11/3/2021 12 Comments Our project includes a warehouse ESFR fire sprinkler system. We specified minimum Schedule 10 for all pipe. The contractor has proposed Schedule 7 for use in the 2-1/2" and 4" diameter pipe. Any pros or cons to using Schedule 7 that you'd recommend from experience? Sent in anonymouslyfor discussion. Click Title to View |Submit Your Question|Subscribe 12 Comments Sidney T Forin 11/3/2021 08:14:25 am Check the levels of MIC in the local city water system, we've replaced a lot of schedule 7 pipe with pin holes in certain areas where the levels of MIC was high. Reply Anthony 11/3/2021 08:16:50 am Its thinner, so obvious downsides from a life span and durability stand point. The benefits come from cost obviously and also its flexibility. The pipe is slightly easier to bend so it can be easier to install under a rolling pitched roof where you're going to let the flexing in the pipe and couplings track the roof pitch rather than swing joints. It can be slightly easier to install which the fitters might appreciate or they might complain that its as wobbly as a pop can, good luck making 'em happy. This is a common practice in warehouse applications and I wouldn't have a problem allowing it as a specifier/engineer as long as the cost savings were passed on to the owner. Appx 20%~30% reduction in pipe cost. Reply David Kendrick 11/3/2021 10:09:34 am This caught my eye. The 20% to 30% number must be from a market different than ours. Schedule 10 to Schedule 7 price comparison rounds to 11%. Since we're discussing thinwall pipe I didn't compare pricing to Schedule 40 or 80. Also NFPA 13 restricts the schedule of pipe that may be bent. Schedule 10 steel pipe and heavier. Unless its listing includes bending. Personally I've only installed Schedule 7 pipe as structure to support my chain link fence. Reply Anthony 11/16/2021 08:35:02 am It was the number thrown around our office when ordering I was never the purchasing agent so I may be off on the cost savings. I'm not talking about bending the pipe, I'm talking about the natural flex in the pipe. Bending involves 'plastic deformation' of the pipe. flex is the elastic bending in the pipe such as a spring would experience. Over a 100' span its not unusual to see the pipe be able to take up a 1'-0 differential in roof elevation especially with the ¼~¾ deg of cheat you can get out of a grooved coupling Dan Wilder 11/3/2021 08:17:01 am Pros Cons Since warehouses tend to be an "install and leave as is", if you can get a majority of the air out to reduce the trapped air/water interface locations there shouldn't be an issue. If this is in an area with "harder" water (I'm in Phoenix, all of our water is considered "hard" due to the chemicals put in to keep it potable) I would stick with Sch 10 at a minimum. Reply Jesse 11/3/2021 08:22:37 am I guess my answer would depend on why Schedule 10 was specified. We find a lot of institutional projects spec Sch. 40, but find that their general spec requirements are often times decades old. When we present them with reasons to use Schedule 10, they often see benefit. In your case I'm curious as to whether Schedule 7 was suggested for cost reasons, or something else. Sch. 7 pipe has a larger inside diameter so it performs a little better hydraulically, but I'm not sure in your case that's why they want it. I'd be curious to know why. My bet would be on material cost. Reply Shawn Hoyer 11/3/2021 09:31:38 am The main issue is corrosion at the peak where there is the water/air interface as Dan had mentioned. Even if the system is designed and installed to help alleviate the trapped air, there will be portions where the air will still be trapped and corrosion will happen. The question is how long before it happens. I would take into consideration the needs of your client and what your relationship is to that client. There are many factors that affect how to best serve each individual. Most of them depend on you understanding their needs. Start with what their intent is with the building. If they are a "short term" owner/developer and would be looking to sell off the building with maximum profits, then go ahead and allow the use of the Schedule 7 pipe assuming their is a cost savings. The issues with pipe corrosion would be the next person's problem. However, if this is a "long term" investment that they intend to hold on to, I would definitely recommend Schedule 10 as a minimum and ensure that the system(s) are designed and installed to alleviate as much trapped air as possible. Neither of which should have a cost impact over what you had specified. You know your client and what's important to them. Base your recommendations on that and make sure you keep the client informed on what they are buying. The last thing you want is to have a client that thought they bought the Cadillac and found out it was a Pinto. Reply Lucas Kirn 11/3/2021 10:00:43 am I echo Shawn’s comment above. It’s important to consider the owner’s plan for the building - short term build and sell or long term hold? Another consideration is what the building is being used for. Is it basic storage of dry goods or is it a production facility or fulfillment center that would be more sensitive to business disruption if the sch 7 pipe begins to experience leaks/failures? Reply Dave 11/3/2021 10:37:24 am Probably not a deciding factor, but don't forget that the lateral sway bracing section of NFPA #13 requires you to comply with the maximum load tables in NFPA #13, or if it is not one of those pipe types (e.g., S40, S10, S5), you must use the values published by the manufacturer. (Some brace calculations software prompts you of this requirement.) Wheatland and Bull Moose for example have pdf maximum load tables for their versions of flow-pipe. Reply Robert Allan Kluck 11/3/2021 02:01:07 pm You don't mention the material (Carbon Steel or SS). If it is Carbon Steel, the risk of MIC might be high, especially if your city water that will fill the system is more chemically active( or if the area is a chemical or salt air environment). If it is stainless steel, then the risk of corrosion goes down substantially. Reply sean 11/5/2021 06:26:53 am I see the most common reason in my area to use schedule 7 is weight. Easier on the field guys to move it around. Reply Alex 11/5/2021 07:15:21 am Hi, Long story short - if you specified schedule 10, go schedule 10. If you do allow the schedule 7, make sure you look for a credit. In my opinion, I would say the minimum should be schedule 10. If you have hard water, you can be looking at pinholes within a few years. BUT, say you are adding a temp system (complete or even just egress) to be removed within a year, then corrosion and pinholes shouldn't be the deciding factor. Thanks, Reply Leave a Reply. | SUBMIT A QUESTION Why Sponsor? ALL-ACCESSGET ALL OUR TOOLS SUBSCRIBESubscribe and learn something new each day: COMMUNITYTop May '24 Contributors SEE LEADERBOARD YOUR POSTSUBMIT A QUESTION PE EXAMGet 100 Days of Free Sample Questions right to you! FILTERSAll ARCHIVESJune 2024 PE PREP SERIESSEE LEADERBOARD RSS Feed |
FAQs
What is schedule 7 pipe? ›
Fayette Pipe's Schedule 7 is produced from high-quality American-made coil and seam welded using Fayette Pipe's high-frequency electric resistance weld (ERW) pipe mill. It conforms to Grade A standards with nominal wall thickness as specified.
