Maintenance

Introduction

Introduction

This manual provides the necessary information that is required by site maintenance personnel for the correct disassembly and assembly of the spur gear rotary head.

All information, illustrations, and specifications in this manual are based on the latest information at the time of publication. Product improvement is a continuous goal at Epiroc. Design and specifications are subject to change without notice or obligation of notice.

If any part of this manual cannot be understood, contact your supervisor or local Epiroc distributor.

NOTICE

Component Damage

The use of repair parts other than those included within the Epiroc approved parts list can create hazardous conditions over which Epiroc has no control.

  1. Do not use non-approved repair parts. Epiroc cannot be held responsible for equipment in which non-approved repair parts are installed.

  2. When the life of the equipment is expired, it is recommended that the equipment be disassembled, degreased, and parts be separated by materials so that they can be recycled.

NOTICE

Safety Precautions

Failure to obey the safety instructions and warnings can cause product damage, personal injury, or death.

  1. Safety is always the primary concern for the protection of both personnel and the equipment during assembly and disassembly. All personnel must understand all safety precautions and procedures before doing any maintenance work on the spur gear rotary head.

  2. Safety is an integral part of every individual job responsibility. Every employee must be committed to these beliefs and must work in a manner that demonstrates that commitment.

Design Features

The spur gear rotary head provides the rotation speed and the rotary torque that is necessary for drilling with Epiroc drilling machines. The rotary head is a simple, compact, and efficient unit featuring dual axial piston hydraulic motors mounted at the top of the gear case for easy access. The rotation motors, which are powered by hydraulic oil from the main pumps, drive the spindle through a series of spur gears. Rotation motors are used to rotate the drill bit and to add and remove the drill pipe from the drill string which is connected to the rotary head.

The rotation speed is determined by the output of the main pumps. The output is variable through speed controls on the operator's panel at a maximum working pressure of 345 bar (5,000 psi). There is a motor control valve located on one of the motors on the rotary head, which changes the stroke of the motor producing a wide range of outputs. This arrangement enables the head to provide an option of either high torque [25,761 Nm (19,000 ft-lb @ 95 rpm)] or high speed [170 rpm @ 14,236 Nm (10,500 ft-lb)] or a desired torque and speed range within these parameters.

The internal bearings, pinions, and gears in the rotary head are cooled and lubricated with EP 80W90 gear oil. Approximately 208 liters (55 gallons) of oil are necessary to bring the oil to its correct level in the gear case. Make sure that the oil level is correct using the sight gauge on the front side of the gear case.

A special drill pipe adapter serves as a spindle sub. This sub is screwed tightly into the spindle and held in position by welded locking tabs. When the spindle sub break or the threads become damaged, the sub can be removed, thus eliminating the need for replacement of the more costly spindle.

Bearing Design and Gear Maintenance

NOTE

Use only new bearings. Do not reuse bearings.

NOTE

Refer to Table Rebuild Kit List for item numbers.

Items 6 and 12 are single-row, tapered roller bearings, and are the most widely used throughout the industry. They are especially applicable for carrying radial and axial loads, acting simultaneously when the radial loading is greater than the axial.

Items 8 and 105 are single-row, medium-type, and deep-groove ball bearings. They will sustain radial load and substantial thrust load in either direction, even at high speed. This advantage results from intimate contact between the balls and the deep continuous groove in each ring. For this type of bearing, careful alignment between shaft and housing is essential. These bearings are supplied with two red shields for roller protection from dirt and other contaminates.

Item 9 is a spherical roller bearing with cylindrical bore, narrow width and medium type design. It has excellent radial load carrying capacity due to the number, size and shape of the rollers and the accuracy with which they are guided.

Being inherently self-aligning, angular mis-alignment between the shaft and the housing has no detrimental effect and full bearing capacity is always available for loading. Considerable thrust loading may be carried in either direction.

Recommended Lubrication Oil

EP oils contain additives with the following properties:

  • Increases load-carry properties

  • Highly resistant to oxidation

  • Non-corrosive to metals

  • Highly resistant to foaming

80W140 synthetic gear oil is added at the factory.

