About steel pipe flanges
About steel pipe fittings
Service and Applications
Industry Knowledge


Do you know anything about reducers?

Do you know anything about reducers? Reducers in Process PipingA reducer is a kind of pipe fitting used in process piping that reduces the pipe size from a larger bore toa smaller bore (inner diameter).A reducer allows for a change in pipe size to meet hydraulic flow requirements of the system, or to adapt to existing piping of a different size. The length of the reduction is usually equal to the average of the larger and smaller pipe diameters.There are two main types of reducer:Concentric reducersEccentric reducersReducers are usually concentric but eccentric reducers are used when required to maintain the same top-or bottom-of-pipe level.Concentric ReducerIn Concentric Reducer the reduction of the pipe size is achieved by decreasing the diameter of the fitting at a constant rate over a specified length, maintaining symmetry around the fitting. Concentric Reducersare used to join pipe or tube sections of different diameters on the same axis. They provide an in-line conical transition between pressurized pipes of differing diameters. Thus, concentric reducers connect pipes of unequal size but have a common centerline. The same fitting can be used in reverse as an concentric expander.Eccentric ReducerIn Eccentric Reducer the reduction of the pipe size is achieved by decreasing the diameter of the fitting at a constant rate over a specified length, maintaining one side of the fitting horizontally. An eccentric pipe reducer fitting is manufactured with the smaller outlet off center to the larger end, which allows it to align with only one side of the inlet. The same fitting can be used in reverse as an eccentric expander.Uses of Concentric and Eccentric ReducersIn horizontal liquid piping, eccentric reducer must be installed with flat side up so that it can prevent trapping air in the piping system. As an exception, same is flat side down in piperack where same Bottom of Pipe (BOP) has to be maintained. Other exception is with control valves. A eccentric reducer with flat side down will give a more constant flow through the control valve rather than a concentric reducer or eccentric reducer with flat side up, which will give your more flow disruption and will cause problems with your control valve.In horizontal gas / vapor / steam piping, eccentric reducer must be installed with flat side down which allows condensed water or fluid to drain at low points.

Product information about elbows

Product information about elbows Steel pipe elbow (sometimes also refereed as bends) is a key part in a pressure piping system used to change the fluid flow direction. It is used to connect two pipes with same or different nominal diameters, and to make the pipe and thus the fluid direction turn to a certain direction of 45 degree or 90 degree. This change in fluid flow direction adds pressure losses to the system due to impact, friction and re-acceleration.Classification of Steel Pipe ElbowsSteel pipe elbows can be classified through following various parameters,Direction AngleLength and RadiusConnection with PipeMaterial of ConstructionTypes of Elbows based on Direction AngleAccording to fluid flow direction of the pipes, elbows can be divided into different degrees, such as 45 degree, 90 degree, 180 degree, which are most common elbows. Also there are 60 degree and 120 degree elbows for some special pipelines. This degree is just an representation of the angle by which the fluid flow is going to change after flowing through the said elbow. Types of Elbows based on Length and RadiusElbows are split into two groups which define the distance over which the flowing fluid change direction; the center line of one end to the opposite face. This is known as the “Center to Face” distance and is equivalent to the radius through which the elbow is bent.If the radius is the same as pipe diameter (Center-to-Face dimension of 1.0 X diameter ), it called Short Radius Elbow (SR elbow) used normally for low pressure and low speed pipelines or in tight areas where clearance is the main issue. If the radius is larger than pipe diameter (Center-to-Face dimension of 1.5 X diameter) then we call it a Long Radius Elbow (LR Elbow) used for high pressure and high flow rate pipelines.

Do you know what are the sides of the flange?

Do you know what are the sides of the flange? Raised Face Flange (RF)The Raised Face flange is the most common type used in process plant applications, and is easily to identify. It is referred to as a raised face because the gasket surfaces are raised above the bolting circle face. This face type allows the use of a wide combination of gasket designs, including flat ring sheet types and metallic composites such as spiral wound and double jacketed types. The purpose of a RF flange is to concentrate more pressure on a smaller gasket area and thereby increase the pressure containment capability of the joint. For 150# and 300# flanges, the raised face is of 1.6 mm (1/16 inch) and is included in the thickness specified. For higher rating, the flange thickness does not include the raised face thickness.  Flat Face Flange (FF)The Flat Face flange has a gasket surface in the same plane as the bolting circle face. Applications using flat face flanges are frequently those in which the mating flange or flanged fitting is made from a casting. Flat face flanges are never to be bolted to a raised face flange. Ring Type Joint (RTJ) The Ring Type Joint flanges are typically used in high pressure (Class 600 and higher rating) and/or high temperature services above 800°F (427°C). They have grooves cut into their faces which seats ring gaskets. The flanges seal when tightened bolts compress the gasket between the flanges into the grooves, deforming the gasket to make intimate contact inside the grooves, creating a metal to metal seal. An RTJ flange may have a raised face with a ring groove machined into it. 

