UPMRC Fitter Maintainer (Civil) Paper with solution -2021

Answer.4. Weight of the machine

The specifications for the size of a lathe include the following items:

1. Bed length:-  Bed length, or working distance between centers, is a fairly straightforward specification. It basically defines the distance between the headstock center and the tailstock center. Note that some lathe manufacturers offer extensions for their beds.

2. The length between centers corresponds to the maximum length of work that can be mounted between lathe centers.

3. The maximum bar diameter. This is the maximum diameter of bar stock (metal bars) that will pass through the hole in the headstock spindle.

Answer.1. Elbow

Explanation

A vice is used for gripping and holding a workpiece in position for carrying out on its various bench working operations.

Fitter Vice include

1. Pipe vice
2. Leg vice
3. Pin vice
4. Bench Vice
5. Hand Vice

Hence Elbow is not a plumbing tool.

Answer.2. 15 Psi

Explanation:-

Acetylene is a flammable, colorless gas with a distinctive odor that is easily detected, even when strongly diluted with air.

Under low pressure .at normal temperature, when free from air, acetylene is a stable compound; however, when it is compressed in an empty container to a pressure greater than 15 psi [103 kPa], it becomes unstable. At 29.4 psi [202.74 kPa] pressure it becomes self-explosive, and only a slight shock is required to cause it to explode even when it is not mixed with air or oxygen. As a general rule. the technician should never allow the acetylene pressure in the welding system to exceed 15 psi [103 kPal].

Answer.1. D = T  − 2d

Explanation:-

Tapping is the operation of cutting internal threads by means of a cutting tool called a tap. When the tap is screwed into the hole it removes metal and cuts internal threads which will fit into external threads of the same size.

For tapping purpose, the hole size to be made through drilling has to be smaller than the tap size. The size of the drill is calculated by using following equation : D = T – 2d

 Where, D = Size of the drill (diameter),

 T = Diameter of the tap

Answer.3. Gas welding torch consists of one more hole which carries the mixture of oxygen and acetylene for cutting action.

Explanation:-

Oxyacetylene Welding Equipment:

Following equipment are used in oxyacetylene welding

Gas cylinders: Two gas cylinders made of steel are used. One is of black color used for oxygen and the other is of maroon or red color used for acetylene.

Pressure gages: Each cylinder consists of two pressure gauges. One pressure gauge shows the pressure of the gas inside the cylinder and the other shows the pressure of gas supplied to the blowpipe.

Pressure regulator: Each cylinder is provided a pressure regulator. The function of the pressure regulator is to control the pressure of the gas supply to blowpipe or to maintain the constant pressure of the gas.

Blowpipe or welding torch: The high-pressure blowpipe consists of two passages: one is for oxygen and the other is for acetylene. Both the gases are mixed in a chamber and then driven out through the orifice of the blowpipe nozzle with the desired velocity. These nozzles are usually known as tips and are made interchangeable so that the same blowpipe can be used for different sizes of tips.

Note: Acetylene cannot be filled alone in a cylinder due to dissociation at high pressure so it is mixed with a small amount of acetone.

Answer.3. To cut an external thread on a pipe

Explanation:-

Pipe Dies:- Dies are used for cutting external threads on circular sections of metal, plastic rod, and pipe. Dies are available in a number of different forms and are held in ‘stocks’ so that they can be rotated around the rod or pipe. The split allows for adjustments to be made to the size or depth of the thread being cut.

Answer.4. 700

Explanation:-

The cutting speed is given as

vc = (π × DC × n)/1000 

Where

DC = Drill Diameter = 1 cm = 10mm

vc = cutting speed =22 per minute

n = Main Axis Spindle Speed 

22 = (3.14 × 10 × n)/1000

n = 22,000/31.4

n = 700.63

n ≅ 700

Answer.4. A modern instrument that incorporated all features of the vernier caliper

Vernier Calipers used for measuring outside dimensions, inside dimensions, and depth measurements, all in one tool. They have a graduated bar with markings like a ruler.

Dial vernier caliper

A dial vernier caliper looks much like a standard vernier caliper and is also graduated in thousandths (0.001) of an inch. The main difference is that instead of a double scale, as on the vernier caliper, the dial vernier has the inches marked only along the main body of the caliper and a dial that indicates thousandths (0.001) of an inch. The range of the dial vernier caliper is usually 6 inches.

Answer.1. Tap

Explanation

The Fitting system type is assigned to connectors used in Pipe Fitting Families, such as tees and elbows. These types of connectors will inherit the flow, direction, and system characteristics of the components they connect to.

Many of the pipe fittings used in hydronic systems are the same as used in domestic water supply systems. They include:

• Couplings: (standard and reducing):
• Elbows: (90° and 45°);
• Street elbows: (90° and 45°);
• Tees: (standard and reducing);
• Threaded adapters: (male and female);
• Unions