Walschaert valve gear - Revision history

Dnevil: /* Video */

2024-04-05T19:29:39Z

Video

← Older revision		Revision as of 14:29, 5 April 2024
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	<youtube>LU-KgJVlZ0M</youtube>		<youtube>LU-KgJVlZ0M</youtube>
			<br><br>

			<youtube>O6rlfXCsoPk</youtube>
	<br><br>		<br><br>

Dnevil: /* Video */

2022-03-02T04:08:26Z

Video

← Older revision		Revision as of 23:08, 1 March 2022
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	<youtube>rRGGSr68miQ</youtube>		<youtube>rRGGSr68miQ</youtube>
			<br><br>

			<youtube>LU-KgJVlZ0M</youtube>
	<br><br>		<br><br>

Dnevil: /* External Links */

2022-03-02T04:07:37Z

External Links

← Older revision		Revision as of 23:07, 1 March 2022
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	* [http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=101842 "Help with Charlie Dockstader Program", <i>Chaski.org</i>]		* [http://www.chaski.org/homemachinist/viewtopic.php?f=8&t=101842 "Help with Charlie Dockstader Program", <i>Chaski.org</i>]
	* [https://www.jghtech.com/assets/applets/LFLSRM-Setting-Eccentric-Crank-current.pdf "Setting the Eccentric Crank", Jeffrey G. Hook, <i>Deerfield & Roundabout RR</i>]		* [https://www.jghtech.com/assets/applets/LFLSRM-Setting-Eccentric-Crank-current.pdf "Setting the Eccentric Crank", Jeffrey G. Hook, <i>Deerfield & Roundabout RR</i>]
			* [https://www.chaski.org/homemachinist/viewtopic.php?t=111427 "How to Design Walschaerts Valve Gear", <i>Chaski.org</i>]

Dnevil: /* Unequal travel */

2021-12-10T04:45:02Z

Unequal travel

← Older revision		Revision as of 23:45, 9 December 2021
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	# Then to check length of eccentric rod, again set piston on front [[Dead center\|dead-center]] and move gear up and down. Valve should not move. The same for back dead-center.		# Then to check length of eccentric rod, again set piston on front [[Dead center\|dead-center]] and move gear up and down. Valve should not move. The same for back dead-center.
	# Then set valve to get equal leads, front and back, when radius rod is in mid gear (or in the center of the link).		# Then set valve to get equal leads, front and back, when radius rod is in mid gear (or in the center of the link).

	~~== Unequal travel ==~~

	~~[https://www.chaski.org/homemachinist/viewtopic.php?t=98490&start=48 Marty Knox wrote on <i>Chaski.org</i>]:~~

	: Baker Valve Gear does not travel the same distance either side of center between ports. Baldwin made the front and back bushings different lengths to compensate. They gave you a dimension to add to one end and subtract from the other end. Here is the diagram from Baldwin Standard Practices.

	~~[[File:Baker VG bushings.jpg\|thumb\|center\|500px]]~~

	== Video ==		== Video ==

Dnevil: /* Unequal travel */

2021-12-10T04:44:36Z

Unequal travel

← Older revision		Revision as of 23:44, 9 December 2021
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	: Baker Valve Gear does not travel the same distance either side of center between ports. Baldwin made the front and back bushings different lengths to compensate. They gave you a dimension to add to one end and subtract from the other end. Here is the diagram from Baldwin Standard Practices.		: Baker Valve Gear does not travel the same distance either side of center between ports. Baldwin made the front and back bushings different lengths to compensate. They gave you a dimension to add to one end and subtract from the other end. Here is the diagram from Baldwin Standard Practices.

	[File:Baker VG bushings.jpg\|thumb\|center\|500px]]		[[File:Baker VG bushings.jpg\|thumb\|center\|500px]]

	== Video ==		== Video ==

Dnevil: /* Setting */

2021-12-10T04:44:17Z

Setting

← Older revision		Revision as of 23:44, 9 December 2021
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	# Then to check length of eccentric rod, again set piston on front [[Dead center\|dead-center]] and move gear up and down. Valve should not move. The same for back dead-center.		# Then to check length of eccentric rod, again set piston on front [[Dead center\|dead-center]] and move gear up and down. Valve should not move. The same for back dead-center.
	# Then set valve to get equal leads, front and back, when radius rod is in mid gear (or in the center of the link).		# Then set valve to get equal leads, front and back, when radius rod is in mid gear (or in the center of the link).