Which flanges are we often used?

Which flanges are we often used? Slip On FlangeThe Slip On type flanges are attached by two fillet welds, inside as well as outside the flange. The calculated strength from a Slip On flange under internal pressure is of the order of two-thirds that of Welding Neck flanges, and their life under fatigue is about one-third that of the latter. Normally, these flanges are of forged construction and are provided with hub. Sometimes, these flanges are fabricated from plates and are not provided with the hub.The disadvantage of the flange is that a combination of flange and elbow or flange and tee is not possible because named fittings have not a straight end that complete slid in the Slip On flange. Socket Weld FlangeThe Socket weld flanges are attached by only one fillet weld, only on outside, and are not recommended for severe services. These are used for small-bore lines only. Their static strength is equal to Slip On flanges, but their fatigue strength is 50% greater than double-welded Slip On flanges. The thickness of connecting pipe should be specified for this type of flanges to ensure proper bore dimension.In socket weld flange, before welding, a space must be created between flange or fitting and pipe. ASME B31.1 Preparation for Welding (E) Socket Weld Assembly says:In assembly of the joint before welding, the pipe or tube shall be inserted into the socket to the maximum depth and then withdrawn approximately 1/16″ (1.6 mm) away from contact between the end of the pipe and the shoulder of the socket.The purpose for the bottoming clearance in a Socket Weld is usually to reduce the residual stress at the root of the weld that could occur during solidification of the weld metal. The image shows you the X measure for the expansion gap.The disadvantage of socket weld flange is right the gap, that must be made. By corrosive products, and mainly in stainless steel pipe systems, the crack between pipe and flange can give corrosion problems. In some processes this flange is also not allowed. Threaded Flange The Screwed or Threaded flanges are used on pipe lines where welding cannot be carried out. A threaded flange or fitting is not suitable for a pipe system with thin wall thickness, because cutting thread on a pipe is not possible.Thus,thicker wall thickness must be chosen.ASME B31.3 Piping Guide says:Where steel pipe is threaded and used for steam service above 250 psi or for water service above 100 psi with water temperatures above 220°F, the pipe shall be seamless and have a thickness at least equal to schedule 80 of ASME B36.10.Socket welding and threaded flanges are not recommended for service above 250°C and below -45 C. Weld Neck FlangeWelding Neck Flanges are easy to recognize as the long tapered hub, that goes gradually over to the wall thickness from a pipe or fitting. The long tapered hub provides an important reinforcement for use in several applications involving high pressure, sub-zero and / or elevated temperatures. The smooth transition from flange thickness to pipe or fitting wall thickness effected by the taper is extremely beneficial, under conditions of repeated bending, caused by line expansion or other variable forces.These flanges are bored to match the inside diameter of the mating pipe or fitting so there will be no restriction of product flow. This prevents turbulence at the joint and reduces erosion. They also provide excellent stress distribution through the tapered hub.The Weld neck flanges are attached by butt-welding to the pipes. These are used mainly for critical services where all the weld joints need radiographic inspection. While specifying these flanges, the thickness of the welding end also should be specified along with flange specification. Blind FlangeBlind Flanges are manufactured without a bore and used to blank off the ends of piping, Valves and pressure vessel openings.From the standpoint of internal pressure and bolt loading, blind flanges, particularly in the larger sizes, are the most highly stressed flange types.However, most of these stresses are bending types near the center, and since there is no standard inside diameter, these flanges are suitable for higher pressure temperature applications.

Which Certificate does JS FITTINGS have?

Which Certificates does JS FITTINGS have? Owner HEBEI JINSHENG PIPE FITTING MANUFACTURING CO., LTD Brand JS FITTINGS Certificate GB/T 19001-2016 / ISO 9001:2015 Valid scope seamless steel pipe fittings, welded steel pipe fittings, forged pipe flanges, forged steel pipe fittings Owner HEBEI JINSHENG PIPE FITTING MANUFACTURING CO., LTD Brand JS FITTINGS Certificate GOST-R Valid scope GOST 17375 pipe elbows LR, GOST 17376 pipe tees, GOST 17378 pipe reducers, GOST 17379 pipe caps. GOST 3262-75 pipe elbows SR, GOST 33259 pipe flanges, GOST 6533 pipe caps, etc Owner HEBEI JINSHENG PIPE FITTING MANUFACTURING CO., LTD Brand JS FITTINGS Certificate CE certificate, Certificate of compliance Valid Scope EN, BS, ASME, ANSI, DIN seamless pipe fittings, welded pipe fittings, forged flanges