Hydraulic Hose Sizing - Revision history

Tom Griffing: /* Supply (Pressure) Hose */

2017-10-19T10:02:39Z

Supply (Pressure) Hose

← Older revision		Revision as of 10:02, 19 October 2017
Line 207:		Line 207:
	\|(32.28 GPM / (3.117 * pi/4 * 20 ft/sec) ) ^ 1/2		\|(32.28 GPM / (3.117 * pi/4 * 20 ft/sec) ) ^ 1/2
	\|0.812 in		\|0.812 in
			\|-
			\|48 GPM
			\|(48 GPM / (3.117 * pi/4 * 15 ft/sec) ) ^ 1/2
			\|1.114 in
			\|(48 GPM / (3.117 * pi/4 * 20 ft/sec) ) ^ 1/2
			\|0.99 in
	\|}		\|}

Tom Griffing: /* Suction Hose */

2017-10-19T09:58:59Z

Suction Hose

← Older revision		Revision as of 09:58, 19 October 2017
Line 293:		Line 293:
	\|(32.28 GPM / (3.117 * pi/4 * 5 ft/sec) ) ^ 1/2		\|(32.28 GPM / (3.117 * pi/4 * 5 ft/sec) ) ^ 1/2
	\|1.62 in		\|1.62 in
			\|-
			\|48 GPM
			\|(48 GPM / (3.117 * pi/4 * 4 ft/sec) ) ^ 1/2
			\|2.21 in
			\|(48 GPM / (3.117 * pi/4 * 5 ft/sec) ) ^ 1/2
			\|1.98 in
	\|}		\|}

Tom Griffing: /* Return Hose */

2017-10-19T09:51:03Z

Return Hose

← Older revision		Revision as of 09:51, 19 October 2017
Line 247:		Line 247:
	\|(32.28 GPM / (3.117 * pi/4 * 15 ft/sec) ) ^ 1/2		\|(32.28 GPM / (3.117 * pi/4 * 15 ft/sec) ) ^ 1/2
	\|0.938 in		\|0.938 in
			\|-
			\|48 GPM
			\|(48 GPM / (3.117 * pi/4 * 10 ft/sec) ) ^ 1/2
			\|1.4 in
			\|(48 GPM / (3.117 * pi/4 * 15 ft/sec) ) ^ 1/2
			\|1.114 in
	\|}		\|}

Tom Griffing: /* Horsepower to Flow */

2016-10-03T11:58:55Z

Horsepower to Flow

← Older revision		Revision as of 11:58, 3 October 2016
Line 99:		Line 99:

	4.4 * 0.97 * 1800 / 231 = 33.2 GPM		4.4 * 0.97 * 1800 / 231 = 33.2 GPM

			Here is the case for a 7 HP engine running at 3600 RPM:

			7:(1.84 * 3600) = 51:(R * 3600)
			-or-
			R = 7 * 1.84 / 54 = 0.238 CIPR

	== Pump Sizing ==		== Pump Sizing ==

Tom Griffing: /* Horsepower to Flow */

2016-10-03T11:38:12Z

Horsepower to Flow

← Older revision		Revision as of 11:38, 3 October 2016
Line 27:		Line 27:
	\|2 GPM		\|2 GPM
	\|2 * 231 / (3600 * 0.97)		\|2 * 231 / (3600 * 0.97)
	\|0.~~064~~		\|0.132
	\|-		\|-
	\|28		\|28

Tom Griffing: /* Horsepower to Flow */

2016-10-03T11:36:17Z

Horsepower to Flow

← Older revision		Revision as of 11:36, 3 October 2016
Line 20:		Line 20:
	! Displacement Formula		! Displacement Formula
	! Displacement		! Displacement
			\|-
			\|7
			\|3600
			\|3000
			\|(7 * 1714) / (3000 * 2)
			\|2 GPM
			\|2 * 231 / (3600 * 0.97)
			\|0.064
	\|-		\|-
	\|28		\|28

Tom Griffing: /* Horsepower to Flow */

2013-08-17T01:48:30Z

Horsepower to Flow

← Older revision		Revision as of 01:48, 17 August 2013
Line 44:		Line 44:
	\|17.14 * 231 / (2700 * 0.97)		\|17.14 * 231 / (2700 * 0.97)
	\|1.13		\|1.13
			\|-
			\|65
			\|2700
			\|3000
			\|(65 * 1714) / (2500 * 2)
			\|18.57 GPM
			\|18.57 * 231 / (2700 * 0.97)
			\|1.637
	\|}		\|}

Line 63:		Line 71:

	2.5 * 0.97 * 2700 / 231 = 28.34		2.5 * 0.97 * 2700 / 231 = 28.34

			Here is the case for a 51 hp engine at 1800 RPM:

	54:(1.84 * 3600) = 51:(R * 1800)		54:(1.84 * 3600) = 51:(R * 1800)
Line 68:		Line 78:
	R = 60 * 1.84 * 3600 / (54 * 1800) = 4.008 CIPR		R = 60 * 1.84 * 3600 / (54 * 1800) = 4.008 CIPR

	So, this "rule of thumb" measurement puts the displacement at about 2.5 CIPR and 28.3 GPM flow:		So, this "rule of thumb" measurement puts the displacement at about 2.5 CIPR and 30.23 GPM flow:

