Design and Development of an Attachment for a Drainage Cleaner

The essential part of running sewer jetters on a truck is identifying beforehand what type of sewer lines lie underneath and how much pressure they can withstand. As sewers are constructed of anything from concrete to steel, a hasty consideration could cause a lot of damage. To maintain the municipal sewers clean, municipalities require powerful vacuum and septic trucks with additional equipments. Cleaning of the drainage system is done by suction mechanism and jet spray mechanism. Apart from jetter, the most important tools are high quality nozzles, proficient of handling anything in the sewer lines. Nozzles are the fundamental part of any high pressure jetting unit. Changing the nozzle can change the function of an entire unit. Different types of nozzles used for drainage cleaning are regular dome nozzle, closed nozzle, rotating nozzle, rocket nozzle and sand nozzle. Regular nozzles are used for initial penetration of 3‟‟-10‟‟ sewer lines. Closed nozzles are used as rear facing jets. Rocket nozzles are used for cleaning heavily compacted debris whereas sand nozzles are used to clear out heavy sand build up. Each time the nozzle is changed according to the time of blockage. In this paper the nozzle implemented is a fast, efficient penetrating nozzle along with a cutter which can clear out total blockage, hard scale deposit along with the root vegetation.

The jetting suction machine is directly placed above the manhole and nozzle is inserted into a manhole. The engine generates the power which then goes to the gear box. The function of gearbox is to reduce speed of output shaft thereby increasing the torque. With the help of Power Transmission Shaft (PTO), power from engine is given to three components, compressor, jetting box and differential. The power from differential is used to drive wheels of the truck and compressor further increases the pressure. Here we are mainly concerned with the jetting box. From the jetting box water goes to the inlet filter and further to the high pressure plunger pump. Further a valve is used to regulate the fluid flow. Lastly, water comes out from the nozzle and the drainage pipes are cleaned.

• Commensurate the exit and atmospheric pressure as closely as desired.

• Reduce jet noise and Infrared Radiation if desired.

• Allow for cooling of walls if necessary.

• Expedite the flow to high velocity with minimum total pressure loss.

• Allow for thrust reversing if desired.

1 Material: Cast Iron SAE30 Material: Cast Iron SAE30 Outer Diameter: 60mm 2 Outer diameter :40mm Outer diameter :40mm Inner Diameter: 40mm 3 Inner diameter:30mm Inner diameter:30mm Width : 14mm 4 Hole diameter:2mm Hole diameter:4mm 5 Pressure:130bar Pressure:130bar 6 No of jet:5 No of jet:4 7 Total length : 70mm Total length: 40mm

Assume FOS=5 Cast Iron µ=0.27 hence Brittle So using Lame‟s Equation:Cast Iron SAE-20 Sut =140

σt = == 20 N/mm2

t=9.79mm10mm Cast Iron SAE-30 Sut =271

σt = == 54.2 N/mm2

t=4.15mm5mm Cast Iron SAE-50 Sut =350

σt = == 70 N/mm2

t=3.10mm3mm Assume FOS=2.5 Cast Steel µ=0.29 Ductile an close ends

Equation: Cast Steel IS-CS-65 Sut =650

σ = == 260 N/mm2

t=0.67mm Cast Steel IS-CS-85 Sut =850

σ = == 340 N/mm2

t=0.50mm Cast Steel IS-CS-125 Sut =1250

σt = == 500 N/mm2

t=0.34mm Birne‟s Equation cannot be used because it is used when both ends are open.

Therefore t=5mm Do =30+10=40mm P=130 bar=13MPa Di =30mm Do=40mm Fs =5 Bearings Do =40mm, So standard Bearing Therefore, Di =40mm

Do=60mm

Width=14 Design of Cylinder: =1099.55mm2 =8.34N/mm2 Design of Collar:

F=9.18KN

σpermissible =54N/mm2 Area= Hence, t=2mm Moment=9.18*15 =137.7 KNmm Mb=137.7KNmm Y=2.5m Putting all the values we get, Hence the design is safe.

The cutter is used to cut the concrete waste, twisted roots of trees and other firm blockages found in the drainage system makes it useful for penetrating various supple and firm blockages in the sewer lines. Hence the time required for changing the nozzle for different types of blockages is reduced.

[1] D. K. Stephens, ”Fluid medium propelled and rotated apparatus for cleaning the inside of pipes”, US Patent November 27 ,1951 [2] John A. Kirschke, “Sewer cleaning chemical dispensing nozzles”, US Patent April 18,1972 [3] L. Allen Sinor, “Rotary drag bit with enhanced hydraulic and stabilization characteristics”, US Patent October 16, 2001 [4] Sadek Ben Lamin, Cody Graham, “Reverse nozzle drill bit”, US Patent June 17, 2010 [5] B D Shiwalkar, “Design data of machine element” Reprint Edition January 2013 [6] Web Article “Drainage Chamber” Available on : https://www.google.co.in/?gfe_rd=cr&ei=VmcKWMqlHInT8gfqiYGwBQ#q=inspection+chamber+definition

Department of Mechanical Engineering, YCCE, Nagpur