Weights and Tolerances

Component and Assembly Weights

Component

Part Weight

Assembly Weight

Spindle

159.7 kg (351.4 lb)

123.2 kg (271 lb)

With bearing 215.1 kg (473.2 lb)

With bearing - 178.5 kg (392.8 lb)

Intermediate gear

68.9 kg (151.6 lb)

With shaft and bearing 109 kg (239.7 lb)

Input pinion

22.2 kg (48.8 lb)

With bearings 30.4 kg (66.8 lb)

Rotary head

1,534.5 kg (3,376 lb)

4,037.3 kg (8,882 lb)

Output gear

176.4 kg (388 lb)

-

NOTE

Tolerances on the Output Gear Tolerances and the Housing Tolerances drawings are in inches.

Output Gear Tolerances
Housing Tolerances

A

Section A-A

B

Section J-J

C

Section A-A

Rotary Head Rebuild Kit

Rotary Head Kit List Reference Drawing
Rotary Head Kit List Reference Drawing (cont.)

A

Section B-B

B

Section F-F

C

Section H-H

D

Section C-C

E

Section A-A

J

Section G-G

Item

Quantity

Description

1

1 EA

Spindle

3

2 EA

Pinion input

6

1 EA

Bearing, pull down

-

1 EA

Cone

-

1 EA

Cup

7

1 EA

CUF

8

2 EA

Bearing, ball

9

4 EA

Bearing, intermediate shaft

-

1 EA

Cone

-

1 EA

Cup

11

1 EA

Seal, oil

12

1 EA

Cone

13

2 EA

Key, intermediate

17

2 EA

Spacer

18

1 EA

Nut, Adjusting

-

1 EA

Lock nut, bearing

19

1 EA

Tongued washer, bearing

22

2 EA

Holder, bearing

24

1 EA

Collar

25

1 EA

Key

26

1 EA

Sleeve, bottom

27

1 EA

Sleeve, wear

28

1 EA

Shield, drip

30

2 EA

Packing, swivel - 30XV

31

1 EA

Bushing, wear

32

2 EA

O- ring

33

2 EA

Seal, oil

34

2 EA

Seal, oil

42

2 EA

Ring

43

1 EA

O-ring

44

1 EA

Ring, lock

47

1 EA

O-ring

48

2 EA

O-ring

49

2 EA

O-ring

59

2 EA

Shim kit

60

2 EA

Nut, elastic lock-3/8-16

94

1 EA

Adhesive

95

1 EA

Component, silicone

98

1 EA

O-ring

99

2 EA

Seal, oil

100

2 EA

Adjusting, bearing

101

2 EA

O-ring

105

2 EA

Bearing, ball

Assembly Checklist

Initial

Date

Step Number

Procedural Steps

3.1 Set-Up and Preparation

1

Correctly mount the housing into the rotary head working stand.

2

Remove the cover. Clean and put it aside.

3

Clean the housing.

4

Reposition the housing.

5

Heat the lower spindle bearing cone.

6

Freeze the upper and the lower bearing cups.

7-8

Make sure that there is no damage to the threads on the spindle.

3.2 Shrink Fit the Spindle Bearing Cone

1

Lower the spindle bearing cone over the spindle.

2

Apply a layer of grease to the bearing cone.

3

Correctly position the oil seals into the lower spindle retainer.

4

Apply a layer of grease to the seal lips and in between the oil seals.

3.3 Expansion Fit the Lower Housing Bearing Cup

1

Install the lower housing bearing cup into the housing and seat it fully.

2

Apply a thin layer of grease to the bearing cup surface.

3-4

Install the spindle into the housing.

5

Heat the oil seal wear sleeve.

6

Put the wear sleeve over the spindle and seat it fully.

7

Heat the output gear.

8

Heat the both intermediate gears.

9

Lubricate the O-ring and position on the lower spindle retainer.

10

Put the lower spindle retainer around the spindle.

11

Install the plug into dedicated place in the side of the lower spindle retainer.

12

install the bottom and side housing plugs, sight glass, and strainer.

13

Reposition the housing.

14

Use a jack to support the spindle from the bottom so that both the lower spindle bearing cup and cone are pressed tightly together.

15

Insert the key into the keyway of the spindle.

16

Make sure that the bearing cups are seated tightly against the mounting surfaces in the housing.

17

Apply a thin layer of grease to both bearing cup running surfaces.

