GATE-CH-1989-9-ii-design-2mark

Match the following: (type of joint with efficiency factor)

• I. Double welded butt joint with full penetration

Answer 1A. 0.65C. 0.7D. 0.5B. 0.55

• II. Single welded butt joint with backing strip

Answer 2A. 0.65C. 0.7D. 0.5B. 0.55

• III. Single welded butt joint without backing strip

Answer 3A. 0.65C. 0.7D. 0.5B. 0.55

• IV. Single full lap joints for circumferential seams only

Answer 4A. 0.65C. 0.7D. 0.5B. 0.55

GATE-CH-1993-16-b-design-2mark

Match the following:

• I. Gasket

Answer 1B. Flange jointsC. FoundationA. External supportD. Base support

• II. Anchor bolts

Answer 2B. Flange jointsC. FoundationA. External supportD. Base support

• III. Skirt

Answer 3B. Flange jointsC. FoundationA. External supportD. Base support

• IV. Guy-wire

Answer 4B. Flange jointsC. FoundationA. External supportD. Base support

GATE-CH-1988-9-b-ii-design-1mark

Two 30 cm diameter steel pipes are connected by:

• threaded joints

• union coupling

• flanges

• sleeves

GATE-CH-1988-9-b-iv-design-1mark

A cylindrical shell \(A\) closed at the ends have been provided with 3 circumferential ring stiffeners. Shell \(B\) is identical to \(A\) but is provided with 6 circumferential stiffeners. Which vessel can withstand more internal pressure?

• \(A\)

• \(B\)

• cannot be predicted

• same pressure in both

GATE-CH-1991-10-i-a-design-1mark

Narrow faced flange is the one where the face contact area lies ------------- the circle enclosed by the the bolt holes.

• inside

• outside

GATE-CH-1998-1-25-design-1mark

For a cylindrical internally pressurized vessel, which of the following closure types would withstand highest pressure if each closure is of the same material and thickness?

• Hemispherical

• Ellipsoidal (2:1)

• Conical

• Flat plate

GATE-CH-1998-2-25-design-2mark

For a cylindrical vessel of moderate height, the weld joint efficiency for joints parallel to the cylinder axis is given as 1.0 while for joints along the girth (circumference) it is given as 0.8. In calculating the shell wall thickness using code formula, for an internally pressurized cylindrical vessel, what value of weld joint efficiency should be used?

• 0.8

• 0.9

• 1.0

• \((0.8)^{0.5}\)

GATE-CH-2001-1-20-design-1mark

A perforated plate has holes of diameter \(d_h\) arranged in a pitch, \(p_h\). Each hole has a tube of i.d., \(d_i\), passing through it. The ligament efficiency is given by

• \(\displaystyle \frac {p_h-d_h}{p_h}\)

• \(\displaystyle \frac {p_h-d_hd_i/2}{p_h}\)

• \(\displaystyle \frac {p_h-d_i}{p_h}\)

• \(\displaystyle \frac {p_h-d_h}{d_h}\)

GATE-CH-2001-1-21-design-1mark

The ends of a cylindrical vessel can be closed by a head, which can be one of the four shapes. For the same thickness, choose the one which can withstand the highest pressure.

• flat plate

• hemispherical

• torispherical

• ellipsoidal

GATE-CH-2007-18-design-1mark

A cylindrical storage tank can have a self supported conical roof,

• if its diameter is less than 20 m

• if its diameter is more than 50 m

• if the thickness of the roof is more than that of the cylindrical shell

• whatever is the diameter

GATE-CH-2010-7-design-1mark

The term ‘knuckle radius’ is associated with

• flat heads

• torispherical heads

• hemispherical heads

• conical heads

GATE-CH-2011-25-design-1mark

In a thin-walled cylindrical vessel of thickness \(t\) with inside radius \(r\), the internal gauge pressure is \(p\). The hoop stress and the longitudinal stress in the shell are \(\sigma _h\) and \(\sigma _l\) respectively. Which ONE of the following statements is TRUE?

• \(\displaystyle \sigma _h=\frac {pr}{t}, \quad \sigma _l=\frac {pr}{4t}\)

• \(\displaystyle \sigma _h=\frac {pr}{4t}, \quad \sigma _l=\frac {pr}{t}\)

• \(\displaystyle \sigma _h=\frac {pr}{2t}, \quad \sigma _l=\frac {pr}{t}\)

• \(\displaystyle \sigma _h=\frac {pr}{t}, \quad \sigma _l=\frac {pr}{2t}\)

GATE-CH-2011-6-design-1mark

Minimum input required to calculate the 'blank diameter' for a torispherical head is

• crown radius

• crown radius, knuckle radius and length of straight flange

• knuckle radius and length of straight flange

• crown radius, and knuckle radius

GATE-CH-2016-21-design-1mark

Standard pipes of different schedule numbers and standard tubes of different BWG numbers are available in the market. For a pipe / tube of a given nominal diameter, which one of the following statements is TRUE?

