ST Spindle Actuator and Adapter Replacement Guide

Rebuilding the Hydraulic Union

The following service video shows how to rebuild a hydraulic union.

Note : This service video is for reference only and does not replace the written procedure

Introduction

This document covers the replacement procedure for hydraulic actuators and adapters for ST-10/15/20/25/30/35/40/45 machines.

You do not need to replace an adapter when replacing a hydraulic actuator. Only replace if damaged.

Important : If you are working on a ST-20/25/30 that has a slip fit adapter, you will also need to replace the drive sprocket. Machines built after 11/20/2018 will have sweat fit adapters and you will not need to replace the drive sprocket.

Use the Drawtube Removal Tools to remove the Hydraulic Union from the drawtube.

Caution: If the Drawtube Removal Tools are not used to remove the drawtube, the anti-rotation pins can shear in the hydraulic union.

Drawtube Removal Tools

Hydraulic Actuator and/or Adapter Replacement

1

Remove the Hydraulic Actuator

Remove the coolant collector cover, surrounding sheet metal, and anti-rotation bracket that seats around hydraulic actuator drain hose
Lock the spindle to prevent it from rotating
Break the screws [1] loose that connect the adapter to the actuator
Power off the machine
Disconnect the hydraulic lines [5] from the hydraulic actuator [2]. Note the clamp/unclamp hose and port orientation. Mark the hose and port if necessary
- Note: Have plugs or baggies and rubber bands to cover the hoses to prevent hydraulic fluid from coming out and debris from getting in. Keep the hoses pointed up and tucked away on the side of the spindle to prevent fluid from coming out
Fully remove the rest of the screws and slowly remove the union and drawtube assembly
- Caution: The actuator is heavy and if dropped or banged it could receive permanent damage
- Have a box or table nearby with padding to lay the actuator in and support the drawtube
Note: You only need to remove the adapter if it's damaged and you are replacing it, otherwise leave the current adapter installed and only replace the actuator
- Remove the adapter screws [3] that secure the adapter [4] to the spindle shaft.
- If necessary, heat the adapter with a heat gun to release it from the spindle shaft [4]

2

Optional: Install new spindle actuator adapter plate

If you need to replace the adapter, follow this step, otherwise skip to Step 3
If you have a ST-20/25/30 - Please read the last section before continuing:

The new adapters are a sweat fit to the spindle shaft.
A hot plate will work best to uniformly heat the adapter
- Caution: Do not exceed 230 °F (110 °C) when heating the adapter
Place the adapter smaller diameter face down on the hot plate
- Caution: Be sure to use high temperature heat resistant gloves when sweat fitting the adapter
When you install the adapter you must move quickly as the aluminum will cool fast
With the adapter at about 230 °F (110 °C) on the hot plate - take one screw [1] and put it into the adapter washer [2] to have it ready
With gloves on, using both hands, take the adapter and quickly slip it onto the shaft
Press evenly on both sides, until you feel it seat
Rotate it until the hole patterns line up
Take the screw and adapter washer and quickly run down the one screw into a hole
Quickly run the rest of the screws down in a star pattern
Torque the screws in a star pattern to ensure the adapter seats
- Haas Torque Chart
Then break the screws loose but leave them snug while the adapter cools
Torque screws again once the adapter has cooled
Once cooled measure the inner radial runout [3], not to exceed 0.001"
Measure the axial runout [4], not to exceed 0.0005"
- Production Tip: If you find that you're having a hard time getting the adapter to seat and have accepatable runout, then try the following. After you slip the hot adapter on the shaft, snug all the screws down, and then lightly indicate the adapter on the inner radius [3] while using a plastic mallet on the outer diameter. When the runout is within spec, slowly torque all of the screws down in a star pattern being careful not to induce runout.

3

Install New Actuator

Install the union and snug the screws
Place an indicator on the steel strip [1], runout not to exceed 0.0005"
Indicate in if necessary
Place an indicator on the coolant collector [2]. Rotate the union and measure how much the indicator deflects, not to exceed 0.001"
- If the runout exceeds 0.001" please see the alignment section of the Lathe Vibration Troubleshooting Guide
Torque the screws in a star pattern
- Haas Torque Chart
Re-install the hydraulic hoses
- Caution: Do NOT over tighten the hose fittings. This could cause the aluminum housing to crack.
Re-install anti-rotation bracket around drain hose
Power on machine and test clamp/unclamp
Run the spindle take a vibration test to ensure all components are aligned.
Check results against Lathe Spindle Vibration Tolerances
Re-install surrounding sheet metal and coolant collector box

Note: Add dielectric grease to all surfaces of the coolant collector seal ring.

Adapter and Sprocket Part Number Identification

Login to the HBC PORTAL.

Click on service tab then select utilities.

Select Bill of materials and input machine serial number then select your machine.

Type "Adapter" / "Closer" / "Union" / "ADPTR" in the material search bar and determine which one is needed for your application. If none of the above terms find the union adapter then a different approach would be to search "SPNDL OPT" and search the listed components.

Type "SPKT" in the material search bar to determine which sprocket is needed for your application.

Exceptions for ST-20/25/30 Actuator and/or Adapter Replacement

1

Optional: Replace drive sprocket if required when replacing the adapter plate
Determine sprocket part number through HBC
If you need to replace the adapter for the hydraulic union on a ST-20,25,30 - then see the following:
Note: You do not need to replace the adapter when you are replacing the hydraulic actuator unless it has damage.
For ST-20's, 25's and 30's the steps are the same as above, except if the adapter is a slip fit (has clearance), then the drive sprocket will also need to be replaced to allow for dimensional changes in the new hydraulic actuator adapter plate.
- Machines built after 11/20/2018 will have sweat fit adapters and will not need the drive sprocket replaced.
This section will only cover the drive sprocket replacement- See the previous section for section regarding the adapter plate and actuator.
Break loose the motor mount plate screws [4]
Loosen the nut on the tensioner block [3] and loosen the belt tension on the belt by turning the socket head cap screw (SHCS) counter-clockwise
Remove the belt from the pulley
Break loose the drive sprocket [1] screws
Remove the drive sprocket
Align the new drive sprocket hole pattern with the holes on the spindle lock [2]
Install the screws and torque per the Haas Torque Chart
Re-install the belt
Re-tension the belt by turning the SHCS clockwise
- Check belt tension with a Gates Sonic Meter per Haas Belt Tension specs
Tighten the nut on the SHCS once tension is achieved
Torque the motor mount plate screws per the Haas Torque Chart
Always check the gap between the non-contact encoder read head and the encoder ring after re-setting belt tension
Adjust the encoder gap at the high spot on the encoder ring if necessary

Coolant Collector Installation

Refer to Coolant Collector Replacement - ST-20 - AD0432 for instructions regarding installing the coolant collector.