Soldering Copper Coaxial Cable with Copper Connectors

The objective of this application test is to determine heating times for soldering copper connectors onto a copper coaxial cable. The customer would like to replace hand soldering with soldering irons, with induction soldering. Hand soldering can be labor intensive, and the resulting solder joint is highly dependent on the skill of the operator. Induction soldering allows finite process control, and provides a consistent result.

Equipment

UltraHeat UPT-S2 Power Supply
HS-4 Heat Station

Materials

• Copper Coaxial Cable
• Plated copper connectors
• Copper bullet-shaped internal connector
• Copper pin-shaped internal connector
• Solder wire
• Carbon steel

Key Parameters

Test 1: Soldering Copper Coax Center Conductor to Bullet-Shaped Center Pin

Temperature: ~400F

Power: 1.32 kW

Time: 3 seconds for bullet connector

Frequency: 235 kHz

Key Parameters

Test 2: Soldering Copper Coax center conductor to Needle-Shaped Center Pin

Temperature: ~ 400F

Power: 1.32 kW

Time: 1.5 second for needle connector

Frequency: 235 kHz

Key Parameters

Test 3: Soldering Copper Coax to the End Connector (Bullet-Shaped Center Pin)

Temperature: ~ 400F

Power: 1.8 kW

Time: 30 seconds of heating time, followed by a 10 second cooling cycle

Frequency: 197 kHz

Key Parameters

Test 4: Soldering Copper 
Coax to the End
Connector
(Needle-Shaped Center Pin)

Temperature: ~ 400F

Power: 1.86 kW

Time: 30 seconds of
heating time, followed by a
10 second cooling cycle

Frequency: 199 kHz

Process:

For each type of center pin, the soldering process has two steps.  First, soldering the center pin (bullet-shaped or needle-shaped) to the center conductor of the coaxial cable; and second, soldering the coaxial cable with the pin into the end connector

Tests 1 and 2: Soldering copper coax center conductor to the connector center pin

1. The internal connector pin (needle and bullet followed the same process) were assembled to the coaxial cable center conductor. A solder slug roughly ½ the length of the pin where the wire is to be soldered, was cut and placed in the receiving end of the center pin. The copper conductor of the coax was positioned to rest on the solder slug in the pin with light pressure downward.
2. The assembly was placed into a two-turn induction coil, and power was turned on.
3. As the solder melted, the copper conductor of the coax seated into the center pin. The assembly was held still for several more seconds as the solder cooled. Note: it is important to keep the solder joint still until it has cooled. If movement occurs, a “cold” solder joint can result.

Tests 3 and 4: Soldering copper screw-type end connector to the Center Pin 

1. Solder wire was wound around the corrugated flutes of the coax. The coax with solder was placed into the end connector.
2. The assembly was placed into a u-shaped induction coil, and power was turned on.
3. Heat time – 30 seconds for either assembly followed by a 10 second hold to let the alloy solidify.

Results/Benefits:

The soldering was successful, and confirmed that induction is an excellent alternative to hand soldering.

• Precise control of the time and temperature
• Power on demand with rapid heat cycles
• Repeatable process, not operator dependent
• Safe heating with no open flames
• Energy efficient heating

Pictures

Components for the Bullet End Assembly

Components for the Needle End Assembly

Completed Solder Joints - Bullet End and Needle End to the Coax Center Conductor

Test 3: Solder is would around the corrugated coax.

Test 3: Assembled prior to solder cycle.

Finished assembly.

Videos

Test 1

Test 2

Test 3

Test 4

Ultraflex Power Technologies provides Induction Heating Solutions for your heating challenges. 

Contact us today about your heating application!

Melting Platinum with the UltraMelt 5P

The purpose of the application test was melting platinum, and to determine what quantities will melt effectively in the UltraMelt 5P.  

Due to its properties and high melting temperature, Platinum is a challenging metal to melt. The UltraMelt 5P is the ideal equipment for this task.

EquipmentUltraMelt 5P

Materials
• Scrap Platinum
• Crucible for melting
• A lid for the crucible
• Tongs
• Pipettes (for taking a sample in video 2)

Key Parameters of Test 1:
Melting Platinum – 250g of Scrap
Temperature: over 1768C
Power: 3.9 – 4.8 kW (power varied during the melting process)
Time: 4 minutes, 35 seconds
Frequency: 91 kHz

Key Parameters of Test 2:
Melting Platinum – 250g of solidTemperature: over 1768C
Power: 3.1 – 4 kW (power varied during the melting process)
Time: 4 minutes, 10 seconds
Frequency: 94 kHz

Process:

1. Platinum was added to the ceramic crucible.
2. UltraMelt 5P was turned on.
3. The engineer tapped lightly on the crucible to settle the material, and help the heat distribute throughout the material. The tapping also helped to loosen pieces of the scrap platinum to drop into the molten platinum.
4. A cap or lid was placed on the crucible to minimize heat loss. In this case, another crucible was used as the cap.
5. As power was applied, the platinum began to melt and flow to the bottom of the crucible.
6. There were some small differences in the process between test 1 and test 2, as noted in the videos.
   • For Test 1, with the Scrap Platinum, after 2 minutes 37 seconds of heating, the platinum is molten at the bottom of the crucible; After 4 minutes 35 seconds of operation, the platinum is completely molten, and the UltraMelt 5P is turned off.
   • For Test 2, with the solid piece of platinum, after 4 minutes 10 seconds of operation, the platinum was completely molten. A pipette was lowered into the molten platinum to take a sample.  The UltraMelt 5P was turned off.
7. Since we did not have a mold to pour the molten platinum into, we cooled the platinum in the crucible.  The crucible was turned upside down during cooling, to allow the platinum to eventually fall out of the crucible.

Results/Benefits:

Different quantities of platinum were tested in increments of 50g, from 50g to 250g.  The tests results indicated that successful platinum melting was optimized at approximately 250g.

Pictures

During the test, the engineer taps periodically on the crucible to help in the heating process.  The engineer is wearing welding goggles, due to the brightness of the molten platinum. 

Here we see the second crucible used as a lid for the primary crucible.

During test 2, a pipette was lowered into the molten platinum to take a sample.

When taking the sample, there was a brief flare.

A view of the still hot platinum in the bottom of the crucible.

After cooling, the platinum releases from the crucible.

The final melted piece of platinum after cooling.

The pipette with the cooled sample.

Videos

Test 1: Melting 250g of Scrap Platinum

Test 2: Melting a solid sample of platinum, and taking a sample

Ultraflex Power Technologies provides Induction Heating Solutions for your heating challenges. 

Contact us today about your heating application!