3.4 Shrink the Fit Output Gear

1-2

Install the output gear over the spindle.

3

Put the retaining collar around the spindle to keep the output gear in place.

4

Secure the retainer collar with bolts and elastic stop nuts.

3.5 Shrink Fit the Intermediate Upper Bearing Cone and the Gear Assembly

1

Heat the two lower intermediate bearings cones.

2

Slide the lower intermediate bearing cones over the intermediate shafts.

3-4

Put the keys in keyways of the intermediate shafts. Slide the each hot output gear over the intermediate shaft and seat it fully.

3.6 Shrink Fit the Spacers and the Lower Intermediate Bearing Cones

1

Heat the spacers.

2-3

Put the spacers onto the intermediate shafts.

4

Heat the lower intermediate shaft bearing cones. Slide each intermediate shaft bearing cone over the end of its respective intermediate shaft.

5

Insert the oil seal into the spacer.

6

Lower the intermediate shaft subassembly carefully into the intermediate bearing cup.

7

Install the upper and the lower ball bearings onto the input pinions.

8

Install a drive key and a snap ring onto the one input pinion shaft subassembly.

9

Make sure that the lubrication pump drive adapter fits correctly into the input pinion subassembly.

10

Apply a thin layer of grease to the housing bores and the outer races on the lower input pinion bearings.

11

Make sure that the intermediate shafts are seated fully.

12

Apply a layer grease to the intermediate shaft seal lips, the rollers on the upper intermediate bearings, and the outer races of the input pinion.

13

Apply a bead of silicone to the mounting surface of the housing.

14-15

Install the cover on the housing and secure it with bolts.

16

Insert the snap-rings inside the housing cover.

17

Fill a small amount of silicone in the threaded bolt holes in the upper spindle bearing cavity area.

18

Apply oil seal lip with a layer of grease and install the oil seal over the spindle and into the housing cover.

19

Lubricate the O-ring with a thin layer of grease and put it over the bearing holder into the O-ring groove.

20

Apply a thin layer of grease to the upper intermediate bearing rollers and to the inside surfaces of the intermediate bearing cavities.

21

Slide the bearing holders into position in the housing cover and then fully seat them.

22-23

Apply a thin layer of grease to the roller mounting surface and the outside diameter of the upper intermediate bearing cup. Install the bearing cups into the bearing holders.

24

Apply a thin layer of grease to the outside diameter of intermediate bearing adjusters and insert them into the bearing holders.

25

Install adapters, grease fittings, and relief fittings.

26-27

Install bolts and washers on the bearing holders and the bearing adjusters. Tighten the bolts.

3.7 Set the Intermediate Bearing Pre-load

1

Make sure that the intermediate bearings rollers are seated fully.

2-5

Measure the shim thickness required on the bearing adjuster.

6

Install the correct shim sets over the bearing adjuster and install the O-rings.

7

Apply the outside diameters of both bearing adjusters with a thin layer of grease and install into the bearing holders.

8

Install an elbow with a relief fitting into the housing cover.

3.8 Expansion Fit the Upper Spindle Bearing Cup

1-2

Press the upper spindle bearing cup into the housing cover and seat it fully.

3.9 Shrink Fit the Upper Spindle Bearing Cone

1

Heat the upper spindle bearing cone.

2

Apply a thin layer of grease to the bearing cup running surface.

3

Put the upper spindle bearing cone onto the spindle.

3.10 Setting the Spindle Bearing Preload Rolling Torque

1

Install the adjusting nut on the spindle and seat it fully.

2-9

Adjust the preload torque.

10

Put tongued washer over the spindle and secure it with bolts.

3.11 Shrink the Fit Wear Sleeve

1

Heat the wear sleeve.

2

Insert both grease fitting and relief fitting into the swivel housing.

3

Apply grease to swivel housing, O-ring, upper spindle bearing cavity, and bearing rollers.

4

Correctly orient the swivel housing with the lubrication fitting.

5

Insert and torque the bolts on the swivel housing.

6-7

Apply a layer of grease to the oil seals and install them into the swivel housing

8

Put a drip shield and a plastic locking ring around the spindle.

9

Apply a thin layer of grease to the spindle threads. Put the O-ring into groove at the top of the spindle. Apply grease to the O-ring.

