Observe the following guidelines when brazing a pressure control with a copper tube fitting:
Important:
- Overheating the copper tube or control body during installation can cause failure of the P-Series Control. Do not exceed 135°C (275°F) where the copper tube meets the control body.
- Make sure the copper pipe or fixture you are brazing to, receives all of the heat. The copper tube should be heated only by conduction. Failure to do so can damage the pressure control.
Figure 1. Brazing P-Series Controls
Observe the following brazing guidelines:
- The copper tube fitting on all P-Series controls is CDA122 or equivalent copper.
- Silver based (AWS Bag) braze alloy is recommended. Flux is not required.
- A single-flame torch can be used to make a braze joint; however, a multi-tip touch is recommended. This type heats more quickly and uniformly than a single flame.
- Make sure to heat the copper fixture with the outer flame envelope. Hold the touch tip away from the copper fixture so that the inner flame does not touch it. Do not apply the flame directly to the P-Series copper tube.
- Make sure to keep the torch moving to avoid localized overheating.
- Wrap the control end of the copper tube with a quenching cloth for added protection of the P-Series control body
- Brazing of copper to copper joint can typically be accomplished in less than 15 seconds. Applying a heat sink may be required to protect the control body from excessive heat.
Important: Check system operation. Attach a reliable set of gauges to the controlled equipment and operate the equipment at least three cycles at the pressures necessary to verify control setpoints and proper control operation.