• Wall thickness increases with increase in both the schedule number and the BWG number

• Wall thickness increases with increase in the schedule number and decreases with increase in the BWG number

• Wall thickness decreases with increase in both the schedule number and the BWG number

• Neither the schedule number, nor the BWG number has any relation to wall thickness

GATE-CH-1992-10-b-design-2mark

For pipe lines handling fluid under pressure, circumferential stiffening rings are used for withstanding higher internal pressure. (True/False)

• True
• False

GATE-CH-1990-19-i-design-6mark

For a 1-1 fixed tubesheet heat exchanger, the following data are given:

Design inside pressure:	shell side	=	\(10^3\) kN/m\(^2\)
	tube side	=	\(2 \times 10^3\) kN/m\(^2\)
Design temperature:	shell side	=	50\(^\circ\)C
	tube side	=	150\(^\circ\)C

Allowable stress at both design temperature is \(1.2 \times 10^5\) kN/m\(^2\). Shell inside diameter = 0.6 m, corrosion allowance for shell and headers = 3 mm and joint efficiency = 1. Find the nearest mm (rounded to the nearest integer):

 (a) the shell thickness
{#1}
(b) the header shell thickness
{#2}

GATE-CH-2002-2-17-design-2mark

A cylindrical pressure vessel of volume \(6\pi \) m³ has to be designed to withstand a maximum internal pressure of 10 atm. The allowable design stress of the material is 125 N/mm² and corrosion allowance is 2 mm. The thickness of the vessel for a length/diameter ratio of 3 will be close to

• 5 mm

• 6 mm

• 8 mm

• 10 mm

GATE-CH-2006-63-design-2mark

Obtain the optimal diameter of a cylindrical storage vessel of volume \(V\). The curved shell costs \(C_s\) (in Rs./m²), and the flat top and bottom plates cost \(C_p\) (in Rs./m²)

• \(\displaystyle D = \frac {C_s}{C_p}\left [\frac {4V}{\pi }\right ]^{1/3}\)

• \(\displaystyle D =\left [\frac {8VC_s}{\pi C_p}\right ]^{1/3}\)

• \(\displaystyle D =\left [\frac {VC_s}{C_p}\right ]^{1/3}\)

• \(\displaystyle D =\left [\frac {4VC_s}{\pi C_p}\right ]^{1/3}\)

GATE-CH-2016-54-design-2mark

A vertical cylindrical tank with a flat roof and bottom is to be constructed for storing 150 m³ of ethylene glycol. The cost of material and fabrication for the tank wall is Rs. 6000 per m² and the same for the roof and the tank bottom are Rs. 2000 and Rs. 4000 per m², respectively. The cost of accessories, piping and instruments can be taken as 10% of the cost of the wall. 10% of the volume of the tank needs to be kept free as vapor space above the liquid storage. What is the optimum diameter (in m) for the tank? __________

• 3.5

• 3.9

• 7.5

• 7.8

GATE-CH-1991-20-i-design-4mark

A spherical storage tank is having an outer diameter of 2 m and a thickness of 5 mm. The tank seams are welded and having joint efficiency of 0.85. The material of construction will be plain carbon steel. The chemical will be stored at the maximum temperature of 298 K. No corrosion problems are expected. What maximum internal pressure (in kN/m\(^2\)) the tank will withstand safely?
Allowable design stress value at working temperature = 118 MN/m\(^2\).

• Answer

GATE-CH-1991-10-i-c-design-1mark

The rigidity of the cylindrical vessel subjected to external pressure may be increased by providing uniformly spaced, internal or external circumferential -------------

• Answer

GATE-CH-1993-15-a-design-2mark

The important stresses induced in the shell of tall vertical vessels are (A) ------------- (B) ------------- (C) ------------- (D) -------------

• Answer

GATE-CH-1993-15-b-design-2mark

The tensile stresses resulting from internal pressure are (i) ------------- expressed as ------------- and (ii) ------------- expressed as -------------

• Answer

GATE-CH-1993-16-a-design-2mark

A cylindrical shell under external pressure tends to ------------- as a result of external pressure. The external pressure at which buckling occurs depends upon ------------- , ------------- and ------------- when the length of the shell is less than the critical length.

• Answer