Maximum pressure. Under no condition shall acetylene be generated, piped (except in approved cylinder manifolds) or utilized at a pressure in excess of 15 psig (103 kPa gauge pressure) or 30 psia (206 kPa absolute). The 30 psia (206 kPa absolute) limit is intended to prevent unsafe use of acetylene in pressurized chambers such as caissons, underground excavations or tunnel construction.) This requirement is not intended to apply to storage of acetylene dissolved in a suitable solvent in cylinders manufactured and maintained according to U.S. Department of Transportation requirements, or to acetylene for chemical use. The use of liquid acetylene shall be prohibited.
Cylinders not having fixed hand wheels shall have keys, handles, or nonadjustable wrenches on valve stems while these cylinders are in service. In multiple cylinder installations only one key or handle is required for each manifold.
manifold system 8 0 cracked
Unless connected to a manifold, oxygen from a cylinder shall not be used without first attaching an oxygen regulator to the cylinder valve. Before connecting the regulator to the cylinder valve, the valve shall be opened slightly for an instant and then closed. Always stand to one side of the outlet when opening the cylinder valve.
Fuel-gas shall never be used from cylinders through torches or other devices equipped with shutoff valves without reducing the pressure through a suitable regulator attached to the cylinder valve or manifold.
Where a special wrench is required it shall be left in position on the stem of the valve while the cylinder is in use so that the fuel-gas flow can be quickly turned off in case of emergency. In the case of manifolded or coupled cylinders at least one such wrench shall always be available for immediate use.
Except as provided in paragraph (c)(1)(iii) of this section fuel-gas cylinders connected to one manifold inside a building shall be limited to a total capacity not exceeding 300 pounds (135.9 kg) of liquefied petroleum gas or 3,000 cubic feet (84 m3) of other fuel-gas. More than one such manifold with connected cylinders may be located in the same room provided the manifolds are at least 50 feet (15 m) apart or separated by a noncombustible barrier at least 5 feet (1.5 m) high having a fire-resistance rating of at least one-half hour.
Fuel-gas cylinders connected to one manifold having an aggregate capacity exceeding 300 pounds (135.9 kg) of liquefied petroleum gas or 3,000 cubic feet (84 m3) of other fuel-gas shall be located outdoors, or in a separate building or room constructed in accordance with paragraphs (f)(6)(i)(H) and (f)(6)(i)(I) of this section.
Separate manifold buildings or rooms may also be used for the storage of drums of calcium carbide and cylinders containing fuel gases as provided in paragraph (b)(3) of this section. Such buildings or rooms shall have no open flames for heating or lighting and shall be well-ventilated.
Oxygen manifolds shall not be located in an acetylene generator room. Oxygen manifolds shall be separated from fuel-gas cylinders or combustible materials (especially oil or grease), a minimum distance of 20 feet (6.1 m) or by a noncombustible barrier at least 5 feet (1.5 m) high having a fire-resistance rating of at least one-half hour.
Except as provided in paragraph (c)(2)(iv) of this section, oxygen cylinders connected to one manifold shall be limited to a total gas capacity of 6,000 cubic feet (168 m3). More than one such manifold with connected cylinders may be located in the same room provided the manifolds are at least 50 feet (15 m) apart or separated by a noncombustible barrier at least 5 feet (1.5 m) high having a fire-resistance rating of at least one-half hour.
An oxygen manifold, to which cylinders having an aggregate capacity of more than 6,000 cubic feet (168 m3) of oxygen are connected, should be located outdoors or in a separate noncombustible building. Such a manifold, if located inside a building having other occupancy, shall be located in a separate room of noncombustible construction having a fire-resistance rating of at least one-half hour or in an area with no combustible material within 20 feet (6.1 m) of the manifold.
An oxygen manifold or oxygen bulk supply system which has storage capacity of more than 13,000 cubic feet (364 m3) of oxygen (measured at 14.7 psia (101 kPa) and 70 F (21.1 C)), connected in service or ready for service, or more than 25,000 cubic feet (700 m3) of oxygen (measured at 14.7 psia (101 kPa) and 70 F (21.1 C)), including unconnected reserves on hand at the site, shall comply with the provisions of the Standard for Bulk Oxygen Systems at Consumer Sites, NFPA No. 566-1965.
Hose connections and hose complying with paragraph (e)(5) of this section may be used to connect the outlet of a manifold pressure regulator to piping providing the working pressure of the piping is 250 psi (1.7 MPa) or less and the length of the hose does not exceed 5 feet (1.5 m). Hose shall have a minimum bursting pressure of 1,000 psig (6.8 MPa).