10-12

Put the spindle cap over the spindle and tighten it.

13-15

Insert swivel packing into the spindle cap and swivel cover. Apply Loctite to the swivel packing.

16

Insert the wear bushing inside of the spindle cap.

17

Install the shims.

18

Secure the swivel cover in place with bolts.

19

Insert the adapters into the housing cover for both motors.

20

Apply grease to the motor adapter. Put the O-ring. Align the motor adapters to the lubrication pump hosing.

21

Apply grease to the motor covers and install the O-rings. Install the covers and secure them with bolts.

22-23

Install lubrication pump below the housing.

24

Insert the bolts. Connect the suction hose. Attach the fittings.

25

Secure the hoses to the housing with a clamp.

26

Insert the rotation tachometer sensor.

27

Fill the gear oil until the sight glass is at least half full.

Spur Gear Rotary Head Specifications and Lubricants

Specifications

Design

Two stages, spur gear

Speed range

Variable, 0 to 160 rpm

Maximum torque

25,760 Nm (19,000 ft/lb) @ 95 rpm - 100% efficiency

14,236 Nm (10,500 ft/lb) @ 170 rpm - 100% efficiency

Rotary head motor

Quantity-two, 229 cm3/ rev (14 in3/ rev)

Reduction

14.8:1

Main gear face width

152 mm (6 in)

Head guides

Replaceable, Nylatron (moly - disulfide) @ 1,626 mm (64 in) contact length each side.

Rotary head weight (bare)

1,179 kg (3,376 lb)

Function

Rotate the drill bit

Lubricants

Item

Type

Capacity

Rotary head grease

Ronex Extra HD Moly 2

Add grease until the relief valve pops out

Rotary head oil

SAE 80W90 gear oil

SHC 634 is optional

208 L (55 gal)

Fill to mark on the sight level gauge

The SSU viscosity at 37 °C (100 °F) must be at a minimum of 2,060, and at 99 °C (210 °F), 189. Maximum pour point is -40 °C (-40 °F).

Torque Values

CAUTION

Incorrect Tool Usage

Incorrect tools used with incorrect fittings can slip and cause injury.

  1. Use the correct tools (standard or metric) based on the type of operation.

  • Do not use these values if a different torque value or tightening procedure is listed for a specific application. Torque values listed are for general use only. All values are suggested maximum with dry-plated fasteners.

  • Make sure that fastener threads are clean. Start the thread engagement correctly to prevent the fastener from failing when tightening.

  • The following pages list the recommended tightening torques for various size cap screws. Correct torque specifications should be used at all times.

  • The head of a Grade 5 fastener is marked with three short lines. The head of a Grade 8 is marked with six short lines.

  • In the following tables, Dry means clean dry threads and lubricated means a light film of oil. Excess oil in a threaded dead end hole can create a hydraulic lock, giving a false torque reading.

NOTE

Torque values outside of the general information contained here will be contained in the specific procedures for which they apply.

Standard Bolt Torque Values

NOTE

Use only the proper tools (inch or metric) on hardware. Other tools cannot fit properly and can slip and cause injury.

Fasteners must be replaced with the same grade or a higher grade. If higher grade fasteners are used, then tighten them only to the strength of the original grade fastener.

  • Do not use the values from recommended torque tables if a different torque value or tightening procedure is listed for a specific application. Torque values listed are for general use only. All values are suggested maximum with dry plated hardware.

  • Make sure that fastener threads are clean. Properly start thread engagement to prevent the fastener from failing when tightening.

  • Always use proper torque specifications.

  • The head of a Grade 5 fastener is marked with three short lines. The head of a Grade 8 is marked with six short lines.

  • In the following tables, Dry means clean dry threads and Lube means a light film of oil. Excess oil in a threaded dead end hole can create a hydraulic lock, giving a false torque reading.

Standard Head Markings

A

Grade 5 capscrew head marking

B

Grade 8 capscrew head marking

Recommended Torques of Standard Bolts in Foot-Pounds

This table lists the recommended tightening torques in foot/pounds (ft·lb) for the various size bolts and nuts that are used. The suggested assembly torque values are per engineering specifications.