What is the best pipe for a fire sprinkler system? ›But when proper precautions are taken, CPVC can be a safe, reliable, lower-cost alternative to metallic pipes for light-hazard occupancies—an option that limits costly corrosion issues. CPVC fire sprinkler pipes and fittings offer easier installation and lower cost compared to metallic options.
What are the disadvantages of a dry pipe sprinkler system? ›There are several disadvantages to using dry pipe sprinkler systems. Due to their added complexity and more stringent installation requirements, they are more expensive and time-consuming to install when compared to a wet pipe sprinkler system.
What is the best material for a sprinkler system? ›Polyethylene pipes are mainly used in sprinkler systems because of their high-pressure rating. The rating system is basically a measurement of pressure-bearing load. Some particular environmental conditions require flexible pipes that can adjust to any changes. For example, in cold climates, the soil becomes frozen.
Can you groove schedule 7 pipe? ›Youngstown Tube manufactures Fire-Flo (schedule 7) pipe in sizes 1 ½" thru 4" using only high quality domestic steel coils. This ensures a uniform superior product for roll grooving, welding or plain end uses.
What size pipe is best for sprinklers? ›Sprinkler pipes typically range in size from 1/2 inch to 6 inches in diameter. The most common sizes used in residential and small commercial irrigation systems are 3/4 inch and 1 inch.
What is the best pipe for outdoor irrigation system? ›Polyethylene (PE) Pipe: PE pipe is highly flexible, making it suitable for various irrigation configurations. It is resistant to corrosion, chemicals, and UV radiation, ensuring longevity and durability.
What schedule pipe is used for fire sprinkler systems? ›ASTM A53 specifies that sprinkler systems must use a minimum of Schedule 40 pipe, but heavier pipes may be used if necessary. ANSI/ASTM Standard A135Resistance value welded pipe is covered by this standard. This manufacturing method allows for thinner line walls while also reducing corrosion.
What is the life expectancy of a dry pipe sprinkler system? ›35 years for a wet system and 25 years for a dry system is a common life expectancy.
What is the main reason for using a dry pipe sprinkler system instead of a wet pipe sprinkler system? ›Dry pipe sprinkler systems are filled with pressurized air or nitrogen instead of water to prevent frozen and burst sprinkler pipes in areas with colder temperatures. The pressurized air in the sprinkler pipes prevents water from entering the pipes.
What psi should a dry sprinkler system be? ›
As noted above, a pressure difference holds dry pipe valves closed — the sprinkler piping generally has a pressure five times higher than the water supply when the valve is shut. A typical pressure on the system side is 40 psi, which must fall to 6 psi to open the dry pipe valve.
What are the two materials most commonly used for pipes in a fire sprinkler system? ›Thus, fire sprinkler system pipe material must be versatile, easy to install, cost-effective, and—above all—reliable to meet the needs of this diverse market. Steel has traditionally been the material of choice for fire sprinklers, although thermoplastic pipes now dominate residential and other light-hazard categories.
How can I make my sprinklers more powerful? ›By checking the pressure regulator, inspecting the sprinkler heads, checking for leaks, doing a pressure test, installing more stations and increasing the water supply line, you can boost water pressure and keep your lawn healthy and green.
What is the simplest and most reliable of all sprinkler systems? ›Wet Pipe Fire Sprinklers are the Most Simplistic & Reliable Life Safety Systems. Wet pipe sprinkler systems are the simplest and most common fire suppression method on the market today. They are comprised of pipes that constantly contain pressurized water.
What does SCH pipe stand for? ›A pipe schedule (SCH) is a measure of a steel pipe's nominal wall thickness. In the past, metal fabricators used three pipe dimensions — standard, extra strong, and double extra strong. Just having these three undetermined dimensions wasn't helpful, though. So today, steel pipes come in 14 different schedules.
What does SCH stand for in piping? ›What is a Pipe Schedule? Pipe schedule (SCH) is how the wall thickness of a pipe is described. It is not an actual measurement, but a guide number based on a wall thickness formula. Two pipes the same diameter may have different schedules, which means they have a different wall thickness.
Why is it called Schedule 40 pipe? ›In the context of Schedule 40 pipes, NPS becomes especially relevant as it is commonly used to categorize and differentiate these pipes based on their nominal sizes. The designation “Schedule 40” refers to the pipe's wall thickness and has a specific range of NPS values.
What is Schedule 10 pipe used for? ›This stainless steel schedule 10S pipes has a wide range of industrial applications and is used in industries like water lines, pulp and paper industry, sea water desalination, oil and gas refineries, heat exchangers, and the petroleum industry more.