China HDPE Socket Fusion Elbow Manufacturers Factory Suppliers

The HDPE socket fusion Elbows are heat fused. The sequence below is the standard procedure for the HDPE socket fusion Elbow; the welding machine manual takes precedence wherever the two differ.

Most joint failures trace back to preparation rather than to the fusion cycle, so the preparation steps carry as much weight as the timed ones.

Before you start

Prepare the pipe before the HDPE socket fusion Elbow joint is opened: these are the checks that decide whether the fusion cycle will be worth running.

• Cut the pipe square and remove the burrs., Scrape the oxidation layer off the fusion zone over the full socket depth., Mark the insertion depth on the pipe with a marker., Keep the pipe ends and the units dry and clean. and Check that the marking matches the pipe SDR.

The scrape is the step most often skipped when installing the HDPE socket fusion Elbow. PE oxidises in daylight, and a joint fused through an oxide layer looks sound and still fails under sustained pressure.

Fusion procedure

1. Clamp the pipe in the welding machine.
2. Face both ends until they are parallel and clean.
3. Match the fusion parameters to the dn size and the SDR.
4. Bring the faces to temperature and hold the specified heating time.
5. Remove the heater and bring the joint together inside the changeover time.
6. Hold under pressure for the full cooling time before moving the pipe.

Changeover time is the window between removing the heater and the faces meeting. It is short by design, so everything needed for the next step of the HDPE socket fusion Elbow joint should be within reach before the heater comes out.

Inspection after fusion

On a HDPE socket fusion Elbow joint, check that the insertion marks are still visible at the socket edge and that the bead is continuous and even all the way round. A bead that is thin on one side means the faces were not parallel.

Common defects and causes

These are the failures that recur on hdpe socket fusion elbow installations across the dn20 to dn63 range:

• Cold joint: heating time too short, or changeover time exceeded., Brittle bead: material overheated or contaminated., Offset joint: pipe not clamped square in the machine., Insufficient insertion: depth mark not checked before cooling. and Contaminated fusion zone: scraping skipped or done with a dirty blade.

Related pages

Other pages in the HDPE socket fusion Elbow section, each covering a different angle of the same product family:

• socket fusion 45deg Elbow
• socket fusion Elbow
• socket fusion Elbow Bend