Tie-Rod and Pipe Joints

Given:
- A Turnbuckle consisting of: Body (M.S.) – 1 off, Rod A (M.S.) – 1 off, Rod B (M.S.) – 1 off.
- Scale: 1:1
- 55 mm threaded portion of each rod is inserted inside the body.

Concept / Assembly Principle:
A Turnbuckle is a tie-rod joint used to connect two rods under tension. The body is a hexagonal or cylindrical barrel with internal right-hand (RH) thread at one end and left-hand (LH) thread at the other end. Rod A has RH external thread and Rod B has LH external thread. When the body is rotated, both rods are drawn in or pushed out simultaneously.

Steps for Drawing:

Step 1 – Understand the parts:
- Body: Hexagonal barrel with a central hole threaded RH on one side and LH on the other. Note the overall length and outer hexagonal size from the given detail drawing.
- Rod A: Cylindrical rod with RH threaded end (thread length sufficient to insert 55 mm inside body).
- Rod B: Cylindrical rod with LH threaded end (thread length sufficient to insert 55 mm inside body).

Step 2 – Assembly:
- Screw Rod A into the RH threaded end of the body so that 55 mm of its threaded portion lies inside the body.
- Screw Rod B into the LH threaded end of the body so that 55 mm of its threaded portion lies inside the body.
- The two rods project outward from either end of the body.

Step 3 – Draw Front View (Upper Half in Section):
- Draw the overall outline of the assembled turnbuckle as a front view.
- The upper half is shown in section (cutting plane passes through the axis).
- In the sectioned upper half:
- Show the internal threads of the body (represented by thin lines for thread roots and thick lines for thread crests, or by conventional thread representation as per SP:46).
- Show 55 mm of Rod A's threaded shank inside the body on the RH side.
- Show 55 mm of Rod B's threaded shank inside the body on the LH side.
- Apply hatching (section lines at 45°) to the cut surfaces of the body.
- The lower half shows the external hexagonal profile of the body and the external view of the rods.
- Mark the 55 mm insertion depth with a dimension line on each side.

Step 4 – Draw Left Hand Side View:
- Project the left-hand side view from the front view.
- The body appears as a regular hexagon (across flats dimension as given).
- The rod appears as a circle (diameter of rod shank) concentric with the hexagon.
- Show hidden lines if required for the internal bore.

Step 5 – Dimensioning and Labelling:
- Provide overall length of assembly.
- Diameter of rods.
- Across-flats dimension of body.
- Length of body.
- 55 mm threaded insertion length.
- Thread designation (e.g., M20 or as per given detail).
- Write title: TURNBUCKLE — ASSEMBLY, Scale 1:1.

Important Note on dimensions (read from detail drawing Fig. 5.8):
- Overall length of body ≈ as given in detail.
- Rod diameter and thread size as given.
- The total assembled length = Length of body + protruding length of Rod A + protruding length of Rod B (after 55 mm insertion each side).

Result: The assembled front view (upper half in section) clearly shows the internal threaded engagement of 55 mm on each side, and the left-hand side view shows the hexagonal cross-section of the body with the rod circle inside.

Given:
- Parts: (a) Body, (b) Rod-A (LH thread, $\phi$20), (c) Rod-B.
- Scale: 1:1
- 50 mm threaded portion of each rod inserted inside the body.

Concept:
Same as Exercise 1. The body has LH thread on one end (for Rod-A, $\phi$20 LH) and RH thread on the other end (for Rod-B). Rotating the body tightens or loosens the joint.

Assembly Steps:
- Insert Rod-A (LH thread, $\phi$20) into the LH threaded end of the body — 50 mm inside.
- Insert Rod-B (RH thread) into the RH threaded end of the body — 50 mm inside.

Step 1 – Lower Half Sectional Elevation (Front View, lower half in section):
- Draw the complete outline of the assembled turnbuckle in elevation (front view).
- The lower half is cut by a horizontal cutting plane through the axis.
- In the lower half section:
- Show the internal bore of the body with conventional thread representation.
- Show 50 mm of Rod-A threaded shank inside the body (LH side).
- Show 50 mm of Rod-B threaded shank inside the body (RH side).
- Apply 45° hatching to sectioned material (body cross-section).
- The upper half shows the external view: hexagonal flats of body, external profile of rods.

Step 2 – Plan (Top View):
- Project the top view below (or above, as per convention) the elevation.
- Body appears as a hexagon (regular, across-flats as given).
- Rods appear as rectangles (width = rod diameter) projecting from each end of the hexagon.
- Show centre lines.
- Hidden lines for internal bore shown as dashed lines.

Step 3 – Six Important Dimensions to be given:
$$\text{1. Overall length of assembly}$$
$$\text{2. Length of body (barrel)}$$
$$\text{3. Diameter of Rod-A } (\phi 20)$$
$$\text{4. Diameter of Rod-B}$$
$$\text{5. Across-flats dimension of hexagonal body}$$
$$\text{6. Threaded insertion length } = 50 \text{ mm (each side)}$$

Step 4 – Title Block:
- Title: TURNBUCKLE — ASSEMBLY
- Scale: 1:1
- Draw the first-angle or third-angle projection symbol as applicable.

Result: The lower half sectional elevation shows internal thread engagement of 50 mm on each side; the plan shows the hexagonal body with rod projections.

Given:
- Assembled Turnbuckle (Fig. 5.12) is given.
- Disassemble and draw individual parts separately.
- Scale: 1:1
- Maintain the same orientation w.r.t. H.P. and V.P. as in the assembly.

Concept:
Disassembly means drawing each part separately (detail drawing) in the same position/orientation as it appears in the assembly view.

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(a) BODY:

Part description: The body is a hexagonal barrel with a central through-hole. One half has RH internal thread, the other half has LH internal thread. There is a central collar or the hex section runs the full length.

(i) Front View — Upper Half in Section:
- Draw the front view of the body alone (without rods).
- The upper half is sectioned by a horizontal plane through the axis.
- In the upper half (section):
- Show the internal bore diameter.
- Show RH thread on one side and LH thread on the other side (conventional thread representation: thin lines for roots, thick lines for crests, or simplified representation).
- Apply 45° hatching to the cut material.
- The lower half shows the external hexagonal profile.
- Mark: overall length of body, bore diameter, across-flats dimension, thread designation.

(ii) Top View:
- Project the top view from the front view.
- The body appears as a rectangle (length = body length, width = across-flats dimension).
- Show the hexagonal flats as visible lines.
- Show the central bore as hidden (dashed) lines.
- Mark centre lines.

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(b) ROD B:

Part description: Rod B is a cylindrical rod with one end having external thread (RH or LH as applicable) and the other end plain or with a hole/eye for connection.

(i) Front View:
- Draw Rod B in the same orientation as in the assembly (axis horizontal).
- Show the threaded end with conventional thread representation (length of thread as readable from assembly).
- Show the plain shank portion.
- Show the other end (eye/plain end) as applicable.
- Dimension: overall length, shank diameter, thread length, thread designation.

(ii) Left Side View:
- Project the left side view from the front view.
- The rod appears as a circle (diameter = shank diameter $\phi$).
- If the end has a flat or hole, show accordingly.
- Show centre lines.

Result: Four separate views are drawn — Body (front view upper half in section + top view) and Rod B (front view + left side view) — each to scale 1:1 in the same orientation as the assembly.