pipe.

Drilling down

Polyethylene, like other plastics, starts with the distillation of hydrocarbon fuels into lighter groups called “fractions”.  Some can be combined with other catalysts to produce plastics (typically via polymerization or polycondensation).

Low-Density Polyethylene (LDPE) is a very flexible material with unique flow properties that makes it particularly suitable for shopping bags and other plastic film applications. LDPE has high ductility but low tensile strength, which is why it stretches when strained.

Ultrahigh Molecular Weight Polyethylene (UHMW) is an extremely dense version of polyethylene. It is spun into threads with tensile strengths many times greater than steel and used in bulletproof vests and high-performance equipment.

High-Density Polyethylene (HDPE) is a robust, moderately stiff plastic with a highly crystalline structure. It is used to make all types of strong and tough containers.  The HDPE used to produce corrosion-free, long-life pipelines for water, waste water and gas is called PE100. PLASSON’s range of poly pipe joiners are designed to easily and securely join PE100 pipelines.

PE is classified as a “thermoplastic” (as opposed to “thermoset”), based on the way the plastic responds to heat.

Thermoplastic vs thermoset

One of the benefits of thermoplastics is they can be heated to their melting point, cooled, and reheated again without degradation.  By contrast, thermoset plastics can only be heated once. The first heating causes thermoset materials to set (a bit like a 2-part epoxy), resulting in a chemical change that cannot be reversed.  These properties are what makes PE ideal for gas pipelines joined by electrofusion fittings like the PLASSON SmartFuse range.

the benefits of PLASSON Australia EF branch saddles

PE is rugged, flexible, and durable.  Both the pipe and PE pipe fittings have outstanding chemical and environmental stress crack resistance.  PE pipelines have been successfully used in a wide variety of applications for over 50 years.  Add to that strength and corrosion-resistance, and you get a life-span far in advance of other pipe materials.

TAKE A LOOK AT THE INNOVATIVE RANGE OF PLASSON PE PIPE FITTINGS HERE…

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