hydraulic cathead spec.pdf

7/23/2019 Hydraulic Cathead Spec.pdf

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YM-16 HYDRAULIC CATHEAD

OPERATION MANUALYM-16-SM

Standard ：

Q/320623AD04-2002

API Spec 8A



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CONTENTS

I. Introduction -------------------------------------------------------------------- 1

II. Technical parameters -------------------------------------------------------- 1

III. Working principle and construction --------------------------------------- 1

IV. Operation instructions -------------------------------------------------------- 4



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I. Introduction

Hydraulic cathead is used to loosen or tighten joint of drill strings in offshore and land

drilling. It works with manual tong to perform tightening joints or loosening joints of

large-size drill string (drill pipe, drill collar and casing). Output torque is adjustable.

Torque to tighten or loosen joints can be increased precisely, stably and continuously. If

spinning wrench is also available, then mechanized operation for the whole process of

making-up and breaking-out of drill strings is realized, which can greatly reduce labor

force and secure safety of rig crewmen, and pick up drilling speed and lower drilling cost.

This cathead features simple structure, and easy to handle and repair. Supporting

method is available for user to choose. (Refer to Figure 1).

II. Technical Parameters

1. Rated working pressure 16Mpa （2321 psi）

2. Rated flow 120L/min (31.7 gpm)

3. Rope pull rating 160kN (18 US ton)

4. Normal rope stroke 1620mm (63.78 in)

5. Applicable pipes: to handle tubing, drill pipe, drill collar and casing, applied with tubing

tong, B-type manual tong, casing tong.

6. Refer to Table 1 for wire rope pull under different pressure.

7. Overall dimensions 1932mm×270mm×650mm (46.1X10.6X25.6 in)

8. Weight 420kg (926 lb)

III. Working Principle and Construction

1. Working Principle

YM-16 hydraulic cathead involves hydraulic power unit (to order additionally), control box

(to order additionally) and cathead. Wire rope is hitched to the rear handle of manual

tong. Pressure oil from hydraulic power unit will drive piston rod of cathead cylinder to

move upward and downward. Through movable pulley and fixed pulley, wire rope will pull

manual tong to back turn a certain angle, which helps manual tong finish screwing joints.



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As piston rod retracts, rope withdrawing spring will act to make wire rope restore for the

next operation. The upward and downward movement of piston rod is controlled through

the hand-reversing valve in the control box by drilling worker.

Table I Pressure, Arm, Torque Comparison

Manual tong armlength (in)

Torque(N.m)

Ropepull

SystemPressure (kN)(MPa)

44

(1117.6mm)

48

1219.2mm)

50

(1270mm)

54

(1371.6mm)

20 192 214560 234080 243840 263340

18 176 196640 214560 223520 241390

16 160 178820 195040 203200 219460

15.5 158 177020 193120 201170 217250

15 155 173440 189220 197100 212870

14.5 152 169220 185280 193040 208480

14 149 166240 181410 188980 204100

13.5 144 160960 175570 182880 197500

13 139 155570 169710 176870 190930

12.5 134 150240 163860 176890 184340

12 128 143040 156050 162560 175570

10 105 118020 128740 134110 114830

9 99.2 110860 120940 125980 136060

8 92.8 103710 113140 117860 127280

6 76.8 85820 93630 97540 105340

5 64 71520 78020 81280 87780

3 41.6 46560 50720 52830 57060



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2. Hydraulic Principle See Figure 2

3. Construct ion

(1)Cathead Mounting Drawing

(2)Cylinder Parts Drawing (Figure 3)

(3)Control Box（Figure 4）



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VI. Operation Instructions

1. Mount cathead

1.1 Place selection

The mounting location depends on actual situation. It is recommended to locate thecathead at both sides in front of rig hoist. See Fig.6. The wire rope to pull manual tong

should be at same line with its back supporting center, and minimum space from cathead

to manual tong when start to pull it should be 3m.

1.2 Support and mount mode

Normally, it depends on actual situation to decide which mode.

