Pipeline Elbow

Elbows are categorized based on various design features as below:

• Long Radius (LR) Elbows – radius is 1.5 times the pipe diameter
• Short Radius (SR) Elbows – radius is 1.0 times the pipe diameter
• 90 Degree Elbow – where change in direction required is 90°
• 45 Degree Elbow – where change in direction required is 45°

90 degree Elbow Pipe

A 90 degree elbow is also called a “90 bend” or “90 ell”. It is a fitting which is bent in such a way to produce 90 degree change in the direction of flow in the pipe. It used to change the direction in piping and is also sometimes called a “quarter bend”. A 90 degree elbow attaches readily to plastic, copper, cast iron, steel and lead. It can also attach to rubber with stainless steel clamps. It is available in many materials like silicone, rubber compounds, galvanized steel, etc. The main application of an elbow (90 degree) is to connect hoses to valves, water pressure pumps, and deck drains. These elbows can be made from tough nylon material or NPT thread.

45 Degree Elbow Pipe

A 45 degree elbow is also called a “45 bend” or “45 ell”. It is commonly used in water supply facilities, food industrial pipeline networks, chemical industrial pipeline networks, electronic industrial pipeline networks, air conditioning facility pipeline, agriculture and garden production transporting system, pipeline network for solar energy facility, etc.

Most elbows are available in short radius or long radius variants. The short radius elbows have a center-to-end distance equal to the Nominal Pipe Size (NPS) in inches, while the long radius is 1.5 times the NPS in inches. Short elbows are widely available, and are typically used in pressurized systems.

Elbow Pipe having a lot of usage. One of the elbow usage in a pipe line is for determining the rate of flowing the pipe

INTRODUCTION THE USE OF AN ELBOW IN A PIPE LINE FOR DETERMINING THE RATE OF FLOWING THE PIPE

1. Object and Scope of Investigation.-The tests herein reporter were made for the purpose of obtaining information concerning the feasibility of using an elbow in a pipe line as a means of determiningthe flow of a fluid through the pipe, by measuring the difference between the pressures of the fluid on the inside and outside curves of theelbow, respectively, as indicated in Fig. 1. Some of the desirable characteristics of an elbow used as a flow meter are low initial cost, smallcost of upkeep, and no additional resistance to flow due to the elbowbeing converted into a meter.

There are very few published data’-9* available concerning elbowsused as flow meters, especially data concerning the ordinary commercial type of elbow.

The tests reported in this bulletin were made on threaded andflanged elbows of long and short radii, ranging in diameter from oneinch to twenty-four inches. Sixteen different elbows were tested innearly forty different positions and locations in various pipe lines. Allthe elbows tested were 90-deg. bends; typical elbows are shown inFig. 2. Water was the only fluid used in the tests of the elbow metersherein reported.

2. Acknowledgments.-The investigation reported in this bulletin was carried out in the Hydraulics Laboratory of the University ofIllinois as part of the work of the Engineering Experiment Station,of which DEAN M. L. ENGER is the director, and of the Department ofTheoretical and Applied Mechanics, of which PROF. F. B. SEELY isthe head.The tests on the 24-in. elbows were made by MR. E. C. CHAMBERLIN, JR., a senior student at the University of Illinois, in satisfyingthe requirement for a thesis for the degree of Bachelor of Science.

Reference :

Lanford, Wallace M. 1936. The Use Of An Elbow In A Pipe Line Fordetermining The Rate Of Flowin The Pipe. University Of Illinois Bulletin.