Recommended Torques of Standard Bolts in Foot-Pounds

Size

SAE Grade 5

SAE Grade 8

Dry

Lube

Dry

Lube

5/16 - 18 NC

5/16 - 24 NF

16 - 17

18 - 19

12 - 13

13 - 14

23 - 25

-

17 - 18

19 - 20

3/8 - 16 NC

3/8 - 24 NF

28 - 30

33 - 35

21 - 23

23 - 25

42 - 45

47 - 50

33 - 35

-

7/16 - 14 NC

7/16 - 20 NF

47 - 50

51 - 55

33 - 35

37 - 40

65 - 70

74 - 80

51 - 55

56 - 60

1/2 - 13 NC

1/2 - 20 NF

70 - 75

84 - 90

51 - 55

61 - 65

102 - 110

112 - 120

74 - 80

84 - 90

9/16 - 11 NC

9/16 - 18 NF

102 - 110

112 - 120

74 - 80

84 - 90

140 - 150

158 - 170

102 - 110

121 - 130

5/8 - 11 NC

5/8 - 19 NF

140 - 150

158 - 170

102 - 110

121 - 130

205 - 220

223 - 240

158 - 170

167 - 180

3/4 - 10 NC

3/4 - 16 NF

242 - 260

279 - 300

186 - 200

205 - 220

353 - 380

391 - 420

260 - 280

298 - 320

7/8 - 9 NC

7/8 - 14 NF

400 - 430

437 - 470

298 - 320

326 - 350

558 - 600

614 - 660

428 - 460

465 - 500

1 - 8 NC

1 - 12 NF

595 - 640

651 - 700

446 - 480

493 - 530

837 - 900

930 - 1000

632 - 680

688 - 740

1-1/8 - 7 NC

1-1/8 -12 NF

744 - 800

818 - 880

558 - 600

614 - 660

1190 - 1280

1339 - 1440

893 - 960

1004 - 1080

1-1/4 - 7 NC

1-1/4 - 12 NF

1042 - 1120

1153 - 1240

781 - 840

856 - 920

1693 - 1820

1860 - 2000

1255 - 1360

1395 - 1500

1-3/8 - 6 NC

1-3/8 - 12 NF

1358 - 1460

1562 - 1680

1023 - 1100

1172 - 1260

2213 - 2380

2530 - 2720

1655 - 1780

1897 - 2040

1-1/2 - 6 NC

1804 - 1940

1358 - 1460

2939 - 3160

2195 - 2360

Recommended Torques of Standard Bolts in Newton-Meters

This table lists the recommended tightening torques in Newton-meters (N·m) for the various size bolts and nuts that are used. The suggested assembly torque values are per engineering specifications.