Piston rod stroke of the cathead is 810 mm, so when adopting piston upward mode, it is

necessary to remain necessary space over the drill platform for extending of the piston

rod. And remain necessary space under the drill platform if adopting piston downward

mode. Drill a φ340 hole on the drill platform to extend the piston rod.

1.3 Fix the supports and mount the cathead.

Cathead is a kind of large power device. It is very important that supporting components

(support seat, pull rod seat and fixed pillar) should be welded by a qualified welder and

strictly complying with technical requirements. Secure support seat 10-15 mm away from

φ340 hole edge.

1.4 Connection between control box and catheadConnect cathead cylinder hoses with A and B ports in control box. Pressure port to A port

and return port to B port. Then connect respectively P, O and drain ports in control box

with pressure port, return port and drain port of power unit

1.5 Assemble rope fittings

1.5.1 Slip stop ring and spring around wire rope, then make the end of rope to be a loop

or clamp with a rope clip to be loop and take it to connect with rear handle of manual

tong. See Fig. 6.

1.5.2 As the hydraulic cylinder is at a full retraction and manual tong at the start-pull

position, pull tight the other end of the rope and secure nowhere slack. Insert the wedge

and pull the rope end with hand as tight as possible to make the wedge enter into the

hole.

1.5.3 Clamp the manual tong on the string, or fix manual tong rear with wire rope. Drive

piston rod to extend out and cause the wedge further tight. If the length of the rope is

inappropriate, knock out the wedge and cut the redundant part.

1.5.4 Push the spring towards guard plate, compress it 150mm towards cylinder and

tighten the clip. (Fig.5)



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1.6 Mounting of control box and power unit

Mount the control box vertically on a rigid member around driller’s console.

Power unit can be placed in any position within 10 meters away from control box. Or

connect to the power source of 16MPa within 10 meters. Pressure hose joint of ourcompany is M30*1.5 for your choice.

2. Operation

2.1 Start hydraulic power. According to the needed torque and the manual tong arm

length, consult Table 1 to choose the corresponding work pressure, and to reset the relief

valve and adjust pressure to needed reading.

2.2 Operate hand-reversing valve of control box to make piston rod extend and pull

manual tong. Retract it after finishing work.

2.3 Torque for each screwing can be show from pressure gauge in control box. But for

precise readings, wire rope should be at 90°against manual tong after piston rod

extended. So, precise readings can be reached only after several relocating.

2.4 Maybe air will remain in the valves and hoses after the cathead’s first assembly in

factory. Operate hand-reversing valve and make piston rod extend and retract

repeatedly for several times, and air will exhaust from the system.

3. Points for attention

3.1 When piston comes to the stroke end, should operate hand-reversing valve to stop

supplying oil.

3.2 Refer to Table 1, wire rope pull should be compatible to manual tong load. Pull over

load is strictly forbidden, as to avoid accident.

3.3 When the cathead is working, operator should be away wire rope, avoid accidents

caused by broken rope.3.4. If wire rope is serious worn due to long-term use, replace the rope timely.

4. Maintenance

4.1 Retract the piston rod into cylinder liner after each work, to prevent corrosion of

exposed parts and seals. Check around piston rod to see if oil leaks. If any, replace the

seals and repair the part causing leaking.

4.2 Regularly coat return-spring for wire rope with anti-corrosive oil and check wire ropefor wend, corrosion, wear, broken or serious kinking. If any, replace right way.



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4.3 Check regularly pressure hose and joints for leaking and broken. Repair and replace

if necessary.

4.4 Inject grease into the grease fittings in shafts of fixed and movable pulleys once

every shift.

To 16MPa pressure source

1. YK-100 shock-proof gauge

2. 34SM-B20H-T hand-reversing valve

3. YM-16 cathead cylinder

Figure 2 Hydraulic Princip le



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To drain hose of power unit

Oil Line Illustration



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Figure 4. Control Box



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Figure 7. Installation of YM-16 Hydraulic Cathead

hydraulic cathead spec.pdf

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