			4 * 0.97 * 1800 / 231 = 30.23 GPM

			Finally, the case for a 65 hp engine at 1800 RPM (pulley reduced RPM from 2700 @ engine to 1800 @ pump):

			54:(1.84 * 3600) = 65:(R * 1800)
			-or-
			R = 65 * 1.84 * 3600 / (54 * 1800) = 4.43 CIPR

			So, this "rule of thumb" measurement puts the displacement at about 4.4 CIPR and 30.23 GPM flow:

	4 * 0.97 * 1800 / 231 = 30.23		4.4 * 0.97 * 1800 / 231 = 33.2 GPM

	== Pump Sizing ==		== Pump Sizing ==

Tom Griffing: /* Horsepower to Flow */

2013-07-10T23:02:10Z

Horsepower to Flow

← Older revision		Revision as of 23:02, 10 July 2013
Line 50:		Line 50:
	In the past, the preferred power for the LifeTrac has employed ~54 horsepower @ 3600 RPM to drive two pumps, each about 0.92 cu in displacement. This has proven satisfactory and is the rule against which the new Power Cube will be measured. The total pump displacement was 1.84 CIPR (Cubic Inches Per Revolution). This gives a ratio of HP:Flow of 54:(1.84 * 3600).		In the past, the preferred power for the LifeTrac has employed ~54 horsepower @ 3600 RPM to drive two pumps, each about 0.92 cu in displacement. This has proven satisfactory and is the rule against which the new Power Cube will be measured. The total pump displacement was 1.84 CIPR (Cubic Inches Per Revolution). This gives a ratio of HP:Flow of 54:(1.84 * 3600).

	For the new Power Cube, the engine will be producing between 50 and 60 hp @ 2700 RPM (the RPM yielding max torque). So, using the above ratio to derive the new displacement as follows for 50 and 60 HP:		For the new Power Cube, the engine will be producing between 50 and 60 hp @ 2700 RPM (the RPM yielding max torque). So, using the above ratio to derive the new displacement as follows for 50, 60 HP @ 2700 RPM and 51 HP @ 1800 RPM:

	54:(1.84 * 3600) = 50:(R * 2700)		54:(1.84 * 3600) = 50:(R * 2700)
Line 63:		Line 63:

	2.5 * 0.97 * 2700 / 231 = 28.34		2.5 * 0.97 * 2700 / 231 = 28.34

			54:(1.84 * 3600) = 51:(R * 1800)
			-or-
			R = 60 * 1.84 * 3600 / (54 * 1800) = 4.008 CIPR

			So, this "rule of thumb" measurement puts the displacement at about 2.5 CIPR and 28.3 GPM flow:

			4 * 0.97 * 1800 / 231 = 30.23

	== Pump Sizing ==		== Pump Sizing ==

Tom Griffing: /* Pump Sizing */

2013-05-29T21:50:11Z

Pump Sizing

← Older revision		Revision as of 21:50, 29 May 2013
Line 81:		Line 81:

	Source: [[http://www.loaderpartssource.com/bobcat-parts/bobcat-hydraulic-pumps?oem_model=392 LoaderPartsSource.com]]		Source: [[http://www.loaderpartssource.com/bobcat-parts/bobcat-hydraulic-pumps?oem_model=392 LoaderPartsSource.com]]

			James Slade and I have discussed this at some length and decided that we'd like to use pumps and hydraulic motors similar to those in other skid steer equipment - such as those listed above. We do need some details about each of the three pumps in the "triple pump":
			Max/Rated RPM
			Max/Rated PSI
			Rated GPM for each

			As well as the pump dimensions, weight and operating characteristics of the built-in pressure relief valve.

	It is not clear yet what the type of pumps used, but one article indicates that the tracks are driven by variable-displacement pumps and the arms & accessories driven by fixed-displacement pumps.		It is not clear yet what the type of pumps used, but one article indicates that the tracks are driven by variable-displacement pumps and the arms & accessories driven by fixed-displacement pumps.

Tom Griffing: /* Pump Sizing */

2013-05-27T02:00:22Z

Pump Sizing

← Older revision		Revision as of 02:00, 27 May 2013
Line 82:		Line 82:
	Source: [[http://www.loaderpartssource.com/bobcat-parts/bobcat-hydraulic-pumps?oem_model=392 LoaderPartsSource.com]]		Source: [[http://www.loaderpartssource.com/bobcat-parts/bobcat-hydraulic-pumps?oem_model=392 LoaderPartsSource.com]]

	Note: Using multiple pumps to drive isolated circuits would result in multiple separate circuits - each with smaller hose sizes and associated plumbing.		It is not clear yet what the type of pumps used, but one article indicates that the tracks are driven by variable-displacement pumps and the arms & accessories driven by fixed-displacement pumps.

			Note: Using multiple pumps to drive isolated circuits would result in multiple separate circuits - each with smaller hose sizes and associated plumbing. The suction plumbing could be aggregated to simplify the design to use a single suction strainer and hose. Similarly, the return plumbing could be aggregated to use a single oil cooler and return filter.

	== Hose Sizing ==		== Hose Sizing ==