Recommended Torques of Standard Bolts in Newton-Meters

Size

SAE Grade 5

SAE Grade 8

Dry

Lube

Dry

Lube

5/16 - 18 NC

5/16 - 24 NF

22 - 27

24 - 26

16 - 17

17 - 19

31 - 33

-

23 - 24

26 - 27

3/8 - 16 NC

3/8 - 24 NF

37 - 40

44 - 47

28 - 31

31 - 33

56 - 60

63 - 67

44 - 47

-

7/16 - 14 NC

7/16 - 20 NF

63 - 67

68 - 73

44 - 47

49 - 53

87 - 93

97 - 107

68 - 73

75 - 80

1/2 - 13 NC

1/2 - 20 NF

93 - 100

112 - 120

68 - 73

81 - 87

136 - 147

149 - 160

99 - 107

112 - 120

9/16 - 12 NC

9/16 - 18 NF

136 - 147

149 - 160

99 - 107

112 - 120

187 - 200

211 - 227

136 - 147

161 - 173

5/8 - 11 NC

5/8 - 18 NF

187 - 200

211 - 277

136 - 147

161 - 173

273 - 293

297 - 320

281 - 227

223 - 240

3/4 - 10 NC

3/4 - 16 NF

323 - 347

372 - 400

248 - 267

273 - 293

471 - 507

521 - 560

347 - 373

397 - 427

7/8 - 9 NC

7/8 - 14 NF

533 - 573

583 - 627

397 - 427

435 - 467

744 - 800

819 - 880

571 - 613

620 - 667

1 - 8 NC

1 - 12 NF

793 - 853

868 - 933

595 - 640

657 - 707

1116 - 1200

1240 - 1333

843 - 907

917 - 987

1-1/8 - 7 NC

1-1/8 -12 NF

992 - 1067

1090 - 1173

774 - 800

819 - 880

1587 - 1707

1785 - 1920

1191 - 1280

1339 - 1440

1-1/4 - 7 NC

1-1/4 - 12 NF

1389 - 1493

1537 - 1653

1041 - 1120

1141 - 1227

2257 - 2427

2480 - 2667

1687 - 1813

1860 - 2000

1-3/8 - 6 NC

1-3/8 - 12 NF

1811 - 1947

2083 - 2240

1364 - 1467

1563 - 1680

2951 - 3173

3373 - 3627

2207 - 2373

2529 - 2720

1-1/2 - 6 NC

2405 - 2587

1811 - 1947

3917 - 4213

2927 - 3147

Servicing Time Tables

NOTE

Duty Guidelines / Definitions:

  • Light - Sand and gravel, rotary drilling

  • Normal - Soft rock, rotary drilling

  • Heavy - Hard rock, hammer drilling

NOTE

Life cycle calculation is based on the average expected life of the part. It does not imply that the part is covered under any warranty for that period.

Mean Time Between Service (MTBS)

Rotary Head Oil Level Check and Upper Bearing Greasing

Light duty

Normal duty

Heavy duty

8–10 hours or daily

8–10 hours or daily

8–10 hours or daily

Mean Time Between Maintenance (MTBM)

Change Rotary Head Oil

Light duty

Normal duty

Heavy duty

1,200 hours

1,000 hours

800 hours

Mean Time Between Failure (MTBF)

Average Time Between Recommended Rotary Head Rebuilds

Light duty

Normal duty

Heavy duty

12,000 hours

10,000 hours

8,000 hours

Mean Time To Repair (MTTR)

Average To Remove From Machine

Average To Rebuild Rotary Head

8–10 hours

16–20 hours

Required Tools and Special Equipment

Before starting the rotary head rebuild, certain special tools are necessary and available from Epiroc. Many of these tools are in a Rotary Head Rebuild Tools Kit. See table Rotary Head Rebuild Tools Kit.

NOTE

Refer to Rotary Head Rebuild Tools Kit drawing.

Rotary Head Rebuild Tools Kit

Spindle seal tool

Spindle nut tool

Lock nut adjustment tool

Spindle rotation tool

Rotary head rebuild stand

Input pinion tool

Puller rod tool

Puller plate tool

Spindle nut stop tool, assembly

Puller cap plate tool

Stop angle tool

Bolt, jacking

Bolt, jacking

Hex-heavy nut, 1-8

Some additional tools are necessary for this rotary head model that are not included with the Rotary Head Rebuild Tools Kit, but are necessary for a successful rebuild. These tools include:

  • Round plate with holes

  • Tee rod hook

  • Lock-ring tool

  • Various size threaded eye bolts

  • Torque wrenches

  • Shackle

  • Insulated gloves

  • Claw type bearing puller

  • Lifting straps

  • 25-ton long stroke bottle jack

  • Induction heater or oil bath heater capable to 232 °C (450 °F)

  • Hoist with a minimum of 9,072 kg (20,000 lb) capacity

  • Hydraulic press

  • Large and small snap ring pliers

Rotary Head Rebuild Reference Numbers

Rotary Head Rebuild Kit Number / Bare Part Number

Rebuild Parts Kit

Rebuild Tool Kit

Rotary Head Part

2657817488

2657618142

2657653693 bare housing

Correct Bearing Oil Seal Orientation

The lip of the seal points to the highest pressure side (see arrow). Seals can be doubled.

For oil retention, the seal lip must be mounted with the lip pointing inwards toward the bearing and oil cavity to seal in the oil. The bearing seal has a spring retention design system. The spring must be towards the inside of the cavity.

A

Seal lip

B

Spring

Safety Messages in Publications

Safety messages in publications declare hazards and the related measures to avoid the hazards in that particular situation. Safety messages contain signal words (Danger, Warning, Caution, and Notice) that relate to the consequences of those specific hazards. The information in safety messages must be obeyed.

Safety messages consist of:

  • A signal word to determine the degree of the hazard.