			== Unequal travel ==

			[https://www.chaski.org/homemachinist/viewtopic.php?t=98490&start=48 Marty Knox wrote on <i>Chaski.org</i>]:

			: Baker Valve Gear does not travel the same distance either side of center between ports. Baldwin made the front and back bushings different lengths to compensate. They gave you a dimension to add to one end and subtract from the other end. Here is the diagram from Baldwin Standard Practices.

			[File:Baker VG bushings.jpg\|thumb\|center\|500px]]

	== Video ==		== Video ==

Dnevil: /* Video */

2021-01-06T04:41:03Z

Video

← Older revision		Revision as of 23:41, 5 January 2021
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	== Video ==		== Video ==

	<br><~~videoflash~~>b7NABUkyGok</~~videoflash~~>		<br><youtube>b7NABUkyGok</youtube>
	<br><br>		<br><br>

	<~~videoflash~~>rRGGSr68miQ</~~videoflash~~>		<youtube>rRGGSr68miQ</youtube>
	<br><br>		<br><br>

Dnevil at 02:47, 20 August 2019

2019-08-20T02:47:39Z

Dnevil at 02:42, 20 August 2019

2019-08-20T02:42:30Z

← Older revision		Revision as of 21:42, 19 August 2019
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	<i>[[The Live Steamer]]</i>, January-February 1951		<i>[[The Live Steamer]]</i>, January-February 1951

	With [[Walschaert valve gear]] the length of the radius rod and the eccentric rod is dependent on the fore and aft location of the swinging link. In most layous of Walschaert gear, the link is located approximately halfway between the centers of the main driving axle and the valve stem crosshead, to which the combination lever is attached. The radius of the link is the length of the radius rod measured from the center of its connection at the combination lever, to the center of the bearing on which the link swings.		With [[Walschaert valve gear]] the length of the radius rod (8) and the eccentric rod (2) is dependent on the fore and aft location of the swinging link. In most layous of Walschaert gear, the link is located approximately halfway between the centers of the main driving axle and the valve stem crosshead, to which the combination lever is attached. The radius of the link is the length of the radius rod measured from the center of its connection at the combination lever, to the center of the bearing on which the link swings.

	If the radius of the link was not equal to this distance, it would be impossible to move the radius rod from top to bottom of the link without moving the valve and it must be possible to do this without moving the valve for accurate valve setting.		If the radius of the link was not equal to this distance, it would be impossible to move the radius rod from top to bottom of the link without moving the valve and it must be possible to do this without moving the valve for accurate valve setting.

Dnevil at 02:41, 20 August 2019

2019-08-20T02:41:34Z

← Older revision		Revision as of 21:41, 19 August 2019
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	[[Category:Steam Locomotive Parts]]		[[Category:Steam Locomotive Parts]]

	[[File:Walschaert static.png\|thumb\|right\|500px\|Walschaert valve gear for inside admission piston valves <br>1. Eccentric Crank (Return Crank) <br>2. Eccentric Rod <br>3. Reach Rod <br>4. Lifting Link <br>5. Lifting Arm <br>6. Reverse Arm & Shaft <br>7. Link (Expansion Link) <br>8. Radius ~~Bar~~ <br>9. Crosshead Arm (Drop Link) <br>10. Valve Stem Guide <br>11. Union Link (Anchor Link) <br>12. Combination Lever <br>13. Valve Stem 14. Valve Spindle]]		[[File:Walschaert static.png\|thumb\|right\|500px\|Walschaert valve gear for inside admission piston valves <br>1. Eccentric Crank (Return Crank) <br>2. Eccentric Rod <br>3. Reach Rod <br>4. Lifting Link <br>5. Lifting Arm <br>6. Reverse Arm & Shaft <br>7. Link (Expansion Link) <br>8. Radius Rod <br>9. Crosshead Arm (Drop Link) <br>10. Valve Stem Guide <br>11. Union Link (Anchor Link) <br>12. Combination Lever <br>13. Valve Stem 14. Valve Spindle]]

	== Radius Rod ==		== Radius Rod ==

← Older revision		Revision as of 21:47, 19 August 2019
Line 1:		Line 1:
	[[Category:Steam Locomotive Parts]]		[[Category:Steam Locomotive Parts]]

