How Do I Properly Route a Hose in a Semiconductor Sub-Fab?

BETH NIESER:
Hello and welcome to Ask Swagelok. I'm Beth Nieser, and I'm here today at the Swagelok Hose Building with Margaret Brennan and Doug Nordstrom, who are our host experts for the semiconductor space. And today, we're really here to talk about the importance of properly routing hose in a semifab. So, Margaret and Doug, can you just start by talking about proper hose routing? Why is that so critical?

MARGARET BRENNAN:
Routing is extremely critical for hose applications. I'll focus on the application that connects support equipment down in the subfab to tools up in the clean room. We've seen fabs transition to flux lines in these applications just because it saves so much time and labor during maintenance and tool installation. Routing it specifically is important because it affects the performance and the life cycle of the hose. So, things like overbending to get through tight spaces can kink a hose and affect its performance, and same with bending too soon at an end connection. It can sever the layers and impact the performance of the hose. And then also, if you have extreme temperatures running through the hose, that can affect the spatial needs or surfaces that come in contact with hoses as well. And we need to keep in mind, in a clean room and in a subfab, space is really at a premium. So, it's very difficult to find the right routing for these hoses and avoid the problems that Margaret had mentioned.

DOUG NORDSTROM:
Yeah, so spacing’s really important, especially when it comes to extreme temperature applications. In a fab, you'll typically have extremely cold water that can run through these hoses. When they're in contact with each other or with other surfaces, cold spots can form. The same goes for the hot side—extremely hot temperatures running through these hoses can create hotspots. With cold applications, specifically in subfabs, that can cause condensation and icing to form, which leads to downtime and performance issues. Customers really like to avoid that. In a subfab, there's not a lot of space, so hoses often get routed up against each other, causing these problems. We've worked with some customers to create physical spacers so hoses cannot touch each other, avoiding hot spots and cold spots.

MARGARET BRENNAN:
Of course every hose is intended to be bent so it’s routed from one spot to another. The issue with bending a hose is not to surpass the minimum bend radius. Every hose has a minimum bend radius, which is the point where it no longer elastically deforms. Beyond that, it plastically deforms, representing a damaged hose that will no longer perform as intended or contain the same amount of pressure. When insulation is applied, the minimum bend radius remains the same, but the insulation stretches on the outside and compresses on the inside, which affects its performance. Therefore, we try to maintain three times the minimum bend radius for insulated hoses compared to non-insulated hoses. For example, a hose with a two-inch minimum bend radius should have about a six-inch bend radius when insulated.

DOUG NORDSTROM:
Insulation becomes necessary in fab processes requiring heating or cooling at the tool. Temperature-regulating fluid comes from chillers, heat exchangers, or other support equipment in the subfab. Without insulation, heat can be lost along the hose, and if the outside temperature drops below the dew point, condensation can form, causing potential shutdowns. Insulated hoses prevent the fluid temperature from dropping below the dew point. Standard insulation works down to about -30 °C, but for lower temperatures, vacuum-layered hoses are used. These hoses have a vacuum layer around the inner hose, eliminating convection heat transfer and providing insulation down to cryogenic temperatures like -200 °C. This represents the wave of the future in hose routing and insulation.

BETH NIESER:
Great. Thank you for all that information, and thank you for joining us for Ask Swagelok.