When oxygen is supplied to a service piping system from a low-pressure oxygen manifold without an intervening pressure regulating device, the piping system shall have a minimum design pressure of 250 psig (1.7 MPa). A pressure regulating device shall be used at each station outlet when the connected equipment is for use at pressures less than 250 psig (1.7 MPa).
Gas cocks or valves shall be provided for all buildings at points where they will be readily accessible for shutting off the gas supply to these buildings in any emergency. There shall also be provided a shutoff valve in the discharge line from the generator, gas holder, manifold or other source of supply.
When a part of the generator house is to be used for the storage or manifolding of oxygen cylinders, the space to be so occupied shall be separated from the generator or carbide storage section by partition walls continuous from floor to roof or ceiling, of the type of construction stated in paragraph (f)(6)(i)(H) of this section. Such separation walls shall be without openings and shall be joined to the floor, other walls and ceiling or roof in a manner to effect a permanent gas-tight joint.
The box was built with an 8 way cross manifold where my system has the primary inlet and 5 zones of the possible 7 being used. The valves are glued to a short piece of pipe and then glued to the manifold.
The job entails replacing the manifold, the ball valve, three of the zone valves, two caps, and three couplings. In all, it requires 18 glue joints to rebuild my system. My sprinkler installer says that the job will take him about 2.5 hours including wiring and testing, provided that he has all of the fittings and parts on his truck. If not, he must go back to his shop or supply house, costing another hour. Total down time is half day after arrival. Total cost to the installer in fittings and parts is $39; $85 is my cost. Labor, including drive time is four hours at $95 per hour, which is $465 plus tax for a total of $495.
The latest technology for glued pipe system repairs is ungluing and reusing fittings, replacing only the pipe that is broken. This requires a Pipe Debonder tool that is commercially available. Ungluing the one joint from the manifold to the leaking sprinkler valve requires these steps:
Some exhaust manifolds are designed to store the extreme heat caused by the still-burning exhaust gases leaving the individual cylinders. This helps burn any residual fuel in the exhaust before the gas is sent to the next emission device, the catalytic converter.
If the exhaust manifold gets corroded to the point of cracking, you'll hear a tapping sound. Other possible symptoms include black smoke from the exhaust when you accelerate and a lit check engine light.
No, driving a vehicle with a leak in the exhaust manifold is not recommended. It can ruin fuel mileage, cause you to fail a smog inspection, ruin the catalytic converter and cause damage to the exhaust valves.
Most exhaust manifolds last the lifetime of the engine. But problems do occur, and the likelihood of replacement is based on age rather than mileage. Hot engine temperatures from imbalanced air-fuel ratios will cause leaks in manifolds at any mileage.
Starting your car one morning, you're startled to hear it's as loud as a NASCAR racer. There are some other odd symptoms, too, all pointing to a failed exhaust manifold gasket. Here's what you need to know before getting started.
The exhaust manifold gasket, as with any gasket, acts as a sealing surface sandwiched between two different metal components. The gasket is made of layers of metal or composite materials, and prevents leaks as the two metal surfaces go through countless heating/cooling expansion and contraction cycles over an engine's operational life. During the exhaust stroke, the exhaust valve opens to allow spent gases to exit the combustion chamber through the exhaust port in the cylinder head. The gasket is an airtight seal against the head, so the gasses pass into the exhaust manifold and on to the rest of the exhaust system. The gasket prevents noxious gases and incredibly high temperatures from escaping the engine at the wrong point.
Generally, exhaust manifold gaskets are hardy items, often lasting well over 100,000 miles. A lack of engine maintenance and carbon buildup, however, can cause hot spots in the combustion chambers and exhaust ports. This can cause a gasket to catch fire or expand outward. This is a good reminder to use fuel system cleaners to remove carbon buildup.
Throw away the old gasket. Spray the exhaust manifold with heavy-duty degreaser or brake cleaner. Once it's dry, examine the manifold for any leftover carbon buildup or cracks. Clean if you find carbon and replace if you find cracks.
A staple in the landscape industry under the Pepco brand name, now rebranded as a Jain Octa-Bubbler, this pressure compensating manifold is a popular 8 port solution for many retrofit applications. The Jain Octa Bubbler allows installers to customize flow ports with interchangeable inserts maximizing flow control. For ports not in use the Octa-Bubbler also has Port Plugs available (P/N). 2ff7e9595c
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