	[[File:Walschaert static.png\|thumb\|right\|500px\|Walschaert valve gear for inside admission piston valves <br>1. Eccentric Crank (Return Crank) <br>2. Eccentric Rod <br>3. Reach Rod <br>4. Lifting Link <br>5. Lifting Arm <br>6. Reverse Arm & Shaft <br>7. Link (Expansion Link) <br>8. Radius Rod <br>9. Crosshead Arm (Drop Link) <br>10. Valve Stem Guide <br>11. Union Link (Anchor Link) <br>12. Combination Lever <br>13. Valve Stem 14. Valve Spindle]]		[[File:Walschaert static.png\|thumb\|right\|500px\|Walschaert valve gear for inside admission piston valves <br>1. Eccentric Crank (Return Crank) <br>2. Eccentric Rod <br>3. Reach Rod <br>4. Lifting Link <br>5. Lifting Arm <br>6. Reverse Arm & Shaft <br>7. Link (Expansion Link) <br>8. Radius Rod <br>9. Crosshead Arm (Drop Link) <br>10. Valve Stem Guide <br>11. Union Link (Anchor Link) <br>12. Combination Lever <br>13. Valve Stem <br>14. Valve Spindle]]

	== Radius Rod ==		== Radius Rod ==
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	<i>[[The Live Steamer]]</i>, January-February 1951		<i>[[The Live Steamer]]</i>, January-February 1951

	With [[Walschaert valve gear]] the length of the radius rod (8) and the eccentric rod (2) is dependent on the fore and aft location of the ~~swinging~~ link. In most layous of Walschaert gear, the link is located approximately halfway between the centers of the main driving axle and the valve stem ~~crosshead~~, to which the combination lever is attached. The radius of the link is the length of the radius rod measured from the center of its connection at the combination lever, to the center of the bearing on which the link swings.		With [[Walschaert valve gear]] the length of the radius rod (8) and the eccentric rod (2) is dependent on the fore and aft location of the expansion link (7). In most layous of Walschaert gear, the expansion link is located approximately halfway between the centers of the main driving axle and the valve stem guide (10), to which the combination lever (12) is attached. The radius of the expansion link is the length of the radius rod measured from the center of its connection at the combination lever, to the center of the bearing on which the link swings.

	If the radius of the link was not equal to this distance, it would be impossible to move the radius rod from top to bottom of the link without moving the valve and it must be possible to do this without moving the valve for accurate valve setting.		If the radius of the link was not equal to this distance, it would be impossible to move the radius rod from top to bottom of the link without moving the valve and it must be possible to do this without moving the valve for accurate valve setting.

	This condition is also a must for checking the length of eccentric rod and position of the eccentric crank.		This condition is also a must for checking the length of eccentric rod (2) and position of the eccentric crank (1).

	== Setting ==		== Setting ==
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	# Get front and back dead-center.		# Get front and back dead-center.
	# Make dummy pin for link tail with shoulder sticking out.		# Make dummy pin for link tail with shoulder sticking out.
	# Then set the link in mid position so that the radius rod passes up and down without moving the link. Have valve on center of seat.		# Then set the expansion link in mid position so that the radius rod (8) passes up and down without moving the link. Have valve on center of seat.
	# Use inside calipers. Set piston on front dead-center. Measure from dummy pin in link to eccentric crank pin and repeat for back dead-center. Move eccentric crank until both distances are the same and clamp eccentric crank. Then, make an adjustable eccentric crank rod.		# Use inside calipers. Set piston on front dead-center. Measure from dummy pin in link to eccentric crank pin and repeat for back dead-center. Move eccentric crank until both distances are the same and clamp eccentric crank. Then, make an adjustable eccentric crank rod.
	# Then to check length of eccentric rod, again set piston on front dead-center and move gear up and down. Valve should not move. The same for back dead-center.		# Then to check length of eccentric rod, again set piston on front [[Dead center\|dead-center]] and move gear up and down. Valve should not move. The same for back dead-center.
	# Then set valve to get equal leads, front and back, when radius rod is in mid gear (or in the center of the link).		# Then set valve to get equal leads, front and back, when radius rod is in mid gear (or in the center of the link).