Through Hole PCB Assembly

Through Hole PCB Assembly

At Sierra Assembly, we offer a complete range of through-hole manufacturing capabilities including auto-insertion, wave, and selective soldering. More to this, we also offer automated component insertion of both radial and axial components.  

Through-hole PCB assembly is referred to as a mounting scheme, in which electronic components are inserted through holes drilled into PCBs and soldered to pads on the opposite side either by using automated insertion mount machine or manual assembly. At Sierra Assembly, we offer a complete range of through-hole manufacturing capabilities including auto-insertion, wave, and selective soldering. More to this, we also offer automated component insertion of both radial and axial components.

Manual and Automated Through-hole Assembly Offered by Sierra Assembly

At Sierra Assembly, we use both manual and automated through-hole techniques for placing radial and axial components. When it comes to small-volume production, we usually prefer automated through-hole PCB technique. This helps reduce material handling and labor. Our manual technique can handle complex through-hole assembly challenges. This technique is designed to minimize operator movement as well as product travel. Documentation along with in-process checks ensure the complete and accurate population of the assembly. Wave-soldering is utilized for both through-hole and surface mount components. However, we prefer to use it for through-hole components. Moreover, in mixed technology PCBs are both reflowed and wave-soldered.

Steps Involved in Manual and Automated Assembly

  • Step 1: Once the printed circuit board (PCBs) is soldered, it is cleaned by our team to remove all the flux residue. Different techniques are utilized to remove the flux residue. These are usually a combination of agitation, cleaning agents, and heat.
  • Step 2: Once the cleaning of the circuit board is done, it is sent for a detailed inspection, where our skilled experts check for accurate component placement.
  • Step 3: Quality of the assembled circuit boards is checked using different inspection tools and techniques, which mainly include automated optical inspection, X-ray inspection and more.
  • Step 4: After successful quality testing, the printed circuit boards are delivered to the customers over a short period of time.

Our Through-hole Assembly Capabilities

At Sierra Assembly, we offer the following through-hole assembly services:
  • Manual Insertion of Components
  • Hand Soldering
  • Radial and Automate Insertion
  • Double Wave Flow Solder
  • Legacy Assembly or RoHS Soldering using tin-lead solder
  • Make use of low and high melting point solder
  • Inspection and functional testing
  • Conformal Coating
  • Encapsulation of PCB
  • Device Programming

Advantages of Through-hole PCB Assemblies

A through-hole assembly offers certain benefits, some of them are as follows:
  1. Easier Prototyping: Through-hole has become an industry standard because of its reliability. More to being reliable, through-hole components can easily be exchanged.
  2. Strong Physical Connections: Unlike SMT components, through-hole components can withstand mechanical or environmental stress as they run through the board rather than being secured to the circuit board surface.
  3. Superior Power Handling Capability: Through-hole soldering forms a superior bond between the circuit board and components. This makes the board perfect for larger components that will undergo high voltage and high current.
  4. Greater Heat Tolerance: Owing to the high heat tolerance capability, through-hole PCB assembly is preferred for many products in aerospace and military sectors.

FAQs on Through Hole Assembly

We, at Sierra Assembly, strive to answer all the questions we get from our clients. Here are some frequently asked questions on through hole assembly we have answered.

  1. What is through hole assembly?
    This is one of the widely used component mounting processes used in the PCB manufacturing segment. The components are mounted through leads in this process, and the circuits are completed. This is one of the processes for component mounting which Sierra Assembly offers. In this process, we drill holes wherein the components are placed through soldering. We perform wave or manual soldering depending on the requirement such as the number of components, design complexity, and so on.
  2. What are the through hole assembly components known as?
    Through hole assembly components are radial lead and axial components.
  3. What does THT PCBA stand for?
    This stands for Through Hole Technology Printed Circuit Board Assembly.
  4. What are the capabilities you offer for through hole assembly?
    We offer RoHS-compliant and quick turn PCB assemblies. We stick to our delivery schedules as decided with the client, and this is done without compromising on the quality. Here are some of the capabilities we offer for our through hole PCB assemblies.
  • Full or partial turnkey solutions
  • Manual as well as automated component mounting
  • ROHS compliance
  • Stringent testing procedures
  • Hand soldering
  • Device encapsulation
  • Using low and high melting point solder
  • Conformal coating
  • Device programming
  1. What are the benefits of through-hole assembly?
    Through hole is often compared with surface mount technology, wherein the latter is newer and perceived to be better. However, both these methods have their own strengths. Through hole certainly has its own benefits, and is especially useful for high voltage applications. Here are some other benefits.
    • This is a reliable component mounting method and can withstand a high amount of mechanical stress, high temperatures, and environmental parameters.
    • Through hole soldering enables a strong bond between the components and the circuit.
    • Here, the leads are pre-drilled in a crisscross manner through which leads bent at right angles are threaded and soldered in the right place. This increases mechanical strength.
    • It increases the suitability of the board for large components with high voltage as well as current requirements.
    • Sierra Assembly complies with the required industry standards and offers both manual and automated assemblies.
  1. What are the testing profiles you use for through hole assemblies?
    At Sierra Assembly, we have stringent protocols in place for through hole assembly testing. We perform thermal profiling, flying probe testing, ICT testing, and functional testing. By using all these techniques, we assure reliability and accuracy. This also ensures reduced production losses, extended operational life of equipment, streamlined processes, environment friendliness through reduced wastage, and most of all the safety of our employees.
  2. Which are the common application areas for through hole PCB assemblies?

We commonly use them for applications such as semiconductors, transformers, connectors, and so on. The fact that through-hole assembled boards are high temperature resistant makes them applicable in mission critical areas in defense and aerospace.

  1. What is the turnaround time you offer?

We offer complete assemblies within three weeks in case of standard applications. This may vary depending upon the complexity. But we deliver on time as decided with the client.

  1. What is the price range of through hole PCB assemblies you offer?

The costing depends on many factors such as part numbers, materials, used, design, and client requirements among others. However, we can offer you a quick quote once you share your requirements with us.

For over several years, from prototyping to production to repair, Sierra Assembly Technology has been offering mixed, surface mount, and through-hole PCB assembly services. We assure that you need not worry about the quality as our diligent staff follows all the inspection steps for through-hole PCB assembly.

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