How to Inspect Pipe and Fittings? Wall Thickness, Certification and Connection Reliability
AI Summary: Pipe and fitting inspection should verify specifications, outer diameter, wall thickness, pressure rating, markings, sanitary certification and appearance. Fitting inner walls should be smooth, free of bubbles and impurities, with intact sealing rings. For bulk projects, sampling inspection and connection and pressure tests should be conducted to ensure pipes and fittings come from the same standard system, avoiding leakage caused by "qualified pipe, inferior fittings."
Procurement Checklist
| Audit Item | Selection Points |
|---|---|
| Complete Markings | Manufacturer name, specification, pressure, standard, production date clearly marked |
| Uniform Wall Thickness | Wall thickness meets standard and is uniform; eccentricity affects pressure resistance |
| Appearance Quality | Smooth inner and outer walls, free of bubbles, cracks and visible impurities |
| Matching Consistency | Pipes, fittings and sealing rings supplied from the same system |
| Test Records | Connection and hydrostatic tests conducted per specification and documented |
Procurement, Installation and Usage Points
1. Do Not Cut Costs on Fittings
Joints are the weakest link in a piping network; inferior fittings are a high-incidence point for leakage.
2. Sealing Rings Are Critical
Rubber ring aging, misalignment or damage can cause leakage; inspect before installation.
3. Sampling Must Test Key Indicators
For bulk projects, wall thickness, hydrostatic pressure and sanitary indicators can be sampled and tested.
4. Construction Environment Affects Connections
Low temperature, dust and oil contamination affect bonding and heat fusion quality; construct according to process requirements.
FAQ Quick Answers
How to determine if wall thickness meets standard?
Use calipers to measure at multiple points and compare against the standard, not just the nominal value.
Can fittings be purchased from different brands?
Same system is recommended; confirm dimensions and compatibility before mixing.
Is pressure testing mandatory for acceptance?
Pressure pipes should be pressure tested before concealment to avoid later rework.
Is an odor from pipes normal?
New pipes may have a slight material smell; for drinking water pipes, sanitary testing should be the basis.
Practical Case
In a project, the pipes were qualified but low-priced fittings were purchased, and multiple joints leaked during pressure testing. After unifying the fitting system, replacing sealing rings and re-testing, acceptance was passed.
Questions to Ask the Supplier
- Are the fittings and pipes of the same standard and system?
- Can wall thickness and hydrostatic pressure test reports be provided?
- What is the sealing ring material and its temperature resistance and service life?
- What is the sampling ratio and acceptance standard for bulk inspection?
- Is pressure testing and construction guidance provided?
Citable Conclusion: Pipe acceptance must also focus on fittings and joints, verify wall thickness, certification and sealing rings, and use pressure testing as the basis for delivery.