You want your heat exchanger to run at optimal efficiency. You also want a low total cost of ownership. But, as you know, you can’t have your cake and eat it too. Instead, you need to strike a balance between efficiency and costs that leads to less downtime, improved overall production, and a more dependable operation in the long term. These seven tips will help you find that balance.
1. Optimize your heat exchanger configuration
Start by checking your heat exchanger’s operating parameters. What fluids are flowing, and at what pressure, temperature and volume? Heat exchangers are often overdesigned, meaning engineers have added 10% to all parameters, and intermediaries add even more on top to ensure it doesn’t underperform. The result is an exchanger with either too many plates or one designed for something different than what it’s being used for. So what can you do to fix this issue and make sure your heat exchanger is adapted to your particular needs?
Contact a vendor that can run calculations to check your heat exchanger’s current operating parameters against its design parameters and see if it’s configured correctly. You can often make changes that result in better heat transfer efficiency and the appropriate pressure drop. A properly configured heat exchanger will remain clean during operations and provide optimal performance for your system. It can also improve the overall performance of the system around it. For example, pumps don’t have to work as hard if the pressure drop is correct.
2. Make sure your exchanger has the right number of plates
Your heat exchanger can have high, low or medium heat transfer plates theta – or a mix of all three. This means you can reconfigure your exchanger by simply changing the number of plates and without touching the piping or its frame. You might think more plates is the way to go because a larger surface area equals better heat transfer – but that’s not always the case. It all comes down to the purpose of your heat exchanger.
Run calculations to determine how many plates your specific heat exchanger needs for optimal heat transfer efficiency and pressure drop, and then add or remove plates accordingly.
3. Choose a vendor with a global supply chain
When you opt for a local, small supplier, you take a significant risk. The vendor might not be around tomorrow, be too busy to help, or not have your exact plates and gaskets in stock. You’ll be at their – and whoever they buy their parts from – mercy.
Instead, choose an established vendor with a global supply chain and ample resources. This way, your vendor will have numerous sources to pull supplies from, ensuring you’ll have the parts you need whenever you need them. A global actor will meet your needs and has the financial muscle and market presence to back it up.
4. Establish a preventive maintenance schedule
Maintenance for heat exchangers requires parts that may not be on the shelf when needed. Hence, if you run your heat exchanger to failure, you might have to scramble to find the parts you require (especially if you depend on a small, local vendor). You also have to deal with the repercussions of a broken heat exchanger. Will you try to get by without it, or will you have to shut down? That’s not a choice you want to make.
Preventive maintenance is about servicing your heat exchanger before it fails, not after. The superior form of preventive maintenance for heat exchangers in the Oil & Gas industry is performance-based maintenance (PbM). PbM is the practice of setting up a maintenance schedule around predefined parameters adhering to the performance of your heat exchanger. Continuously monitor your exchanger’s performance. If heat transfer levels fall outside your preset parameters, that’s when you conduct your maintenance.
Establishing a preventive maintenance schedule should be standard for any company relying on its heat exchangers, as it reduces costs and prevents machine failure and unplanned downtime.
5. Start your heat exchanger gently
Let’s say you’re about to start your inactive heat exchanger, and you fire it right back up to full flow. All the water, gas, or oil that’s pushed through your heat exchanger will cause such an initial shock that it batters its gaskets and plates. Sure, your exchanger can handle the flow of liquids, but when done from 0-100 in one motion, there will be consequences.
Instead, allow your heat exchanger to fill up slowly and then vent the air before turning it to full flow. Be kind to your exchanger, and it will reward you handsomely.
6. Continuously monitor your heat exchanger’s performance, heat transfer and pressure drop
If you don’t track your heat exchanger’s operational parameters, how will you know it’s working like it’s supposed to?
The first step toward monitoring your heat exchangers’ performance, heat transfer and pressure drop is connecting them with temperature and pressure gauges (if you haven’t already). Study the gauges and take a baseline measurement of both the cold and hot sides to create a temperature profile. This lets you clearly see the degradation in its overall performance over time. Continuously observing its performance is also essential for performance-based preventive maintenance, as it allows you to identify abnormal heat transfer levels.
By always being aware of what and how it’s doing, you can prevent both unexpected failures and process upsets. It’s like putting an activity tracker on your heat exchanger to take its pulse. Every heat exchanger needs an activity tracker.
7. Don’t overtighten your heat exchanger
When your heat exchanger is leaking, you can always tighten it down. But tightening it too much will crush its plates and blow its gaskets, and render them useless. And if you try to open a heat exchanger with crushed plates, it will never close again, and you’d have to buy new parts.
That’s why you should only tighten it to the minimum closing dimension. If it’s still leaking after doing so, servicing is your only option.
Do you want to know more about how to optimize your heat exchangers and create an operation that yields the results you want? Read our article on restoring plate heat exchangers to optimal performance.