  • A type of hazard states the potential source of a hazard. For example: Moving parts, Hot surface, and so on.

  • The consequence of the hazard, if not avoided.

  • A method to avoid the hazard.

The following are examples of safety message structures.

DANGER

Hazard

The signal word "DANGER" indicates a hazardous situation which will result in death or serious injury if not avoided.

  1. The method to avoid the hazard is written here.

WARNING

Hazard

The signal word "WARNING" indicates a hazardous situation which could result in death or serious injury if not avoided.

  1. The method to avoid the hazard is written here.

CAUTION

Hazard

The signal word "CAUTION" indicates a hazardous situation which could result in minor or moderate injury if not avoided.

  1. The method to avoid the hazard is written here.

NOTICE

Hazard

The signal word "NOTICE" contains information that is not related to bodily injury yet considered important. In a "NOTICE" the damage is related to machines, components, or systems.

  1. The method to avoid the hazard is written here.

Preventive Maintenance Inspections

NOTICE

Rotary Head Damage

Incorrect preload on the Main Bearing Assembly reduces the service life of the rotary head.

Repeated problems with the Swivel Head Packing Assembly, such as water leaks and missing packing rings, could be an indication of loss of preload on the Main Bearing Assembly.

Insufficient preload lets the upper spindle bearing inner-race spin below the lock nut during drilling and breakout operations. The spinning of the race quickly wears away the bottom of the lock nut and any existing preload is lost, resulting in endplay. The endplay in the Spindle Assembly is harmful to bearings and other components.

Excessive preload overloads the bottom spindle bearing, which leads to loss of preload and early failure.

Reapplying preload to spindle bearing causes early bearing failure.

  1. Apply correct preload on the Main Bearing Assembly.

In addition to the rotary head service recommendations in the Maintenance manual, the following is suggested:

  1. 1.
    Test oil samples every 500 hours.
    1. Create a chart to track any changes in the content of dissolved metals or contaminants.
    2. Changes must be fairly linear. Any sudden or dramatic changes in oil samples could be an indication that there has been a loss of preload on the main bearing, or problems elsewhere.
    3. Any major changes are noted in the metal content of the oil. If a dramatic loss of preload or other serious problem is discovered or observed, consult Epiroc Technical Services.
  2. 2.
    Change the rotary head oil every 1,000 hours. For more information, see table Mean Time Between Service.
    • Examine the magnetic drain plug, strainer, and oil for evidence of ground-up metal shavings.

    NOTE

    Excessive amounts of metal shavings could be an indication of a problem.

  3. 3.
    Examine the preload every 2,000 hours.
    1. Use a machinist's magnetic base with an adjustable arm and a dial-gauge attached to the end.
    2. Put the dial-gauge on top of the spindle.
    3. Examine vertical movement of the spindle and track the reading.
    4. Measure horizontal runout by placing the dial-gauge on the side of the spindle and using the motor to rotate the spindle.

Safety Precaution

The following safety, cleanliness and maintenance guidelines are to be used throughout the assembly and disassembly process for the rotary head:

  • Clean the exterior of the rotary head before disassembling it.

  • Use applicable personal protective equipment.

  • Disassemble the rotary head in a clean area.

  • Pay close attention to the identities of the parts during disassembly; this makes reassembly much easier.

  • Use a soft-faced hammer and soft drifts to remove heavier parts.

  • Handle parts carefully. Hardened parts can chip or break if they are dropped on a hard surface.

  • Clean all parts thoroughly in an approved cleaning solvent and blow dry with compressed air. Do this in a well-ventilated area.

  • Inspect all bearings, gears, and shafts for wear, cracks, discoloration, and/or looseness. Examine all new parts for damage that can have occurred in shipment and replace all unserviceable parts.

  • Remove all nicks, burrs, or any foreign matter from the rotary head housing, inside, and out.

  • Do not let dirt, cuttings, or brass shavings enter the rotary head during assembly.

  • Keep hands and tools clean.

  • Wipe a film of oil over all working parts such as bearings, shafts, seals, and O-rings as they are assembled, except where specified otherwise.

  • Except for press-fit bearings and bushings, parts must fit together easily. If force is necessary, a part is either out of tolerance or alignment, and must be corrected to prevent binding and possible damage.