Cooling is the heartbeat of a data center. When a water or glycol line weeps at a hose end or a fitting, somebody gets a call at 2 a.m. After 20 years in the instrumentation valve and fitting business, I've learned that the parts you pick for those small cooling hookups matter as much as the big pipe. Here's what facility techs, mechanical contractors and buyers should know about DK-LOK General Purpose Hose and the fittings and valves that go with it.
What DK-LOK General Purpose Hose Is Built For
DK-LOK General Purpose Hose is used for water and glycol in data centers. DK-Lok recommends it for water, glycol antifreeze solutions, petroleum-based hydraulic oils, engine lubricating oils and air. Per DK-Lok, it's rated for a working pressure of 300 PSI and comes in sizes from 1/4" to 3/4". The black cover meets flame resistance acceptance designation MSHA 2G.
That makes it a good fit for the low-pressure side of a cooling system: return lines, drain and fill hookups, equipment connections and other low-pressure lines where you want a flexible run instead of rigid tube.
Know Where It Doesn't Belong
Every hose has limits, and I'd rather you hear them from me than find them the hard way. DK-Lok states that this style of hose and coupling is not recommended for pressure surge or critical applications, such as permanent piping in residential or commercial buildings. So use it for the hookups and low-pressure lines it was made for, and keep the main loop on hard pipe or tubing per your engineer's design. If a line sees surges or sits above 300 PSI, call us and we'll help you pick a different hose.
Fittings and Valves That Match
A hose is only as good as what it connects to. DK-Lok fittings and valves, like the ones A-Best Industrial Inc. Fittings, Valves, and Tubing supplies, are also used on water and glycol lines in data centers. A common setup is a DK-Lok hose adapter or push-on hose fitting at the hose, a DK-Lok tube fitting at the tube, and a quarter-turn ball valve so you can isolate a branch without draining the loop. Browse our ball and plug valves and compression tube fittings.
Already Have Swagelok or Parker on Site?
You don't have to tear anything out to add DK-Lok. DK-Lok tube fittings are 100% interchangeable and intermixable with Swagelok and Parker A-Lok for like size and material, properly assembled per the DK-Lok catalog. In ASTM F1387 testing witnessed by TÜV Rheinland, 14 combinations of intermixed DK-Lok and Swagelok nuts, ferrules and bodies passed 100% of the testing, with "No failure observed." DK-Lok also confirms it in its Parker A-Lok interchangeability letter.
Install It Right the First Time
- Cut hose square and push it fully onto the fitting barb. Don't lube it with anything the fitting maker doesn't allow.
- Route hose without kinks, twists or sharp bends, and keep it off hot surfaces and sharp edges.
- On the tube side, cut square with a RIDGID tube cutter made for stainless steel, using the GRIP-IT TOOL to keep the tube from spinning in your hand, then deburr with a deburring tool. Check each tube fitting with a gap inspection gauge. All of these are on our tools page.
Leak Test Before You Walk Away
Once the line is pressurized per site procedure, apply Gator Leak Detector all the way around each joint you touched and watch for bubbles or foam. On male connectors and other NPT-to-tube fittings, check the pipe-thread joint as well as the tube nut, since the NPT side is often skipped. If something leaks, isolate and depressurize before putting a wrench on it. Never tighten a fitting under pressure.
Let Us Help With Your Cooling Lines
A-Best Industrial Inc. Fittings, Valves, and Tubing is an authorized DK-Lok distributor in San Pedro, serving California and supporting customers nationwide. We also build hose assemblies while you wait; see our hose assemblies page. Call 310-833-3353 or email sales@abesttube.com. We're open Monday–Friday, 8:00 AM–5:00 PM Pacific, with after-hours emergency service.
Swagelok and Parker A-Lok are trademarks of their respective owners.