To ensure the connection quality of electrofusion fittings, the following measures can be taken:

Firstly, ensure the cleanliness and dryness of the pipe and fitting surfaces before connection. Any dirt, moisture, or debris can affect the welding quality. For instance, if there is oil or grease on the surfaces, it can prevent proper fusion.

Secondly, use the correct type and model of electrofusion welding machine that is compatible with the fittings. The welding parameters should be set accurately according to the manufacturer's instructions. A wrong setting could lead to incomplete fusion or overheating.

Thirdly, perform a visual inspection of the fittings and pipes for any damage, deformities, or irregularities. Defective components should not be used. Say, if there are cracks on the fitting, it must be replaced.

During the welding process, monitor the temperature and time strictly. The welding time should not be too short or too long. An insufficient welding time may result in a weak connection, while an excessive one might damage the material.

After the welding is completed, allow the connection to cool down naturally without any disturbance. Rapid cooling can affect the strength of the joint.

Carry out a pressure test or leakage test on the connected pipeline to check for any leaks or weaknesses. This test should be conducted at the specified pressure and for the required duration.

Regularly calibrate and maintain the welding equipment to ensure its accuracy and reliability. Faulty equipment can lead to inconsistent welding results.

Make sure the operators are well-trained and experienced in electrofusion welding techniques. They should understand the process and be able to handle any issues that arise during the operation.

Adhere strictly to the manufacturer's guidelines and industry standards for the connection process. Any deviation from the recommended procedures can compromise the connection quality.

For example, in a large-scale plumbing project, all these steps are crucial to ensure that the electrofusion connections of the PE pipes and fittings remain leak-free and reliable over the long term. Another example could be in a gas pipeline installation, where even a minor flaw in the connection could lead to serious safety hazards, emphasizing the importance of ensuring connection quality.